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Airline Pilot Technical Theory, Aircraft Accidents Adam Howey Airline Pilot Technical Theory, Aircraft Accidents Adam Howey

Manuals

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00:00

Verbal Reasoning

Adam Sam. Manuals. Yeah, when did you last have a reading lesson? I was going to ask you. Whether you remember doing those verbal reasoning exercises, Obviously, and selection for airline, I don't know about you. But I kind of always wondered like what are these for it because And now you need maths to be a pilot and maybe, need physics and a bit of science.

00:22

But Why you need to be able to read a passage, that's really confusing and say if statements are true or false or cannot say and I never really understood it Until I, Start flying and reading manuals. It's this passage is this statement. Patently true. Yeah. Patiently untrue or cannot say yeah.

00:41

Well everybody knows because I'm a pilot that I'm really good at maths. why you laughing. Yeah. Okay. Yeah, I'm not so good at maths or physics. Really? No But I'm any good at verbal comprehension. I feel that That you would definitely better at verbal comprehension and I was used to carry me through verbal comprehension sort of practise.

01:04

That was selection test. Yeah. When we were prepping for selection, might my, my verbal reasoning was my weakest and it was the same through school at English language was was one of my weakest. Subjects, I struggled with it. And yeah, I couldn't really understand why it formed part of selection, but now I do, Well as I've got old, I think I've become more and more interested in other careers.

01:26

And and what they really mean when you're Like 16 or earlier. And yeah you think to be a pilot they must be really good at maths and physics. And you're understanding of what is involved in a career is made up of laser cliches. I don't think the career services that was available to me at the time.

01:44

Really helped me understand what a job really involved. For example. My understanding of a solicitor or a lawyer. Is that the main skill is the The use the ability to wield the English language. Yeah, they're advantage. Definitely. And that's kind of playing into what What we're going to talk about here, I think Yeah I think a lot of like law is is yeah, it's essentially just you're interpretation of The law and that's what solicitors and lawyers.

02:16

Argue over is what the meaning of that law is like, how that's written? How can that be interpreted? Is basically law, isn't it? But to how's that relevant to our topic. So it's relevant to our topic because these aircraft manuals, which will maybe go on to details and there is a lot of interpretation required and Will probably use this phrase a few times, but there's black and this white and there's grey.

02:40

Okay, so the manuals are written black and white. And something's a really clear in the manuals. You must not and it is forbidden or it's not authorised. Really clear but some stuff Can be a bit more grey, a bit more ambiguous and open to interpretation. You can use that to your advantage.

02:58

I'm or you can you can use that to help you. But, the important thing is is aircraft manuals are Big long. Lots of words and open to interpretation. So, I now understand why the verbal reasoning exercises were. Were part of selection. I, Don't have any physical aircraft manuals. No, when we started flying.

03:27

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Paper and Digital Manuals

Yeah, we were issued with Paper manuals. Yeah. So i remember like going to get mine in my first airline, it was like a whole day to go and collect your manuals drive, to the airport, and only had a small car at the time, but it was a good job.

03:41

I didn't have any passengers with me because it pretty much filled the whole back seats. It was a really effective, but up and down twice, I think it's like two boxes, massive boxes, full of. So, if that manuals issue to a pilot stacked on the floor, how high reckon Us like probably, like up to your waist at least.

03:59

Yeah, maybe more makes. You look really clever when they yeah, sat in your bedroom. Yeah. Of these with all these massive flight manuals. I used to get the updates, send in the post to meet you. So each little page is whole punched, and yeah, there's, I don't know what there, be like, 10 ring, binders, or yeah, yeah.

04:20

Provides to 10, ring binders. And then maybe more than five And then you were supposed to take each page that had any revision on. It could just be Could even just be like a ref like a, like a very small or something. Yeah. Yeah, the find that page. Rip it out.

04:37

Rip out the whole one. Put the new on him. Yeah. Which gave you? A. I have like flawless understanding almost of what had changed. Yeah. Because he had to physically . You had to physically insert it and the changes. Yeah, I agree. So if you got any manuals anymore, so no, it's all done on on.

04:55

Well, ipad or Android or you know whatever kind of tablet on a tablet basically. And yes, i don't have any manuals and you're absolutely right. It's hard to keep track of updates because you just tap a button now. And within 30 seconds or you manuals are updated and although it tells you, what the changes are you have to actually Actively interrogate.

05:17

You know, to make sure you understand the changes. So it's definitely harder, Perhaps, where we are now is like, It caught between. The the past where we had paper manuals and some point in the future, I can imagine Where, The information. Produce for pilots. Is. Is in its most usable dynamic.

05:43

Possible. And form. And why somewhere in the middle where we've got like digital versions of paper manuals. But they started to introduce like you've got your search functions you can annotate. You can Organise them as you like you can have multiple tabs open. Yeah. But In a sense that well, they are still digital versions of paper documents.

06:06

Yeah. Yeah. But a time may come, where the information that a pilot needs available to them, which is the manuals we're talking about, It might be organised completely differently. Yeah. Because it's Because, And the The options available digitally. Are like vast. Yeah, but having them organised in like, a sort of pseudo paper.

06:30

Like a fake paper document. Yeah or digital paper document doesn't necessarily suit the information. No yeah yeah. So I feel like we're sort of in the middle of Of that process. Obviously, the aircraft. We fly. You and I sorry and and say probably fifth more than 50% of the world's fleet was it.

06:50

They were all designed and built before. Anybody really foresaw. Tablets. Or Airbus have been committed to less paper cockpit since the 1990s. Yeah. So now we've kind of retro fitted tablets to most aircraft or airlines of retrofitted. EFB electronic flight bags by sticking. Laptops or iPads. Yeah literally like a sticking a game boy to the side of the flight there.

07:16

Yeah. To kind of try and integrate. And I'd actually like to talk about. The mix of this unregulated to to degree less regulated device. Yeah. It's stuck in such a regulated environment where all the other software we use and all the other buttons we press in the flight deck are so prescribed and well thought out and slow to iterate in.

07:40

Yet, you're sticking your iPad in which 10 minutes ago, you might have been Watching. Hey Duggeeon with your kids at breakfast then you open it up in the flight deck and it's still there. Yeah, it's like a it's like It's a crash in of like the future. Yeah and the wild west of technology right into the flight deck which should be the most stale sterile like objective focused environment like we used to bring a newspaper into the flight deck and that was the most foreign object in there.

08:08

Yeah. And now you potentially have Singing and dancing internet with Netflix. Yeah, right, right beside the side stick. Yeah, So that's something that's interesting to me. I'm on that topic. Why? One of the I always, you know, when we've issued with our tablets, I always thought like that'sn't you know, surely like it's just cheaper to keep paper manuals like like issue.

08:33

However, many hundreds or thousands, depends on the size of your airline that many iPads or tablets that must That must be a huge cost but then I because I like maths, I worked out Say I figured it out that based on about 20 kilogrammes of manuals. On an aeroplane, it would cost 800 grams of fuel per hour to carry those manuals.

08:54

So what account?. Yes, it basically, I went out that and an aircraft would have to fly for 200 days. To pay without manuals to pay for two iPads. For like the Captain And so basically. So it doesn't take long basically to cover the cost That's just the way of them.

09:11

That's just again, the processing and you had your, do you got their cost of print in the manuals in and keeping them updated at home? But the manuals has to be a copy of those manuals on board, the aircraft. Yeah. And When you park the aircraft up at night, if you're on the late flight.

09:27

Yeah. It's usually a guy with a van, you pulls up, and he used to be a guy, the van, he still comes up. Maybe with. We have a couple of manual sets still paper on the flight date but you used to come up and his job was to refill all the manual do that.

09:42

Same job that you do at home with the updates. Yeah and they're like a third party service usually. And now that third party service is some geek who who controls their dissemination of all these updates and stuff just via push of a button. Yeah. So it's obviously I mean it's yeah massive saving although Hard to like justify like buying hundreds of iPads, but easy cell to the pilot, so, isn't it?

10:04

Yeah, yeah. Here's an iPad versus like here's something you don't want to carry around in your bag like, yeah, definitely. Everybody's like, yeah, sure. Give it me. Yeah. Say. Do you want to talk about manual structure or more? Just I think. Very brief. Well, in your stride lighter talked to you as a trainer right now and ask you How much training of a new pilot.

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How to Use

10:31

And is geared towards the The use of the manual, the way to read it, the understanding of how it's organised. Um, very little really i suppose, I mean, certainly not very much when actively Training like a type rating but I imagine in ground school is obviously going to be one of the topics covered in ground school.

10:51

But during your conversion course, or your training, I guess reference might be made to FCOMs. Pilot operating handbooks training, manuals, that sort of thing point people in the direction of what about best practise. In what sense? Well, If you look at from a CRM point of view, Yeah, and the SHEL model which is taught to understand the environment you're in, you've got your software hardware environment, liveware, And software actually is the manuals and the procedures.

11:26

And Not necessarily the physical manuals. But, any written documentation that you might interact with The hardware would be the Include the software in the FMS. When we talk about software in the SHELL model, that's a whole part of that model because the the manuals, the operating procedures, makeup such a big influence.

11:47

However, If they're a system in their own right? Yeah. How much training do we have on? Oh yeah. I use of them. Yeah. And how they're designed and their flaws and their good things that are very little really like very little in my opinion it's more you might Come up with a situation in training where you need to refer to?

12:08

Yeah, a manual. But so just you know by default you end up talking about manuals but I think there's no. I wonder how often a pilot is interrogated like in the in-training or examination as to how they actually understand the information that they're using and and where they got it from, yeah, often now.

12:26

A pilot will Google inverted commas. Use the search function in the digital manuals to find the keywords and find information. Yeah. Some maybe like quite rigorous about the hierarchy of that information. Like where it which manual it sits in? Yeah. In what context? Others might just read the sentence.

12:46

Yeah. And then go I can use that sentence to prove or disprove what the information I need. Yeah that's it's just interesting to me if If we do need or don't need training on the use of the manual. So your question was, do we talk about how they're organised in my opinion?

13:05

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What is Included

The organisation of the manuals is really important to understand. So we've been using the word manuals but you just said FCOM flight crew operating manual. Yeah some places in the world might refer to is the flight manual or the aircraft flight manual or just a pilots manual. Yeah. But we're talking about information.

13:25

That is specifically given to the pilots. Yes, in manual. Format. Yep. And these manuals have to serve you. When you're training. From being a new pilot when you're doing a type conversion, when you're on the line, they have to serve training captains. You know examination, pilots everybody uses the same document So that document Has to be written with the with the user in mind and the use cases in mind.

13:52

Yes. So it's really interesting to me how it's written what information is included to the pilot and what isn't because if you're in a learning, Process. So you'll learn to be a pilot that is somewhat of a linear process like as you learn bit by bit, but we use these manuals.

14:10

It in addition to like, when we're learning to fly the aircraft, we use them right in the middle of the line operation. Yep. So it might be that I need to look up how to fly a non-precision approach. So the way that it's written and the system of information that's presented to me there, It's like being carefully thought out.

14:26

It's like what does this pilot need to know right now. Yes and what don't they need to know and how do they need to know it? And and then you go through your whole career. So sort of Understanding the aircraft and the procedures that you fly through the lens of.

14:43

Somebody who's decided what what you need to know and what you don't need to know. That's very true. I mean, On a normal flight. I mean, how many times would you look at your manuals? Probably At least. 10. 20, maybe. Yeah. We use them all the time. Basically. Yeah, we do.

15:03

I mean, you've got pilots who He won to know, want you to know. That they know more than you about something and they'll have information. That's not in any of their manuals. Yeah, you might even have trainers who Make a point. I mean, when I was a technical instructor, The line you are treading was if you had the luxury of a day to train a pilot about the fuel system.

15:27

They they would they would a lot of them would really enjoy. Find out things that they hadn't known for 10 years or something about the fuel system, but how relevant Or dangerous. Is it for them to understand that piece of information? Yeah. And what purpose are we serving? You know, by Of having people or documents that like, give you that extra information.

15:49

Yeah. Part of the digital manual. Now is that you've got your level one two and three I don't know if how common that is with. Digital documentation. In other airlines. But the service that we're familiar with you've got like level 1 which is like need to know. Yeah, you can press a button and then Instantly are underneath the information.

16:08

If there is any level two information it will appear. Yeah when it wasn't there before and that's like a nice to know. Yeah. And then you've even got level three. Yeah which is like training. Captain Trivia. Yeah. Well yeah we theorists like yeah. Help understand. Yeah. Yeah. Agree. Talking about manuals just to get to the core of it.

16:29

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Why have a Manual

It's important. It sounds boring. But in your career, this is like the main way that I mean, what is an airline, you know, when you take away all the pilots and the CEOs, what would be left? It would be the manuals. Like, what is different about one from one.

16:44

Airline to the other, that's actually tangible. Which it should be written in the manuals. Yeah. And the aircraft manufacturer, they write all the manuals that you need. Yeah. And then an airline comes along, guys. Well, we know better. So we're gonna rewrite the the SOPs, which much frustrate the manufacturers.

17:01

Yeah. And they have to, I think sort of approve the variations of the way you operate the aircraft and as the world's become a bit more litigious. The airlines have realised, they need to go back to and sticking more closely to the way the manufacturer say you fly the aircraft.

17:17

Yes, there's a crash. Yeah, the court say, hold on the people that design, the aircraft said, flight like this and you've come along said flight totally differently. Yeah. Yeah, it's interesting, isn't it because obviously, The airlines have to adapt it slightly to their own operations. Every airlines operation is different and But you could argue but why I mean yeah, craft can operate I guess any other way as well?

17:38

That Changes are made is due to experience. I think that happens possibly, you know, incidents accidents. If there's been something happened within an airline or they've noticed a trend that we're getting into other things now, like, like monitoring of flight data and stuff, but if they notice any trends or things that happening then they might need to change the SOP.

17:58

Yeah, well, safety reasons, this comes down to what I'm saying, is what we actually talking about here. We talking about boring manuals, or we talk about, why they exist in the first place. Because I wondered, I wonder when the first aircraft manual ever came about. And I thought, well, in like World War II.

18:12

Yeah, they might not really have had much time to like, write a manual that and They might have decided, well, we are trained in a lot of pilots because we're losing a lot. So, We need to write something down because all the experiences being shot out of the sky and killed.

18:26

Yeah, it's like tangent. Yeah, I remember reading a book by Jeffrey Wellam who was Spitfire pilot and yeah I was like fascinated by the fact that he got pulled out of like he's equivalent of flight training early and after like a few hours of training in another aircraft just got thrown into Spitfire There.

18:45

Wasn't that there was no two seater is spitfire, there's no manual just like off. You gauge just getting figure out. Basically, there was no yeah, there was no manual, Ernest K Gann said the rulebooks are paper and they will not cushion a certain meeting of stone and metal. Yeah, but there's another clever phrase which is SOPs are written in blood.

19:07

So why have a manual at all? Well, every pilot that's gone before you who's made a mistake or nearly made a mistake as essentially written down or don't do this or do it like this. Yeah, and over years of aviation and what some people would even call Airmanship, on top of the manufacturers, understanding of what they've built.

19:28

You get these. Manuals, and at the core you get there standard operating procedures and you go outside them or you disregard them. At your peril. Yep. There's plenty of times. Where Ernest K Gann says the end of the day. The rule books not going to save is not going to be the last line of defence.

19:46

Yeah, that's the pilot's job. And the cabin crew are the goalkeepers, of the whole industry. Yeah. If anybody else can make a mistake, the manufacturer traffic control, the engineer in the morning, including the people that have written. The manuals can make a mistake. Yep. But if you stay with inside your standard operating procedures, Which are communicated on paper in manuals, then you're within a really well.

20:10

A risk assessed framework safety bubble? Yeah, of hundred years of aviation. Yeah. And however, many hundreds of that, millions of hours on their type that you're on. Yeah, So the SOPs and the manuals are updated to take account of current accidents best practises and Stuff reflecting in the whole industry.

20:32

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MEL

And a lot of that stuff. And, A big chunk of that operational stuff is in OMB. In the operational part. What's your favourite manual? I do like the FCTM Flight crew, the training manual. But that's because I've become, you know, I've used it a lot. I like the MEL MInimum Equipment List , what’s the MEL

20:55

The minimum equipment list? Yeah. MEL is basically so it forms part of OMB. And it's basically aircraft got like hundreds of thousands of parts moving parts. So this there's the minimum equipment list and the CDL, the configuration deviation list and I'll talk about briefly the differences. But yeah. So essentially The MEL out.

21:14

Tells you what bits of the aircraft can be missing, and it still be legal to go. And fly that aeroplane? So, How often would we open that book then probably figuratively, Probably. Like, Every other flight. I imagine so some flights you'll arrive for work and they'll be an MEL item.

21:37

So something, missing or broken or needs replacing And it'll give you a reference to the MEL. So you're going to look at up and make sure it's okay, it's in compliance. Or occasionally you might have a fully serviceable aircraft. But at some point during your day, Something goes wrong, or there's a failure of some sort of equipment, and you might refer the MEL To think about future implications.

21:59

Like if we go if we continue to destination, are we going to be able to depart back without this piece of? So we don't actually fly along with the manual on our lap. Like what do we do next? What do you? Yeah. And if something goes wrong. It's something breaks.

22:14

We deal with it in real time. Yeah. A modern aircraft using an electronic systems. It's a Push this button, turn it off. Turn this other system on And what you're saying is that A the consultation of some manuals like the MEL is basically done on the ground so we carry them with us and then we think a for the next sector And watch the implication.

22:36

You know, something going wrong. Can we plan a fly with something? This, there's not working. So an example might be something as serious as you might have two systems on an aircraft that pressurise, the aircraft and one of them might not be working, but we can still go fly in but it might say well the speed breaks have to be operative.

22:57

Because if the pressurization system fails, you would need to descend a certain rate to ensure the cabin attitude stayed breathable, and you need the speed breaks to do that. So if the speed breaks happened, not to be working as well. Yeah. Just by coincidence. Then you can't carry this defect But then we started off by talking about verbal comprehension.

23:19

Yeah. So, You might be opening this manual. You've not got long before you supposed to depart. You have to read this text declare that people say about the Airbus. For example, it was written by Manufactured by the French written by a German translated into another language and then into English or something.

23:37

Yeah, yeah. So you've got a read this manual. Got to comprehend what it's saying. Yes. And sometimes you want the manual to say something, then. And you're able to interpret it in a certain way. Certain way. Yeah. But if there's any doubt there is no doubt, no, you can kind of bend the manual.

23:54

In certain directions and navigate the grey which is what you're saying earlier. Definitely. Yeah. You don't have to be. Yeah. Because the manual isn't the last line of fence. The pilot is yes to your interpretation of that manual. Can come in useful. It can mean it can. Well, In OMA is probably a line that says of, Captain's not happy then we're not going flying.

24:15

Yeah, yeah, yeah. Says, well, the MEL is a good example. Yeah, it will say the interoperability of defective systems is not taking account. So if the captain thinks well, the air leads US. Yeah, the APUs US. Yeah, and I'm doing a flight with the gear down and something the MEL hasn't taken account of all four of those to.

24:37

Yeah and he's just not a good day. Yeah, I don't know. Anyone explain it anymore, I'm not getting flying. Yeah, the MEL says exactly that, you know, in in isolation each of those, each of those items is means. You could go flying but all four together. Could put it into the unsafe or unacceptable, yes.

24:54

So yeah. Interpretation and sort is required The wording as well. you touched on the language? But yeah. The the amount of times you read in a manual, the difference between should and must It should is not recommended. It's required. It's Recommend it all this different. I think a good 15 years ago, the CAA went through all the And what was called, jar Ops, manuals and deleted “should”, and “could” which it was riddled with, yeah, because What does should mean?

25:30

Yeah, What does could mean? And I use that in my day-to-day life all the time after I'd learnt that Now, I don't think you should operate with. I feel that some people operate all the time in the back of their mind thinking that they're going to be stood in a courtroom, which It's never really occurred to me.

25:47

I don't know where some pilots. Where? I don't know where that, as strong feeling is that is, as come from, I don't. Fear the litigation. It doesn't hang in my head. I'm all the time. But I feel like some pilots do fly like they're gonna get in trouble all the time.

26:04

Yeah. And so should incurred. A meaningless. Yeah. So there are there are things that are Shouldn't could nest on necessarily meaningless no but then not very useful to a pilot but I'm trying to think of stuff. My yeah, yeah there's a lot of phrases in the manuals which are open to interpretation that are a bit useless.

26:26

So I one one, I read the day. Every attempt should be made too. But does that mean? I mean like, let me guess that's not in OMB. I can't remember where it was being like OMA. Yeah. Every attempt should be made too. So that's like well. This should be done, but if you've tried and you how many attempts then, how many?

26:47

Yeah, then maybe you don't have to do it, you know, it's like, and that's goes all the way back to this verbal reasoning. Kind of like, your interpretation of, yeah, those verbal reasons are made more sense. If they gave you an actual passage, From OMB that said, yeah, if no ILS is available then.

27:05

He should seek the approach with the lowest minimal or, you know, I give you no example in the performance manual, when it talks about runway, surface condition, for takeoff and icing conditions. There's a where it is really bad. It says do not take off. Yeah, but if it's quite bad, it says take off is not recommended.

27:23

Yeah. Okay. I probably wouldn't. But I could, you know, because it's not telling me a kind, it's just telling me it's not recommended. Well, Hi. You know, I might recommend that it is, you know, I mean, yes, that there is, yeah, I think that's, that's trying to, that's like, saying what I was trying to get out which is That could enable the flight crew to choose an option.

27:44

That they desperately seeking to be available to them. Yeah. But it would also give them the option to Risk assess. Like that. This is not. Yeah, this is not. Yeah, not recommended. Yeah, you don't have to do something just because the manual says you can do it. Yeah, exactly.

27:59

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SOPs

It's not. It's sometimes, I'm gonna. Yeah, yeah, I agree. So We talked about FCOM A,B,C,D, the MEL, what so what about SOPs was in, like, what are they and what, you know, gotta be the most well read. Part of all those manuals by a pilot. Yeah, it's incredible. Really SOPs.

28:17

I think, especially when I talk to people outside of Aviation And I say, they say to me, are you going flying today? Yeah. He, you know, you flying with. No, no never met them before. What's you're going to go? Meet somebody and then just go fly, an aeroplane with them.

28:31

Like yeah. How do you do that? Well, what we have SOPs standard operating procedures. And yeah, i mean it is amazing, really, if you take yourself out side of aviation and think That you could literally turn up at work. Meet someone, for the very first time, you don't know anything about them.

28:49

But an hour later your your flying an aeroplane with them. It's like, An actor from a musical. On one side of the world. Standing in for somebody. On what's the one in New York called? What Broadway? Brought an actor from music on Broadway? Who's never met the guy in the West End, He standing in.

29:10

With no rehearsal whatsoever. Yeah, and they have to dance And together for two hours. Yeah. And sing together for two hours. And yet there's flawless. Yeah, yeah, every light no line is missed. No beat no, no step in the dance is missed at all because the SOPs are so well rehearsed.

29:30

Yeah, yeah. And I do think it's a part of our manual. That is very well written and probably less Less ambiguous in the SOPs. I don't think there's many SOPs, that are open to interpretation and like, Maybe statements in OMA, or you get these things on the line, where one pilots, And you and that their few and far between where, where half the fleet of pilots interpret.

29:53

Its one way and the other half the other way. Yeah. And it becomes like a little comedy or wonder which way they're going to say that line or something. Yeah. It but usually if that's something rears it head like that, then training managers are generally quite quickly quickly to quash it in some sort of publication of Either a safety, you know, a safety report or a notice or because if it doesn't if it doesn't become dealt with yeah or worse.

30:19

If there's something that isn't that, it's that the entire fleet interprets. Let's call it the wrong way. Yeah, to how it was intended. They're not following the SOP basically. And it becomes what? Some cool like, a normalisation of deviance . Yeah, which is So, a lot of accidents you're looking at, And although the manual said to do it this way, everybody just did it this other way.

30:46

Yeah. And that was one of the layers of the Swiss cheese that cause the accident. Yeah. And it's so normal to do it the wrong way. Yeah, that You don't even know that you're doing it the wrong way. No. I'm trying to think on the an old fleet on the 757, the recirculation fans that call the You know, avion exercising was, so noisey.

31:08

The on turnaround, Everyone would just reach up and turn them off in them off. There's no way that's allowed under any of the manuals was however, and who knows what kind of, you know, accidents that could allow a path towards. Yeah. And that's just a minor example. But it was so normal.

31:23

You know how I feel about speeding and on roads? Yeah, the rule is you don't exceed the speed limit. Yeah, I don't know. 999 out of a thousand people. Wouldn't lose an ounce of sleep over the fact that they sped 40 in a 30 or something, the day before, even police officers and so on.

31:41

Yeah, because to me that's like a normalisation of something, that's different, that's different. Maybe a whole Podcast episode could be on SOPs. And yeah. It's probably use and theory of them. Yeah. You talking about their well-written. Not open to interpretation. It. Today I'll include things like The calls. To the letter that you say yeah.

32:03

In the flight deck to the point where Boeing say that the word check. Is American. So, Have we got the fuel on board “check” means, yes, yeah, but in European manual, check means you need to check that and checked means it was checked, you know, so they can be that specific and they include the things.

32:26

You say the buttons, you press the order, you do it in basically chronologically as you progress through the flight, but we don't see there with the manual open. No. We just know them inclusively. Yeah. That's one of the things that you there's drawn into your Training that you have to learn the SOPs.

32:41

Absolutely 100%. Here, you can't be. Referring to them in the middle of not be referring to the SOP on how to fly a non-precision approach. While she flying an non precision approach in. Yeah, you need to know it really And then if you have a big SOP change, It's really annoying and stressful.

32:58

Yeah. Yeah. Because it's sick because the brain. Wants to follow the path of least resistance and so it knows. Every little muscle in the mouth. How to say the checklist? Yeah. Be must never do the checklist from memory. Your brain is begging you to. Please do it for a memory so I don't have to pick up the checklist.

33:17

It's like save every little Calorie. Yep. And every SOP is Is like efficient to to a pilot because they know them inside out, they don't have to think. About the SOP and then when they're suddenly changed everyone needs to think. Yeah. And that's annoying. Yeah. Uses precious energy that was become like a muscle memory, like the SOP?

33:38

Yeah. Other things to talk about which was it was only really I took about this is it was an example of what comes at the day and We've talked about discrepancies and things open to interpretation. But there are Engineers. He look after our plane, they've got a different set of manuals and generally, they all marry up, but there's sometimes there are like huge.

33:59

Discrepancies and the engineer is manuals says, completely different to what our manual. So the example of the day there was It doesn't MEL item for one of the those bit fluctuating in one of the outer tanks to fuel. So the MEL says that after every refuelled either the tanks need to be dipped by an engineer to check the fuel on board.

34:22

Oh, you have to go and read the gauges from the refuelling panel on the belly of the aircraft. That's what the MEL said, either raw. That an engineer arrived is like, hey guys, I've come to dip the fuel tanks. All right, it's okay. We don't we don't need you.

34:34

We don't it this way and he was like, no, you can't do it that way. The engineering manual says, it has to be tanks dipped. All right, so there is errors in manuals and discrepancies and Engineers have manuals cabin cooperating manuals. There's always going to be It's like differences.

34:53

I just throw that in there as an example of But then, if you've looked at any accidents, Um, but the, the all the ones I wanted to use is example, was where the engineers had made mistakes interpreting the manuals. You're not where pilots had. Yeah, I think was really fair.

35:09

No, and for the spirit of this, but Very recently. There was an A321, at Gatwick. Which almost had a double engine failure, right? A Titan airways. Okay. I don't know about this, but it was a mistaken engineer had made by using, like a thousand times too much. Of a bioside which cleans out the fuel tanks then they should have, Wow.

35:31

Due to Less than rigorous use of the maintenance manual, and some assumptions made and some interpretation errors . You know, like spacecraft that have crashed because one person was in metres and one was in feet or something like that. You know, something along those lines and I found plenty of those.

35:48

I mean, remember Gatwick again, and you remember the pilot that got sucked half sucked out of the window? Yeah, the engineered replace the window with the wrong bolts on bolts. Yeah, mind you identify. That was An interpretationary on the manual, but all the ones it came to me were maintenance.

36:04

Reading the maintenance manual. Yeah, in error. Yeah. And In my old airline, we used to have the maintenance manual. So, i don't want to get to boring, but you'd have a defect, and you'd be like, right? Okay. So can we get back to the UK? So you're looking at your MEL, Yes, you can but there's a maintenance procedure that it must be done by an engineer basically.

36:25

So What is it? So, we would be able to see what they have to do. I don't understand necessarily, but I can understand generically what what's involved Might you know involve something significant or you know you can now we don't have that access that manual anymore So I don't know.

36:44

I can't think ahead about what they're maintenance has required to take. So that part of the need to know, nice to know. Yeah. Or potentially dangerous to know you because, you know, it might say, just going clean the sensor and you know, I can do that. I could do that or you might see an engineer doing it and then in a couple years time, you get the same 14.

37:03

You I've seen this done before, I've seen. Yeah, in fact in my previous airline we were training pilots to do two or three, basic engineering things, One of them was bird strike inspection. Okay, one was CB Reset. Okay. And there was another one. Yeah, because there's not always an engineer where you go in.

37:22

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The Manuals Sat Next To You

Yeah. We've kind of covered, broadly, the layout and Fact that there's a lot of information, it has to be interpreted, you have to know your SOPs. I think you're right. A whole, an episode and SOPs would be Would be useful. Anything anything else? Any other topics? You think we should be covering a manuals.

37:44

I think, I just want to get across to If it was ATPL student, just what the manuals, come to mean to you in your career, which is sometimes you'll feel like The captain is wrong. Sometimes you might even feel like the training captain is wrong. And they may or may not be more into understand furthery moment.

38:03

A question people, sometimes you might feel like you whole airline or your whole Aviation Authorities. Got it wrong. Yeah. And the manually is What you can sleep at night with if you want as like a young pilot, you know, you can really get to know the manual and often you will understand the manual inside out and the line captain that you're with won't And have kept up to date with it like they might of and but they will have the context to add to it.

38:30

And so these manuals and your relationship with them over the years, is kind of interesting. And if you're young and enthusiastic like it's really, you're only source of like go to What will you read the manual? Again, is because you as a new pilot, you haven't got the experience.

38:44

So them, so you've got, but you've got the knowledge or access to the knowledge. So, whereas a someone who's been flying for 20 years, it's got loads of experience. And it's probably less reliant on the manuals because they've I think, yeah, that's all you got to go to as a new pilot is the manuals because you haven't seen it before, you haven't got the experience.

39:02

So The manual is a tool just like lots of other things that you're use as a pilot. Like humans the manuals can be flawed. Yeah. So I'd say to any Any new pilot that. Embrace like any enthusiasm. You've got by reading the manuals but the greatest manual that you've got is the one set next year on the flight deck.

39:22

Yeah. And if you can, Keep up your Enthusiasm. Use that experience that sat next year as like a manual that you can flick through. Yeah. And talk to you about your understanding, the operation in conjunction with year, interpretation of the written text. Yep. Then you'll be working as a professional.

39:40

Yeah. Sounds good. All right. Okay, Cheers. Bye.

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Airline Pilot Technical Theory Adam Howey Airline Pilot Technical Theory Adam Howey

TCAS

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What Is TCAS

Sam. Adam. TCAS. Yeah, traffic collision. No. Traffic alerting. Traffic alert and collision avoidance system. Yeah, that's it. Which is a type of ACAS, Airborne collision avoidance system. That's the only one really until maybe some time in the future, which we might talk about. How recently have you had a TCAS RA?

00:29

Resolution Advisory I have had one or two. Where was it? Obviously flying into Amsterdam. And it was a surprise, you not really, because we could almost see the traffic coming and it look very close to us and it wasn't actually An aggressive RA.

00:47

It was actually what was the command the command was monitor, vertical speed. So basically just to fly level, right? Destruction was to carry on flying level, where we were Yeah, so it was pretty young eventful, but we obviously went through the whole process of save the day, did it?

01:01

Yeah, this guy went underneath this about 400 feet. Wow. I could say I'm all the way it was a king. Was like a king air. Okay, but, yeah, just going down the beach. We were on approaching to AMS Amsterdam. What did the Dutch have to say about that? They weren’t very interested really.

01:15

I told him that we had a TCAS RA. Told him that it was because he could hear the guy on frequency. Let's say just like yeah, we'll put in a report , rewind then TCA. Yeah, what is it? Traffic. No. But what is it? Oh, what is that? Sorry. So well, what's it done for you?

01:35

So it's It's an avoidance system built into the aircrafts transponder. Of all aircraft with mode. Charlie, with altitude information can have TCAS, and TCAS to talk to each other. So, That they can issue instructions between aircraft. They can interrogate each other and talk to each other and provide avoiding action.

02:00

To prevent to prevent a midair collision basically? Yeah, it's a tool for preventing mid-air. Mid air collision . So like, mid air collision loss of separation. One of the biggest. Categories of aircraft accidents. Yep. I think TCAS has done a good job of Definitely keep an accident rates in that category way down. Yeah.

02:23

So I think TCAS was made mandatory in about 2000s. I think in European airspace and apart from the one accident which we're going to talk about, what could that be? So, that would be the mid air collision over the German Swiss border Uberlingen, okay? Part from that one. I can't really think of any other.

02:45

Mid-air collisions. Between between aircraft that have been equipped with TCAS. Yeah. Okay. So surprises me that it was only mandated after the 2000s. Yeah, I think it was 2000. It was mandated. Yeah, pretty successful system. You like it? Yeah, yeah, I do. Yeah, I love it. It's pretty simple.

03:07

Yeah, and it's only there as a backup. If a mistake by pilot or air traffic control, Yeah it's labelled as a safety net. So yeah GPWS Ground Proximately warning system being another one TCAS. A safety, net being almost as if all other Possibilities to catch that accident have failed.

03:27

And this is the last thing that's going to Save you apart from the pilot being the The inbuilt traffic collision avoidance system if you like. We can always prevent an accident but TCAS is a safety net. There, You've told me it's to stop as hitting another aircraft from what airborne?

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03:42

What does TCAS do

Yeah. So practically What does it look like to you when you had your TCAS? So it built up our situational awareness as well, even without issuing warnings or advisories because it displays other aircraft on our navigation display. In form of a little diamond. So you can look at your map.

04:00

See other aircraft that are that are equipped with TCAS. And you can see where they are in relationship to you and what altitude above or below. So, what use is that and Well, it's good for your own awareness. Particularly in like a busy TMA around an airfield, you can Building up your situation awareness as to where you might be in the sequence for approach, where are the traffic is?

04:25

If you're maybe requesting further climber a traffic aren't giving it to you, you can maybe see the reason why because there's traffic above you, that's about to cross. So front of you, So actively we're actually using it most of the time. Yeah. For not what it was designed for.

04:40

Yeah. Exactly. I mean it is designed to raise your SA but you're looking okay. The person in fronts two and a half miles in front of me on the approach. If you get any closer that's going to be a go around close, you're saying I want to climb out this table in this but I can't because somebody's I can see somebody 2000 feet above me.

04:56

That's going to cross in front of us in the next two or three minutes. So it's like on our ND moving map kind of crudely. We almost have like the air traffic control is radar. Yeah exactly. Yeah. Except that it's not as cluttered because it only gives us certain aircraft depending on how we've got it set and Yeah.

05:16

What we thinks relevant to us. Okay, so what when we get more involved in it, what happens next? Then I suppose so it goes from a hollow sort of white diamond. The next sort of phase if you like if you're getting quite close to another potential conflict or potentially intruder, The the diamond gets coloured in.

05:35

So it's now like a solid white. That diamond and that is It's essentially potentially intruder. This that see that yeah, coming quite close to us in terms of literally, or vertically or their rate, whatever rate their climbing or descending out, or your climate, go to sending out is a potential.

05:54

Conflicts make quite proximate traffic. That's right. Yeah. So that would, that definitely draws your attention to the navigation display. I find if you see one, you see, one go coloured in. What would you do then? Okay, you can see proximate traffic. Yes. So again great tool for situational awareness.

06:13

That makes you think, right? That somebody close to us approximate traffic. So I might adjust my rate of climb my rate of descent. If it's particularly excessive, I might look at the window. To see if I can see them. So again, yeah, probably share your mental model with your.

06:29

Yeah, exactly. Say, have you seen that? I've seen that look. We've got traffic there. Even ATC, sometimes might point out that there's traffic. And your traffic in your one o'clock while thousand feet above. So it's raising or you giving your opportunity to raise your SA. Maybe think ahead about what might be next.

06:49

Possibly silently review the TCAS manoeuvre. Should it happen, Okay, so what what would happen next? So the next level would be a traffic advisory at TA and in this case, the little white diamond would turn to a orange diamond and then the system the TCAS system would then call out to you.

07:10

That i'm not going to do the impression. You have to “traffic traffic”. That's really good. Thank you, sort of an American accent. Traffic traffic, that definitely gets you attention. Yeah. So that would if not already that would draw both pilots, every airline will have different operating procedures but There will be possibly, some sort of call then between the pilots as to Who is at least in control of the aircraft or Some sort of separate procedure to almost get them ready for what may come next.

07:40

Should you manoeuvre? Now based on that? No, Well, I mean every airline might be different but I think Some airlines you might be told to maybe adjust your rates, but Other airlines will say no just Really don't don't interfere. Basically, just leave or preparing and just prepare for what may or may not.

08:01

Come next, Somebody looking for the traffic. Yeah, so one generally, one pilot will start looking out for the traffic whilst the other. There is looking in on the navigation displaying and getting ready for the manoeuvre. You know, what's next? So then the final level, which if it gets to that it is resolutionary advisory.

08:19

So, resolution advisory RA. So That's when I think the diamond goes to a square. I think you're right. Red square. Right. This all being an airbus, this is all air bus. Yeah. Obviously. And then you'll get some instruction basically from TCAS and the TCAS will actually tell you What to do and as a could be a simple as Climb.

08:40

Climb this and descends. Monitor vertical speed adjust vertical speed. Increased climb. Decrease climb. Few others as well probably. But the systems are we talking to each other? So the other aircraft may or may not get an instruction Sometimes. One, aircraft can get an RA, was the other record of trying to gets a TA.

08:58

All right, all right. So, Just stop us. Hitting another aircraft? Yep. It's a safety. Net should be the last thing. Really that saves us. That's what it looks like to a pilot. I'd say it's pretty simple works really well. It's very simple system and it does work very well and we practice it a lot in the simulator Probably over practiced it really for the actual amount that we not over practice it but we do it a lot considering.

09:22

Well, yeah, how you've had one in one and 13 years. Yeah, for two maybe things might have been tea, definitely had one into pafos. Because, airspace basis. Don't talk to each other there and people are trying to use high rates of climb to reach there. Cruise level. So, If we have an RA in the Airbus and it's pretty similar and all fleet, it's just like a really simple memory item for us to do.

09:46

Yeah, remember . What the memory item is the actions. So the actions would be to disconnect the autopilot. I'm turning off the flight directors. I'm so two reasons for that on the Airbus. Of obviously because you don't you not going to be following the flight direct just anymore. You can be following the TCAS instruction but also it reverts the thrust mode to speed mode on.

10:07

Yeah, on an airbus. So autopilot off flight, directly soft. And then following the TCAS into the green band, which is The TCAS kind of takes over your VSI, your vertical speed indicator. I know have big chunk of red and a little chunk of green. And it wants you to basically aim for the green.

10:24

So whether that's climb descent or maintain, and you should manoeuvre the aircraft into the green band. Of the way I train it is. And smoothly. But promptly so it's not it's not like a It's not yanking her But how simple is that? So green. Good, red bad. Yeah, exactly.

10:44

Definitely all pilot. Yeah, should be pretty simple for a pilot degree. Keep the authorised in. Yeah, and just just do it and just following, it didn't worry about anything else. Yeah, exactly. So it's Really simple in a really good way, really effective system. Yeah, I'm really happy with it as a system.

11:04

It's not even something that I'm sort of scared of. I don't like a GPWS but TCAS any day. Yeah, definitely that makes sense. And I think Taken into another level talking about, you know, passages on board in the commercial environment. I imagine if you had a TCSRA It's not that violence and manoeuvre.

11:24

I don't think mostly Some people have mentioned seatbelt. So it's not part of manoeuvre and I don't think they really need to know. So, is there any horizontal? Thing you need to do. In terms of well, the whole system is vertically based, which is genius. Yeah, it doesn't require you to turn left or right.

11:43

And if you're in a turn in the question is, what do you do? It? Don't matter. Yeah, he's just got a resolve, it vertically This genius and smoothly and promptly just inside the green band. If you even at high altitudes especially on a fly by wire aircraft. If you kind of Blip the side stick, you're going to end up in that green band quite quickly and smoothly, really Know.

12:04

is genius and am I right in thinking, you have four seconds to react. It might be, I think it's four seconds to react to an initial RA. Yeah, which is quite a long time, really. And if We'll talk about this maybe in a minute, a reversion. You have two seconds to react.

12:22

Yeah. Yeah. That's right. So I supposed to talk about now. So, reversion would be If either one aircraft, maybe wasn't. Following the TCAS or possibly you are Your climb climb, takes you into the path. Another aircraft. The different aircraft going above. You might get a reversion which then says, descend descend.

12:42

So you might actually swap completely what you're doing. And the green band has gone from right at the top of the VSI, your climbing to write the bottom. He has to be a bit quicker on reacting to a reversion because things are I forget the, the makes us sound pretty cool.

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12:57

Why TCAS, History

If anybody got four seconds to react but, you know, being possible not to do it really. It. So, As air traffic increased, call it in the 50s. But it was very famous mid-air collision over the Grand Canyon Which is when the FAA decided that they needed something to prevent mid-air collisions, okay?

13:16

But obviously, if you were going to increase air traffic volume significantly and mid-air collisions of factor, it has to be reduced to like near zero because The physics of the situation mean that any mid-air collision is basically always going to be catastrophic. Though, you know, in America they have a lot of mixing of like general and airliner aircraft as well into all sorts of airfields, which is like less.

13:40

I'm always surprised when I go to America, you know. Yeah. But although in Amsterdam You get our light aircraft. Yeah. Scoot and underneath you. And that's exactly what our situation was. I don't, I forget the exact details but I'm pretty sure the other aircraft and it was only yes that got the got the RA but going back you know they to come up with a system that works this.

14:02

Well was taking a long time but actually they developed it quite early on First they want to like a ground based system. And it was actually called be CAS and was like a beacon based system but I mean doesn't work over the sea Does it? And also there was issues with how busy the beacons would be.

14:19

And that's a big part of this is the the data that has to be transmitted rapidly between the aircraft. And then you imagine some of these systems were designed a long time ago and it has to compute Very quickly if there's going to be an accident but the airspace is so busy.

14:33

I mean, it must be computing all the time. Yeah and initially when TCAS was implemented, there was a lot of nuisance and you could even say spurious. Triggers of the system, which is not good because empires Blend that it was annoying and maybe not to follow us. I mean, people are getting them off boats that have transponders, right?

14:54

And this kind of thing, right? Yeah. But eventually, we’ve up with this like incredibly robust. Airborne collision avoidance system which may be superceded sometime in the future. Now, ADSB is coming out but still going to use basically the same principles that we've been using for. I don't know, like 40 years, the years.

15:14

Well, we know, yes, something like that. And then i think you're a control. Reckon, it's Decrease the chance of airborne collision by like a factor of five. Out Most of saved. A lot of lives, definitely, and I think Pilots now our generation pilots definitely love the system. And it's so good that it's actually the nuances of Of it which of course problems which is because it's such high density traffic.

15:40

Situation that we're flying through. Now, the systems just needs tweak in every so slightly just to stop as it being so annoying. So the fact that it's safe isn't even in question. Yeah. So yeah, I mean, I don't know if you remember the mid-air accolision that sticks in my mind, is the cessna that hit an aircraft in the circuit in the states and then there's a picture of San Diego.

16:02

And it was as a picture of the southwest airliner. I can't remember if it was a DC9 like on inflames going down this booty have visual contact with that right with that session 172. Okay? And they think there's a lot of confirmation like oh yeah he's gone that way or whatever and it's actually underneath them.

16:21

That was like, 144 people. There was another DC9 with, like, 80 people who died in the 80s, but this is when TCAS, basically different been developed, but then it was like accelerated. And then by the end of the 80s, we had we had like the the TCAS system Almost that we know now.

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16:40

Faults

So, It's really simple for us to use works really well. Any idiot could kind of grasp it in a few, a few minutes. However, like most of these systems, if you, it's good, if you know the memory drills, I mean, you have to not good, it's mandatory. But if you just understand slightly deeper, The system that will give you a much safer use of it And I'm only talking just scratch the surface of it.

17:05

So yeah, if you just fly in the green you'll be safe. But a couple of things like the RT and how air traffic controller involved, if you just slightly understand that That's going to prevent. Potential accidents. Which ubiling in was in there was a mix of conflict. Yeah, so my understanding now, is that extra control if someone reports TCAS RA air traffic control will just sit back and not try and issue.

17:28

Yeah my experience is totally the opposite. Really? Honestly it's totally the opposite. I found the controllers really defensive, okay. So they start talking and they start saying, no, no, it's not a problem. The bottom line is once TCSRA. Activates yeah. You ignore ATC even if they're screaming at you, even if they said Ignore TCAS.

17:55

The the law aviator Air Law is that you were follow that TCAS system. So my questions you is uberlingham was 2002. Yeah. Was that in was that made law after uberlingen or was it? It was definitely the law in the procedure joining uberlingen and however, Thing about air law is depends where you are?

18:15

Yeah, well yeah yeah was was depends whether things are standardised. And the Russians had a different idea. So the RT you need to know your RT as part of the memory action, Like to the letter. And you need to be able to What makes like, Always gone about unreliable speed.

18:36

I mean, you always do what air traffic control says but this is the one Chance. You've got a snap out of however many years of listening to our traffic control and go. No. Because in some countries they will ignore you tell you to ignore tcas , something like that.

18:50

The other thing is, That in any other situation. Don't say TCAS. Which is a really bad habit that pilots have gotten here all the time. Yeah. So you said that. When you see proximate traffic, You'll start looking for them. Next minute, air traffic control to be helpful, say others crossing traffic that and they you will always hear people read back.

19:12

Yeah, we've got him on TCAS. Yeah, but the word the phrase TCAS should only be used when you in an RA manoeuvre. Yes, that's right. Yes, yes. It doesn't help. Yeah, because that changed as well. Didn't it? And so, so, yeah. So I have to sort of consciously So say just copied.

19:27

Thank you. Yeah. Yeah you can say we visual or visual or even though when you IMC, I guess because you so anything but TCAS I'm yeah, don't say the word TCAS, I guess everybody. Oh, it doesn't, but it should get everybody's like blood pressure at basically, everyone should get that startle factor.

19:47

So that's our safety. Net air traffic control, have their own safetinets. They have like short-term collision avoidance, which is a bit of a wider. A time that the radar system will predict things like their own TCAS but yeah it's a bit it's two and a half minutes in advance of an ever.

20:06

Collision collision. And now we're moving into aircraft that will fly the tcas manoeuvre for you. Yeah, we already have that. Yeah, I'm so talking as if it's the future but it's on A350 A380. Obviously it'll just fly the manoeuvre. So, We've got high performance aircraft now especially like a hear the seven, three, 737 max is just so powerful, so you've got we've now got really high rates of climb aircraft when sometimes we don't want them, especially an upper air space and in RVSM air space, so TCAS.

20:43

Doesn't know. What we're intending to do even though the FMS does know, we're going to go into an out capture mode. So TCAS, now, often tells us off It when it thinks we're going to have a collision when we know full well, we're going to level off. Yes. And say that's something that probably will be developed into future versions of airborne collision avoidance system.

21:06

Of preventions better than cure, right? So not having high rates of climb. Is the most. Is your biggest defence against having a t-cast most of the time, because I think 80% of TCAS RAs, Are. Preventative RAs. Yes. As that make sense and they're reducing ours, IE, you've got a high rate of climb towards the level off.

21:29

It's just asking you to reduce your rate of climb, reduce your rate of descent, which you said earlier early versions of TCS actually that all warning was reduce climb But people would always go the wrong way because they'd hear the word climb. Yeah. So then they changed it to adjust vertical speed adjust, right?

21:47

Which always meant reduce vertical speed but that was too ambiguous. So now we just have “level off”. Yeah. So it used to say, oh, choose a lower vertical speed, like, you doing 3,000 feet a minute. So just choose 1500, but now they've sacked it all off. And it just tells you to level up leveller because it's Because it's easier pilots understand that.

22:07

Yeah so it stops you climbing order to send him just for a minute and then Say it was a major problem for a while that the most common RA was for you to adjust vertical speed. But a significant proportion of pilots would go the wrong way. Wrong way, not into the green.

22:25

And the other thing is they'd overreact, So it's smoothly and promptly just inside the green band, but they'd go. They'd have the start of factor, I guess. Just they remember uberlingen, and they'd go for it. All stick. And then, as you've already said, then they cause a another RA with another level, because they go too hard.

22:44

Yeah. Yeah. But I thought you manual actually says, just into the green band. Yeah, that's your goal or just out of the redband in my even second. Okay. Yeah, exactly. So TCAS is so good. We're sort of creating a little issues within the system of TCS. So having some sort of understanding a belief, the surface of how it works.

23:05

And how it interacts with ATC, definitely makes it even safer system. But it but it works really well. One. One little thing that I wanted to mention earlier, which I forgot about building up our situational awareness. You know, looking at the navigation display was the accident that happened in Milan Linate.

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23:25

Linate Airport Disaster

I remember oh, like this. Yeah. So His first tragic, really, there was a private jet, which was Somewhere where it didn't think it was. It was like this foggy day. I can't remember how long ago. This was probably 20 years ago. Up by essentially. In the low phase, this private jet thought it was on a taxi labour, It was actually on the active runway.

23:49

A traffic control. Cleared Scandinavian SAS to take off. And unfortunately the SAS hit the private jet. They had a collision on the runway. Big fireball, but because of the low vision of the fog, nobody knew that the crash had happened. Even after control couldn't see from their position that a crash had happened.

24:09

And they actually, then cleared, the next aircraft to take off, which was a left answer. And the left hands refused to accept the takeoff clearance because his SA was so high that he hadn't seen the magenta of the white diamond of the SAS like get airborne. So you know he would have seen it say yeah.

24:30

Plus zero one plus zero two. So yeah. So he refused the takeoff clearance because he said that German situational NS yeah. And i think tcas is used same much like reigning up on anything. Yeah. And especially low visit. It's very useful. For the SA now in the so with ADSB, automatic dependence valence broadcast, aircraft, that can accept that information onto their ND.

24:57

They have like a They have like an enhanced, what you would say, Ticest display tells you Might be wrong about this. I think it tells you to call sign and the type okay and the altitude probably wrong about one of these but really, really enhances your SA that information is coming from the ADSB which is different to TCAS but a future generations of TCAS.

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Future

25:23

I probably going to use. ADSB. So, the problems always been since time began, which is How do you solve the problems of? CNS, communication, navigation and surveillance. So, we've already done a podcast on A communicate, we VHF and some of the limitations of that VHF is on radio. Communication is, is a really old system, but works really well and that's one of the That's one of the main defences against aircraft.

25:51

Collisions is just read backs. You know, it's just it's just talking to air traffic control and coordinating everything. Yeah, navigation. Obviously, we used to use radio beacons and now we're moving towards. And performance base navigation. So Where we are in in space and time the aircraft now, knows better.

26:13

Then the ground knows because of our GPS input. So we can not from the ground but from the aircraft, we can tell other aircraft where Where we are better than we used to be able to. So with ADSB, We can have a like, a more accurate TCAS because a GPS position, basically is so accurate and then surveillance used to be done by.

26:33

This yet primary radar. Which would like, you know, developed in World War, I would would ping back if it be a dot on a screen. Yeah. And then you've got secondary radar, which uses the transponder. So if you interrogate a transponder, it decides, whether to send back information, like, yeah, I'm here and it can have lots of information sent with it, but definitely sends back, it's it's altitude .

26:56

And that's what TCAS uses, which is transponder. But the use of adsb in the future, He's going to just mean it's like broadband for aircraft. Basically, Lots more data travelling between the aircraft other aircraft and the ground. And say all this airborne collision of avoidance systems are going to probably start to use that.

27:16

And then if you think about like drones, like if they had ADSB on, you can have a TCAS against the drone. Yeah. You know whether it was supposed to be there or not whether it's just You know, what is already? A very sort of safe system. It's probably only gonna get even safer and even better.

27:31

They did get to. So TCAS 2 is what we're talking about. TCAS is just TAs and it was some regional aircraft had that but TCAS 3 was supposed to come in at some point and had horizontal resolutions but basically you don't need them because everything can be solved vertically.

27:50

Yeah but with I think it's called ACAS x at the moment is what they're calling it. That's like the next generation of airborne Collision of avoidance system because That's the umbrella term TCAS is almost like the brand name. So, if something else can solve airborne collision avoidance, that will come under the same umbrellas, it'll be some changes in the future, but the point I'm making is ever our sa .

28:11

A situation awareness that's coming from this pretty rudimentary like, pings from transponders. He's going to be enhanced by a ADSB and It's like a, it's so many layers of cheese in front of the, actually, using the TCAS system that keeps us safe. Yeah, other things, air traffic control, you know, like, they don't know, we've got an RA, but now we have the ability maybe to download it to them and it pings the same.

28:35

We've got an RA. Yeah, and so be all sorts of changes to it, but all these things have to be You know, I think they're basically proposing to change nothing as far as the pilot is concerned because the simpler the better. Yeah. You don't mess with it. Yeah. But the algorithms that run in the in the TCAS haven't been changed since the 80s but now the computer power is so much better.

28:57

You can have much more accurate computations about closest point of approach and stuff like that. It's definitely some changes come in. But as far as we're concern hopefully I'll just be flying the green. Yeah, stupid. Simple for us. Yeah, first pilots. So I think what we're going to talk about now Is how it managed to go wrong.

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29:18

Überlingen Mid-Air Collision

Yeah. Even they taste was well in truly involved in the accident. Yeah, the sad sad story of uberlingen is sort of referred to as the uberlingen crash, but yeah, uberlingen was the town on the ground. On the Swiss German border. On Lake Constance, where the debris of the aircraft fell.

29:37

Yeah, you've maybe done a little more research than this on this to me I sort of Feel like I know this story quite well. And this obviously world documented on Natural, geographic air crash investigation. You know, this quite a lot of stuff out there on it but You want to broadly so talk about.

29:55

Yeah happened. It is well documented because it's very dramatic. And like,, there's been plenty of films. Including did you know an Arnold Schwarzenegger film? About this about this. I think I might have known that. Yeah, I didn't know that. So I need to watch it. Now it's loosely based.

30:13

On, on this. It's a 2017, but Yeah. It's no. What's it called? I've written it down. I feel like I might even seen it. Aftermath. And did Arnold Schwarzenegger play the controller think? Maybe. Yeah, I've seen it. I've got feeling I might even seen it. Well, But I need to watch it.

30:33

Yeah. So, It's well known. It's, it's Dramatic in its in that sense, it's addictive. So there's a lot of films and podcasts and That plays and whatever, all written about it. Likes. You see after learning about it again. I think probably last time I learn about it was pretty me being an airline pilot as always becoming an airline pilot.

30:58

It's really given me. It gives me that. And, But i are basically lose. Sleepover it? Yeah. And because Our routine day job, which I'd like to say take incredibly seriously still leaves you a bit disconnected from the reality of what you do in sometimes or what could go wrong.

31:21

Yeah. I don't think it changes anything about your approach to the job. But, Definitely gives it a bit more. Makes it a bit more vivid, so, Like you said, do you like first 2002? Of aircraft taking off from Moscow, to go to barcelona. With 45 children on board as well as other people.

31:43

The school trip. Wasn't I think or yes school trips Barcelona. Yes. The children had like one their place on this trip. And for their achievements. And i also they probably been picked because they had well connected parents and bear that in mind. So, they're going to Barcelona in the evening and Like sliding doors or whatever but they're they'd missed one of their connections or it been late and this was especially charted to get them there without delay.

32:12

So the air line, the Russian airline Bashkirian. Yeah there you go. And they're flying, the Tupolev Tu-154. Which is amazing Russian aircraft that they basically had to build and design in Russia during the cold war and fly around Russia. And it's actually designed to go in like rough strips, can like land on gravel and stuff even though suggest aircraft is like, super high performance, they had like a thousand of them in Russia.

32:39

So I guess the Russians loved it, really? A little try. Try jet. Try engine thing. I don't think I've ever really been in close to it any of these things and well, they were still flying until About 2010 are likely things. So, This airline no small outfit had about 33 aircraft okay, maybe like 13 of these four of them on the flight deck.

33:03

It's a training flight and flight. Yeah. So you captain left-hand seat and the chief pilot in the right hand sea, How many times in these accidents? Is it like some combinations? Like that? Some yeah, they have a flight engineer and for no reason. There's a copilot super numerary so I don't know why he's in the flight deck but There's even some.

33:23

Ambiguity about who the piloting command was. And I You know, i just throw that in there as to whether that is any kind of contribution. So maybe, yeah. As to So they're going towards Barcelona, it has to be a training flight because I say, I guess they think Barcelona is so crazy which it is and they captain has to have two supervised visits for they go.

33:42

So that's why they're chief pilots going. Okay. But there experience flying outside of Russia is like really limited like they've only done a handful of trips each I think they're chief pilots only been outside, Russian territory twice, right? Or something but he's checking out the captain to get Barcelona.

33:59

So even there experience outside , so Russia. Is slightly limited. Meanwhile, DHL 757, we've only two people, two pilots on boards, taking off from Bergamo. And to fly north over the Alps to Brussels, and then imagine that this Russian aircraft is coming, kind of southwest generally towards Barcelona from Russia.

34:20

And it's late in the evening by the time they get towards this piece of airspace, it's about 11 o'clock at night. So, At any about halfway through the Russian sector, maybe about two hours to land in. Not long. After space, the DHL would have grab one the captain of the DHL British.

34:40

Yeah. And a Canadian first officer 757. So at this point in in history, yeah, the DHL have Had. TCAS for a while and they like you said have been training it in the simulator a lot. And so they may or may not have had one in real life, but in every check, they're doing their.

35:01

Yeah. Now If the Russian airlines want to fly outside of Russia, they have to have TCAS because as you said is been mandated, yeah, about the time in the millennium but in Russia you don't have to have TCAS. So, The Russian aircraft has got TCAS. It's been fitted. However The pilots have and the Navigator, the sorry, the flight engineer have done the I want to say CBT (computer based training).

35:27

They've done the That they've ticked a box somewhere that says, they've done the learning. They've done the learning , They've never done one in the simulator because guess what? The simulator doesn't have TCAS fitted to it. And there it's their exposure to TCAS is like incredibly limited like, The amount of sectors, whether even done a flight with TCAS on board is like a hand like, very, very few.

35:51

So, That's his aircraft approach. This piece of airspace, Simsuric controllers. Below. And well, there's one actually bases. One, this is another factors that it's always, massive is always the holes of the Swiss cheese and they left the Swiss cheese. Well, so this this unit used to always have three controllers on And it became, Common.

36:19

That the controllers would take it upon themselves to for one of the three to just sleep for the entire shift. Because then as they alternate day after day, one of them's, getting a free, a free night sleep, and then on these deep night shifts, Then due to personnel limitations, there was only two in the control room, shift?

36:40

Yeah. And for, however, long that had been going on, but still, the controllers had decided that they one of them would still sleep for the entire shift. There's only one On duty. The same time maintenance returned up, they're like “yeah, we need to do some maintenance on the, on the old radar there”.

36:58

Yep. To the radar goes into this thing called backup made, I think or degraded mode. Another hole in the Swiss cheese. Okay? An integrated mode. The radar can only do seven miles of separation, rather than five and unbeknown to the controller. The STCA short-term collision avoidance visual warning, which goes off at two and a half minutes prior to collision.

37:26

Doesn't work, doesn't work. But all one that goes off 30 seconds prior to collision does work. Now, there's a little airport down there, which I've flown into called Friedrichshafen on Lake Constance, Add This controller also has to do the area control for that. So guide the aircraft in onto the ILS, basically.

37:47

Um, but no problem because it's 11 o'clock at night and Friedrichshafen doesn't have any inbound traffic. It's part from some little airbus shows up and says I’m late and needs like vectors towards Friedrichshafen. He does that. He's working two radar screens. I think it looks like two stations.

38:03

Yeah. And So, A DHL request climb 360 and the Russian aircraft is at 360. Yeah. So, The controller is trying to co-ordinate the fact that two aircraft are going to be at 360 because he delays one of them That the climb for a minute and he's trying to get into touch with Friedrichshafen tower.

38:27

To hand over this airbus. He's coming into land. But every time he tries to use the phone, it's not working. And I don't know if that's due to this maintenance or not, or the Friedrichshafen just aren't picking up, okay? So, he keeps getting distracted. And then, just at the wrong moment.

38:44

He gets quite heads down in that problem of trying to contact Friedrichshafen Yeah. And he misses the first part of this of this TCAS. Yeah. So the two aircraft to fly in towards each other and simultaneously. They. Both. Get TCAS RAs. Yeah. And the DHL. Calls “TCAS RA” and their controller.

39:09

Doesn't hear that because he's busy with the Friedrichshafen situation. Yeah. Next minute, he notices of his own accord that these two aircraft are going to collide or. Yeah. At least they're heading towards each other. So he instructs The Russian aircraft, to descend. And to fly level, three, five zero, due crossing traffic and expedite.

39:32

He doesn't say emergency or avoiding action or anything like that. Up to the Russian stars to descend. And, This is now whilst the DHL is starting their. Manoeuvre to descend send. So just to clarify that say the Russian aircraft, They were instructed to climb on TCAS. Was that right?

39:57

And they were contradicting that by following the air traffic controllers, instruction to descend it all happen at the same time and while. Basically control is distracted. These two aircraft. Get a TCAS RA. Yeah. And the DHL aircraft is told to descend. Yeah. And the Russian aircraft is told to climb.

40:16

By the TCAS system, yeah. The. Air traffic controller wheels. This chair over sees that something's going on, has missed the fact that DHLs called over the radio TCASRA And to resolve the situation. He decides to tell the Russian to descend, fly level three five zero. I mean it's 50 50, isn't it?

40:34

I think so complete 50/50. So the Russian decide even a 25/75. Because if you'd have contacted DHL, yeah, with a conflicting instruction they might have ignored him. So DHL down game involved, because They can hear the air traffic controller, trying to deconflict is what we think happened. Initially. This.

40:57

What? I'm just describing now and folds over seconds. Yeah yeah. And now, An aural alert goes off for the controlling now which he never heard, which is totally useless anyway, because it's too too late for him to really do the for the controller to provide any Useful instructions that would result in a thousand feet of separation So it's going to be a loss of separation.

41:18

Say both aircraft to descend in. And the TCAS can see that they're still on a collision course. And so it tells the DHL. To increase the rate of descent. Hm, which they do down to 2600 feet per minute. And it now tells the Russians. To increase their climb. Even they they're not climbing, they're descending.

41:43

Now, the Russians. And CVR shows that they're a little bit confused about what to do. Yeah. Yeah. There was Can I say that there is a conversation about? It is a concept imagine you've got conflict of like you got a captain Chief pilot who's the training, captain examining, kind of examining this guy Two other pilots, well, Pilot and fly engineer all in flight deck.

42:09

This is happening pretty quickly. Interestingly the co pilot this 757 was PF. He went to the toilet . And literally, as he sat back down, And the RA was beginning, right? Now. What's amazing is these aircraft are not just at the same level. Then now descending. Yeah. But, They could be descendent at any rate.

42:34

I find it. Unbelievable. They managed to collide, like, I mean, So, I could DHL chimes in and says, Something about TCAS RA, I think they say unable to guess already. But then, in the next few seconds, the controlling gives visual. Information. To the Russians. Hmm. And says that. The DHL aircraft?

43:01

Is i think one o'clock or two o'clock? On their right side, and it's wrong. Yeah, they're on the other side, decide. Yeah. But the Russians actually spotted in the end. And that's when they start to start a climb. But it's too late, basically. So the entire vertical, stabiliser of the 757, Basically goes right through the middle.

43:25

Yeah, of this Russian aircraft, with these children on board in the middle of the night. So, the Russian aircraft is sliced into like four bits, And the 757 has no fin goes on a little bit. And just getting into a spin, just goes nose. First into the ground, 70 degrees nose down.

43:49

So, Before I talk about the aftermath, you know what, what could we unpack about that? And I mean, for me, it's I like to talk about the Swiss cheese, but there is so many little things in that, they're just remove one of them. And it probably doesn't happen. Remove that airbus going into Friedrichshafen and remove the maintenance guys in the air traffic control centre.

44:11

Removed. The The guy who's sleeping the night, he sleeping removed, the Russians, sort of following ATC rather than TCAS. I just anything. Just one little thing would probably so the Russia. So it's easy to blame the Russians, right? Yeah, I don't think you can really, I mean, but the stay had they didn't really know and they weren't required by law.

44:32

Really what? What TCAS is about Now, there manuals had about three conflicting statements in them. One that said, Be ATC is basically the final say, but another, that kind of said, you would always follow TCAS. But then another that said, you should look and try and see an avoid aircraft rather than that's your last line of defence.

44:55

So it was not objective and a must that you absolutely follow TCAS, which I think answers when you questions from earlier. So, In terms of air law, you just got a total. Fuck up there. Where The Russians are. Allowed to do whatever they want in their own airspace and then they're obviously transit in other airspace And it's not been mandated or, it's not absolutely clear what the procedure has to be.

45:21

Yeah. Another nuance now in TCAS 7.1, they changed the reversal logic. And or they updated the reversal logic so you can get reversal in TCAS but it used to be that if you if you got too close, the TCAS thought that the it's too late to command a reversal but now it will up to a later.

45:42

Point realise. Oh if one's not following out, I'll switch it around. Um because the DHL could have gone into anything of climb. Yeah, it's just bizarre that, you know, you can understand slightly two aircraft hidden each other both flying level. Because with the aeroplane flights. So accurately, but the fact that they were both in a descent, I mean, I I can't even compare, I it must it would be like two goalkeepers at different end of a football pitch, both kicking the ball, and it'd be like the balls hitting each other.

46:11

You know, be the amount of air and space up there is just so vast. Yeah. I mean, chance of two aircraft in each other. In, whilst in a manoeuvre, is some art doubtitude. It's just It's just incredibly bad. Look really. Yeah, it's horrifying. What will come on to? Another usually sleep over.

46:31

I also find A harrowing about it is that there are other aircraft that were flying around. Is a clear night that say they saw oh yeah saw the flame. You know saw the explosion basically. Yeah I mean that would just it's in July oh just stay with you forever.

46:47

Like seeing that you know it's like flying on a clear night excee hundreds of miles To see that. And and oh, yeah, horrible horrible. It just impossible to engineer this situation. Going back to the history of TCAS and mid air collisions and so on, it's it is amazing that they happen at all because I've said before, we're so used to live in on a 2D in a 2D world.

47:12

It's kind of hard to imagine how much volume there is up there. Yeah. So there is a lot of space, but Aircraft tend to congregate together, you know, in the same circuit pattern in the same, airfield the same time. Up and they're kind of attracted to each other. Yeah, you know, these, these all these layers that prevent aircraft here in each other.

47:33

And have to be there because otherwise we would all be at the same place at the same time and and that that piece of airspace there, you believe in it is a very busy bit of airspace. And although it was 11 o'clock at night in July For the to be one controller on.

47:49

I don't know too much about air traffic control but That that does strike me as as As not, right? I'm always going over that bit of airspace high altitude. Yeah. So there has to be all these things, you know, just the semicircular rule about what altitude you fly. Yeah.

48:08

And you read backs. Your the radar. Then you've got your STCA short-term collision, avoid the system, you TCAS, and so many layers that in there. That should prevent this from happening. And then, just the fact that they happen to Be so close to each other. I mean the tail of their 757.

48:28

I mean you talking like Couple of meters and it would have been a near miss or something. So, That kind of tragedy. I think difficult for humans to kind of understand. You know, in terms of our aircraft safety. Accident reports of what we go on to decide. Like, you know what what's happening.

48:50

So the next thing report didn't come out until 2004 and that's where we start to draw conclusions from and In the beginning, the air traffic control. Company responsible for air traffic, control that did. Basically blame the Russians which didn't help. What happens next? As there. Final extra reports coming out is kind of unbelievable.

49:12

But without getting too graphic, let me just Tell you what happened in the days, following the accident. Imagine you've sent your children off on an aircraft. He told that there's been no survivors and you know, quite common. I think a lot of these parents didn't believe it. The Russians flew them out there like the next day or something.

49:31

And they get to the site and this beautiful countryside. And of the site of this, this crash. If you split a spread over quite a wide distance, the the tupolev aircraft And the Russian is just join in like the the search effort. One gentleman. Vitaly. Kelly of. Goes to find his wife, his daughter, and his son.

49:58

And straight away, just Thus starts looking for for them. And he finds his daughter. In the woods. Wearingthe little necklace that she wears is young tiny little daughter and later on Basically finds his wife and his son as well. So, For a human being to be able to comprehend.

50:18

Really, what has unfolded to fly to this? This piece of countryside, like far away and, and your families lying there. You know, in the, in the days after it's just, it's incomprehensible, yeah. So the edge trafficking controller is obviously Most weird. He needs mentor treatment basically for being The edge of controller, he was responsible, at that time, the one on duty.

50:47

And, The parents had turning up to the side of the crash. And, You know, totally destroyer and there's probably a lot of anger. And the father of, if those of that family vitali Kelly of wants to me with the air traffic controller and obviously that that doesn't happen and and refuses.

51:10

And then over the next few years, you know, bits of the Accident report, start to unfold and so on. Just a few months before the final extra report. Years later. Vitali of decided to return. To that same place. And hires a private detective. To find the air traffic controller.

51:32

And decides to go and confront him. Turns up to his house. Where he himself has got three children. I think the air traffic, controller. Neilson is his surname. Confronts him in his back garden. And stabs him to death in front of his own family, then he dies within minutes. In Front of his children.

51:54

Say I said, like really terrible. turn of events, it's not really related to the aviation necessarily. But then the story gets even crazier. Because, He's arrested and he goes to prison. But he only he does like a couple of years. Putin lobbies to get him out. Yeah. And he's Has this sentence reduced for diminished responsibility.

52:21

And then he gets lobbyed gets out, then he goes back to Russia. And becomes like quite a high ranking politician. Yeah, there is area and then gets like a national award like one of the highest awards for his region for his services in politics. And, This is all sort of explains why you can see him be an interviewed on multiple locations in high definition.

52:46

Talking with complete victory, all about that controller like talking. And with no regret, remorse whatsoever about the murder that he committed. Which is something I don't think I've ever seen in my life but before which is like, he's not locked away where you can't hit. He's shouting from the rooftops about how proudy as of what he did and seemingly as the support of the people who are You know in his country here appointing him on TV and so on and say the Russian is like have quite a different response, Nationally to the accident and and his involvement in it.

53:24

I don't really know what to say, like it's crazy, it's a crazy story and I think. Good that, you know, let's say this last bit is not really related to TCAS but Is such a dramatic story. I think admit actually being Possibly the most dramatical. Yeah, exactly. Aircraft accident.

53:44

I don't know. Most harrowing , aircraft accident. It then invokes like so much emotion. Yeah, in the people who Survive effectively. But they didn't know how to respond. Either nationally, or on an individual level because there is no explanation, your average aircraft accident, like to me, like a road traffic accident, you know what I'm like about speeding.

54:08

A road traffic accident, you know, with with fatalities. It's just so meaningless. It's like it's not cancer, it's not, it didn't have to happen. Yeah. An air traffic. Accidents are always the same. They're just I think if you lost somebody in one, you would never really understand why on a human level like why is that happened?

54:30

But this one, with all the, the my new Things that came together to allow it to happen. Is even more unexplainable. Does that make sense? Definitely. And so more. Upset in shocking. Yeah, shocking. Yeah. It's a shocking story. So for me, all it does. Really maybe as I've got older is In.

54:56

You know, sad. Sadly, it posts like the human element back into the job. But then, It also shows you that How amazing? We can do. Some some geeks who've probably never flown a plane in their life, like, came up with the algorithm, like in the 60s to detect aircraft, collisions and fit omni directional, aerials to top and bottom of aircraft then And then some genius, you know who knew about the semantics of aircraft displays was like kept flying to the green.

55:29

Yeah. How many lives have been saved like that? Despite that tragic story, TCAS has been a brilliant edition to The aircraft and saved many, many lives and accidents. So long may continue. Yeah absolutely and it's moving promptly just inside the green. Yeah and keep it really simple for those pilots for risk, guys For me.

55:50

Yeah. That's it? Really? That's TCAS. All right. Yes.

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Airline Pilot Technical Theory Adam Howey Airline Pilot Technical Theory Adam Howey

ILS

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00:02

Adam. Sam. ILS. Instrument landing system, ILS. Do you like ILS approaches, who doesn't? Why do you like them? They’re low workload. So easy. Is it because we've done say many, or is it just so well designed probably a bit of both. But it's just too easy. One thing that fascinates me, which I'm sure to talk about is how long they've been around.

00:29

Oh yeah. How long well since like the second world war? No way. Yeah. And they're still liked. Kind of standard. It's still like the most common. They're still better than a anything GPS. Yeah, they did. So simple, really, but so clever. And Works really well like, say considering a industry where you would think technology in Adaptation with technology is right at the forefront.

00:55

Actually, we're still using a system from 70 years ago to land. Yeah, I understand. It's a very elegant and sophisticated implementation of analogue, radio engineering. Hmm. So it's old, yeah, it's really old. I'm either question which I had previous prepared for you. Whether you like the or not so you've obviously we do a lot of them.

01:16

Probably what 90% 95% of approaches. At the moment. Yeah, my next question was in 12 years of flying. Have you ever been let down by one? Have you ever had any like Failures or troubles with them. Hey. It's the pretty reliable as well considering this so old it kind of like the system works.

01:36

That's what impresses me the most about. It really is like Just such a simple, beautiful system, that's been around for so long that works. That doesn't really. Fail. It's just easy. Every passenger out there, the likelihood is that you're going to be using this system whenever you're sound on an aircraft.

01:56

So, it's talk about ILS. I think we also have to talk about how to land a plane. Yeah. Okay. Because 9 out of 10 times, this is what you'll be doing. You said Do you like them? Well, what's the alternative? Well, the alternative I suppose, the alternatives are some sort of RNAV GPS approach.

02:15

Or a more traditional non-precision approach, like a VOR approach or an NDB approach. Yeah. And then I suppose the only other rare options are like visual approaches or circling approaches. It's been around since the second world war, but this is the only precision approach. Yeah, that exists. Pretty much, yeah.

02:35

Everything else we call a non-precision approach. Yeah. And comes with a little bit of a headache, quite a high percentage of accidents. Come from non-precision approaches. Don't they by their nature? They're just slightly more complicated. Slightly less Reliable. Yeah, the chance of having lessed off often thinking action or can specifically controlled fly into train on a non-precision approach.

02:56

He's like 10 times higher than a precision approach and then if you move to a circle and approach for a visual approach is higher and higher still. Yeah, you save it, option is a precision approach. Which is basically an ILS. But if we go back to absolutely basics, you're in your aircraft somehow you've got airborne and you've got a land.

03:13

So you need to line up with the centre line. Descend at the right angle. And you need to slow down. Visually. You can do all of those things You could find the airport. Could find some geographical features line up with the runway. You be able to see the terrain, you'd be able to choose when to configure and so on with the ILS allows to do is do it all instrumental, logical conditions without seeing the runway at all.

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03:42

And it is magic. We've talked to separately about low visibility operations, but Typically on an ILS, you'd be you could get down to 200 feet above the runway. New basically almost at the end of the room. Where that point, yeah, that's how it feels. And but when you see the runway come out of the, the clouds and the fog, or that moment is pretty special to have lined up like that.

04:06

But if we didn't have any Radio navigation systems and we're doing it all visually. Most airports have a PAPI or a VASI system where they send out. White light and red lights. You're following the right descent angle towards the runway. You'll see two reds and two whites, And if you're a bit too high, you'll see three white or even four ways.

04:29

If you're too low, you'll see more reds. But there's PAPIs always thinking. They're like a visual. Version of the ILS. If you like what the radio navigation is allowed allows us to do is hunt for the runway. Using sensors that we don't as humans have because we can't see anything because this IMC The radio nav is like listening.

04:52

For. The runway. Yeah, and if it hears a bit too much of one tone, it's too far left. If it, if it hits here's a bit, too much of the other, it's too far, right? So it's kind of light when you get up in the night and your bedroom, He need a piss.

05:07

I see that's not the right example. I was trying to think of an example where You're in the dark or you're blindfold and you can hear what you need and you move towards the sound. Yeah, that's what the aircrafts doing. Yeah, it's here in the Tones of the glide slope and the localizer.

05:23

And it's like hunting, its way in towards as it narrows intowards the runway, right? Yeah. Yeah. It's really old and very analogue system. It's kind of genius. I was genius. So delivers the aeroplanes. As you said, 200 feet or the original Know, ideas delivers, the aeroplanes 200 feet and then you then will pick up the the lighting of the runway or the PAPIs and carry out the landing visually from there.

05:47

I mean, it's incredible, really. It's like on Star Wars. Which came after the ILS. Then yeah. So long. Okay. And they have on our sci-fi, they have those like tractor beam, which is where they kind of like lock onto the spacecraft and just pull it into the spaceship.

06:04

Yeah, it's basically what the ILS does. Yeah. You're in like a beam vertically. And horizontally. And you're being pulled in effectively, with the use of the aircraft systems, like the autopilot, for example. Yeah. Towards one dot like it, where you're going to touch down, In the touchdown zone. And then, Later, iterations of the ILS at later categories.

06:27

Later versions have reduced. It even further. We talked a little bit about this in low vis. Reduce miinimum altitudes even further. Now, to the point where some FLG don't even need to be able to see anything. They'll just literally land their aeroplane. I mean that's a facility there aircraft as well.

06:45

But, but it's the same ILS. It's the same ILS. Guiding, Guiding the aircraft all the way down to to landing all the way down to search. Now, I think the radio aspect of the ILS, has been updated over the years for the fundamentals of it. Exactly the same. If you ever seen the glide slope antenna, No, not I I've seen it but it it doesn't stand out yet.

07:08

It's about 1000 feet from the threshold, okay? And it's to the side of the runway, okay? And it's hard to spot but that's Projects. Three degrees. Thereby at The threshold, you'll be 50 feet. If okay, I see but the localizer antenna. Everybody can see that. He's plenty of accidents, where the localised antenna have ended up in the aircraft.

07:29

Yeah, or hooked under the tail or something because they're just station, just off the end of the runway on the extended centreline. You know, the far end at the runway. So the runway your landing on, it's the directional antenna of which there's quite a lot of them. They're at the far end for the runway that you're landing on.

07:45

Yep. And there. Angled. My understanding is their angled exactly. Right. So that at the threshold of the landing runway the beam is 700 feet wide, okay? So the beam depending on the length of the runway that the ILS is on the angle of the localizer beam is is wider, okay or shorter depending on the length of the wrong way?

08:05

Okay, interesting. So, we've established this kind of very simple system, which has a localised and a glidepath guide to sin. Vertically. And Horizontally. It's been around this second world war. Later, versions of also been coupled with some sort of distance measuring as well, so you can actually This addition measuring equipment or more fashioned that was like marker beacons.

08:31

Yeah. When you look at ILS theory, there's loads of stuff about marker beacons but people should probably know that. Last time, I thought about my yeah, was when I played flight sim in my bedroom wasn't finished. Exactly commercially. Now, most most ports have a DME Associated with the ILS, which is essentially, yes, add some A lateral distance from the thresholds and at the technical talk about complacency Because we do these ILSes so much, but the times when I have flown, ILS, is that don't have a DME.

09:01

Yes, not tell them on the approach that I'm like, hold on, there's no DME is my monitoring is say poor and I expect it co-located DME. Yeah. So some airports you could use a DME on the airfield, it might be on a VOR or something but most ILS is have IDME with paired with the frequency as well.

09:19

So that gives to the point one of a mile distance readouts all the way down to the threshold. These old markers beacons, you probably would have one or two like an outer marker and inner marker and do you remember on die hard? Yeah. Then they mess with the ILS.

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Die Hard

09:35

They turned the ILS off, but because Bruce Willis, He goes, there was fire basically. Like he didn't know how he did it, but he made like an approach lights out of fire, and some oily rag with some oily rags. He was like, at the end of the threshold, like, with his arms and isn't it.

09:49

A British flight crew here? Like, I think, possibly something like I follow in the procedure. Say, perfectly and the terrorists are like laughing like, yeah, and he's knee keeps saying something like Little bit closer, come on or something, the terrorist, and then they smash into the ground, right? Okay.

10:06

And yeah, it's supposed to be The British, they're crashes knit and Bruce Willis is saying like My these like, basically destroy as he watches it smashed into the ground. I'm sure they go over the, they start talking about beacons, right? Then, which would be like the ages with 80s?

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Technical Description

10:23

Really nice. Yeah, I think I didn't understand any of this but the outer beacon was Help blue, help your establish to get to the outer beacon. You should be kind of turning on to the localizer, but that it can be a various distance, It doesn't tell you what height to be.

10:38

The middle marker might be whether decisional attitude was, right? And it's Amber. And then the inner is like really close. It's like you're on the threshold sort of. That's why and these markers or more recently, the the DME would help you. Again idea of whether you're on the correct, Glide slope because it would have often have a height check associated with it.

11:01

So, as you go over the market, you should be at Say 2000 feet so you check, yeah. So forget all these markers because they're eggs but basically, I don't know what what role of thumb do you have like 10 miles 3,000 feet or something? Yeah, exactly. Yes. So on a three degree if you good at Pythagoras like on a 3 degree glideslope.

11:20

Yeah. For every mile you know, you know exactly what height you should be. That's really on that channel. 100 feet of a mile, isn't it rough? Yeah. And you should be able to. However there are ILSsers with the are not three degrees. So, just generically talking about landing in aircraft three degree.

11:36

Slope is the Ideal. Vertical descent slope because It keeps you clear of terrain and obstacles as you make your approach. Empties shallow enough for you to slow down in decelerate, on I guess is basically why three is correct? But there's plenty of ILS. Is that aren't three degrees? Yeah.

11:58

Say the guide slope can be adjusted to not be 3 degrees and then the DME helps you realise how far you are from the runway in and how high you should be. But if you're on the glide slope, you have to be at the right height. Yes, unless something's gone terribly wrong.

12:12

Yeah, so yeah. Never mind these these markers and stuff, but the DME with the slant range as well. So it's actually the distance. As you fly down that three degree, Three degree. ILS. And the technical stuff that I think this in the ATPL is that the Localizer is transmitted in VHF.

12:31

But the glide slope is transmitted in UHF. But you never have to tune the glideslape When you tune. The localizer is always paired with divided slave because you don't know the frequency of the glycerative, it's in the 3,000 ultra high frequency range. And as you know, from radio theory.

12:50

The higher the frequency, you get a nice good resolution on the signal, but you get less distance, Right? So your localises usable maybe out to about 25 miles. Yeah. But the glide slave, maybe is only really usable out to 10 miles and we might use it. But with caution, It's outside, it's protected.

13:10

Ranges. And on the char, you'll see usually depicted visually like where the 10 mile glide slope protected area is And then this localizer. And glisely. A frequency modulated and it's done in a way similar to FM radio. Like bro, you know, music FM, public radio, And there's a low above a 90 Hertz on the left of the localizer and 150 on the right.

13:37

And the aircraft like I said here is it automation? Just two tones. And when the amplitude the volume of those two, you know frequencies is is exactly equal. You're on the centerline cellphone. Yeah. I think about the engineering of that because if one of all those localizer antenna if one is Slightly more powerful because it's just not tuned, right?

13:57

Yeah. Then you're not going to be on the central line. Yeah. Say it's really well engineered because they're like, you said, they never go wrong that? Well, that I'm aware of. Why'd you saying that the other day on the approach? I was like, what's it? I'll see doing there.

14:08

I think it's more the aircraft, there's you. Well yeah, exactly see. Yeah, it could well be the aircraft. Although it's like the industry standard still. From my reading. Although I've never been there. I do believe that in the USA. There are a lot more GPS and I have approaches They outnumber ixes now from what I read, but that's mainly due to the fact.

14:29

This so many like little regional airfields and airports. I think you still find ILSes at most of the major airports but that's interesting because the I think it's 100,000 pounds a year roughly per runway to have an ILS. Okay so if you are in some on some little airfield that's a lot of money.

14:48

That's a lot of overhead. Yeah. Amongst all the other things to maintain your airport. So that's like when you fly to these little Greek islands that we we might be more used to you. That don't have an ILS even though there's no Geographical physical obstacles or anything that mean you can't have one.

15:02

It's just a cost. I think that prohibits this But with augmented GPS systems. He could technically. Have accuracy. It would be measured differently but you can have accuracy as accurate as like an auto land system. Yeah. Is potentially possible in the future and all the Capabilities basically, on board the aircraft, the ground.

15:23

Just have to have a little GPS augmented. Like gbass equipped thing. Whereas that the maintenance installation for an IRS must be massive. Yeah, big old powerful transmitters on they but I think it's going that way slowly. I think, eventually ILS’s will be faced out in favour of GPS but until they have the capability of like say being able to auto land and You know, visibility fog, and I guess it under 80cc have higher capacity on ILSs than non-precision approaches.

15:52

Maybe, I don't know. Yeah, possibly. Yeah, is he why? They but I guess so, although That leads me underlight though. One thing was going to say about the another limitation of the ILS is, obviously. It's You know, it's a freak, it's a frequency, it's a signal radar signal being sent out.

16:08

Yeah. And obviously, that can be subject to interference and it always used to make me laugh and you'll know this from flying out of Gatwick as well. If you are on approach behind like an Airbus A380. Oh yeah. Because it's so like so damn big. Basically like blocks the signals for any aircraft following behind it.

16:26

Like blocks the localizer signal, So I forgot about that. Yeah, you remember? So the Emirates just coming in the Emirates A380s coming in it like, was they had trouble with it? Like distorting, the localizer for aircraft behind? So, if you are coming in behind the A380 a traffic would say A380s coming in, can you accept the RNA?

16:44

Have approach, which obviously, it's not subject to the same. It's fairness. That was another. I'm not ahead of that anywhere else. They? No, don't think Emirates were even aware. No, the nuisance they were causing a gateway. He must just be a gateway. That's weird. The Gatwick thing, The frequency range of the ILS is band, is small.

17:01

Anyways, it's only 108. 1.1 to 111.95. If you like around London where you've got a lot of ILS or I don't know. All sorts of places you can, you know, you could quite easily pick up the wrong localizer. Yeah. Because it could share the frequency sticking with that for a second done.

17:19

So like thinking about the limitations in low visits, I think we oh we did talk about this in low vase, There's like a protected area. Because you're solely relying on the localising, the glypath to fully also land. The aeroplane that you've got basically have the aircraft On the ground like back away from the runway so they don't need to feel ground vehicles.

17:38

So they don't interfere with the signal because we'd so dependant on it. Yeah. So someone parks their massive one packs of aircraft in the way here. Yeah, it bends the signal business signal and not ideal for someone doing a low visibility approach. Holy dependant on the On the reliability, the ILS.

17:55

So maybe an ILS is like, the peak of ground-based navigation and we're moving to what they call performance base navigation. Yeah, which is all the capabilities on board. You're using the satellite network. Yeah. Which isn't on board, but everything else is on, but the aircraft is determining its position.

18:12

Not the ground based system. Yeah. NDB's have gone and we don't fly down airways that are It designated by VOR as anymore, but ILS is incredibly useful, reliable system as old as it is. But maybe that was the peak and the end of ground-based A navigation and radio navigation.

18:33

One thing that glidepth can't do is it can glidepath can only be straight in and on the constant path, you can't. There's no sort of adapting it. So, With an on other person thinking of places, like, Nice and others. It's what I call like a bendy on a, it's like a curved aren't have approach, which obviously, the aircraft.

18:53

Using the satellite network is perfectly capable of flying and it will kind of really helps. If you have to rain issues, or But I really says that they tried a variant of the ILS called the instrument guidance system that IGS And that was the first attempt at doing a bendy IL and that was a kitech airport.

19:13

Yeah. As you like, watch YouTube and stuff, just have a look at Kai Tak airport in Hong Kong. I think it's closed now, but yeah, basically, because of the terrain and the topography around there you It kind of had to I think I don't know how it works. Exactly. I think you flew like one ILS like towards the hill and then you picked up another ILS.

19:34

Which turned you on to final approach, but it was like a lot, a very late turn on finals and flew. And ILS, you flew a ILS on a base turn. That's right. Basically then you turned onto the final IS or over. Just visual when you basically flew past this Chinese lady putting a washing out like You know, probably using the jet blast to like dryer clothes dryer sheets.

19:55

Yeah, because the pictures always show that the aircraft and they're always seven fours. Yeah. I like below the height of the buildings that I find three. Yeah, but obviously Hong Kong is A good example of there's nowhere, really that good to put an airport, let alone a beam that stretches out 10 miles, it doesn't have train in the way.

20:13

So they obviously built the new airport in Hong Kong where they made an island out of. Yeah. Have nothing. Yeah and I'm sure this some like dead easy straightforward ILSs, then now. Yeah. But they tried an IGS there. Did they try this thing? Called an IGS? It didn't really delve too much into it, but it was like a variant of the ILS.

20:31

I wish was what they were trying to attempt to do, but there's been other. Try, people try to sort of tinker with the ILS. They try to microwave landing system, the MLS. Yeah. Wait, was, I think to try and reduce separation but that has been a garden and not really work.

20:44

The ILS is just kind of like the stall wart of precision approaches. It's just Just don't mess of that. Like it works. Yeah, slight limitations but it works you know And the To the way that it works for the pilot is the standard of performing in approach which is you one lateral and vertical guidance and you want it's like we said about TCAS is so simple.

21:08

Fly towards the dot you know or fly towards the line. Yeah, pretty straightforward. It's like a very simple boring computer game in a way. Yeah. So now we're moving into like the precision like approaches where they're Their non-precision approaches. Using probably GPS that Maybe it's augmented or not, but The display to the pilot it, they tried to make it look like it's an ILS basically.

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Manual Flight

21:32

Yeah. So that's how good. Not only the system was but the The best system seems to be the one where this simple as possible for the pilot. Yeah, definitely. Well, I say, I was gonna ask you like, we have it so easy. Now, we just repress a button and it with the autopilot engaged, when was the last time you try to fly an ILS manually.

21:54

So without like, on our aircraft without the flight directors, and actually just trying to intercept the localising, the glide slope manually, which you watch the first officer day? Yeah. They keep asking me like, can they do? And I'm like, yeah. Okay fine. Yeah. But in the sim. Yeah. And probably not all engines running either.

22:12

Yeah. And it's quite hard. Like I was probably Aces it. Doing my light instrument rating. Well, true story on my some kind of line training not so long ago really I was quite new back to the air bus. Those parallel approaches into Heathrow. And it was about 60 knots, wind it like 3,000 feet.

22:32

And i was joining the localizer. Manual. So raw data ILS was part of the training celibus. And i hadn't. I wasn't using enough bank angle rather than doing the right rate of turn, Okay? Because I guess I'm so out of practise like I was flying the output. Like I just wanted to get down to the localizer.

22:51

Yeah sure. But there are standards for Instrument turns on there. Yeah, I guess you can't swing over onto that. Yeah, well, I guess mine was too shallow. Right. Okay. Can I set off the alarm in the tower? When the radar? That i would go through and, and it's compromise.

23:08

The other Runway that was genetic parallel approach, right? Thanksgiving action. I really yeah, it was all your fault. Yeah, it was. I suppose that time. No only because I was new and maxed out but I was just so used to. I'm not having to worry about like rate, one turns or do you know what I mean?

23:29

If you flying raw data, Stuff. You need to leapfrog from like one instrument procedure to another almost like. So it's reliant on. You know, time in the turn, how many seconds, what rate of what bank angle will you need based on that speed? I mean, that's how people used to have to wear these things out say because they didn't have a DME.

23:47

Yeah, didn't have GPS. So they were flying. Instrument stuff all the time. But now, we kind of get Just a nice little vector on to an ILS. It opens up another like discussion really doesn't it like it's probably a whole podcast on like awesomeration and you know, it's just too easy to use the automatics.

24:04

But to what detriment are we like? Actual manual flying skills. Well, it freeze you up to monitor other stuff And if I the hardest part of any pilots career, is your single pilot. Twin engine. Instrument rating stuff. So flying around in a little twin engine aircraft. A single pilot table manual.

24:27

And it's all. What we're saying these skills that we've lost? It's all. Yeah, instrument rating skills. The yeah, i i'm probably lost. I'm not saying it. It might be able to pick them up again reasonably quickly. But monitoring the automation is important And if you're able to do that, that frees you up to think about other things.

24:48

Yeah. Mean what, you know, when you're thinking about and like a base turn like is a cabin. Ready? How far is the aircraft in front? Yeah. You can think about? Yeah, not a lot of space. Yeah. It's like say you get it's too easy. Yeah. It's too easy. But these these aren't have approached.

25:07

You can't really fly the manually anyway. No, no. So Your interpretation of what the automatic's doing becomes the challenge like wasn't doing now. So I think if it If the aircraft too violently light joins the localizer or if it turns the wrong way you kind of get a sense.

25:21

It's not it's doing something not right there, it's a little bit more unknown at the moment with the onever approaches as how it's interpreting. The database and the line that it's that it wants to fly. Yeah, whereas you know, when it's when it all your pilot is doing is hunting, the ILS signal Say it's a bit more straightforward.

25:40

That's right, summarise what we establish a very reliable sister. Expensive though, but works, even around for 70 years, still working. Well, But yeah, there are ultimately brought down in Diehard tea there. Yeah. The British British Airways thing or whatever that say open tea. Yeah, terrorists. Yeah. Yeah. If you set up in a local church, which is what they did.

26:04

Yeah. And like the interfer with the guy like plugs his computer and yeah, less and changes there. Yeah. The glide slave. I didn't know how much you want to talk about, because it's so day to day. What we're actually. Doing on on the ILS. Like, you know, how we almost like how we land the aircraft.

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Typical ILS

26:22

Yeah, I don't know how that links into. It's just such a typical manoeuvre Because that might help talk about the accident. Because, yeah, fair enough where things should be happening and yeah. Okay. So typically let's let's use some UK example, any UK airport. Where final long, let's say another labours it'll generally be radar, vectors onto the approach.

26:42

So air traffic control are going to give you headings and descent towards the island. And where does the approach start technically in my TPL questions. But you got your initial approach fix. Yes, finally approach fix. But it's different from the arrival. Nine times that attend the arrival in the UK just becomes radar vectors.

27:00

To the approach. The approach is basically a big just draw a big line out from the runway. Yeah, and join the localizer and at some point during the glide sleep. So, yeah. However, what we're getting there, we're being sort of radar vectored or positioned towards the to the approach, just kind of spacing.

27:17

And depending, how busy it's traffic, You're trying to think ahead where that control is going to send you And you're trying to look for threats like, The terrain and maybe the weather. Yeah. And you've also, you know, that ultimately you need to arrive at the right height at the right distance but you don't know.

27:37

Where the control is going to put you on that because you don't want to be above the glide slope intercept altitude otherwise is recoverable but that's hard work to capture the gly slope from above that's that's a whole different. Different to say from below, which is like standards. So, imagine you got.

27:56

So, the 10 mile point, let's say that you insert the glide slope, you're supposed to be at 3,000 feet so you're trying to judge With your experience and air traffic control, and whether and everything else. Of making sure the aircraft is down at 3,000 feet. By the time you get to that point but not too early Otherwise that becomes an inefficient noisy.

28:17

Fuel burning. Yeah, annoying people on the ground because you loud. So the game is, can I get from top of descent? To a thousand feet where we want to be stable, which is when the engine's come up, Can I do that? Well, idle power the whole way. Yeah, exactly.

28:32

Yeah. And to do that game, the aircraft control may or may not let you Increase or decrease your speed. And they may or may not give you an idea of how many miles you've got. Yeah. And nobody wants to fly level with the power up because technically then you're annoying the people below but that's the game you play and then everybody knows Pilots have got to be so good at maths so you have to just constantly be any three times table.

28:57

Yeah yeah. She's like really Easy. And i don't i there's a blazer ways to do it, probably the main way I do. So look at a 10 mile final. I'm going to be 3,000 feet. Yeah, I just work backwards from there. Everybody does a differently. Everyone works out differently.

29:12

Don't they? So, when we joining the localizer, maybe just outside that 10 mile point, It will have been given an intercept heading, which will be probably roughly 30 degrees off the inbound and then you're on your own then really. It's then down the radar vectors are over. It's up to you to get on the localizer whether that's going to be manually or you've probably got a different perspective on joining their legalizer because If you do a little bit of radar veteran.

29:36

Yeah, yeah. Because you're a trainer. Yeah. So you have like a radar display and you're you're the one giving the rate of. Yeah. They're just in the same, the displays not grace, and basically, using their Okay, the pilot is now display. Give me a rough idea. But yeah, it does, it does change a perspective because now when flying I'm kind of thinking they should be turning us now because that's normal right to start turning them in the simulator, you know, based on what about wind and stuff, do you go that to that level?

30:05

Yeah, yeah, see have a, yeah, we're going to be have a ball park mileage across track mileage, and which you would turn them onto the localizers and then you just start for when you're on the lake lies. That's great. But if you if you've not If you've turned them on to tie.

30:20

Yeah. They might be above the glide slave Over the glides that disaster. Yeah, not yeah, on the localizer. It's going to the localizer inside 10 miles and they're not yet on the glycelope. So, Technically not approved to decent well, Yeah, not a pretty to descend on the glypath until On the localizer.

30:37

So yeah saying Amsterdam I've had them like trying to get me to join well inside for miles. Yeah. Still descending above the glide slope. Yeah. But normally what, a nice 10 mile. Maybe a mile 10 mile final? Yeah. It's probably joining. So speed wise, you'd be joining the localizer out of 10, 12 miles about 200 knots 200, cowboy 209.

30:59

Okay. And then, so we talked about three degree slope which generally equates to about six, seven, hundred feet a minute, rated descent down the final approach. He really aircraft are generally back at 180 knots at that point and then Whatever. Depending on the airline, where you have to be stable by normally a thousand feet.

31:20

You would then work backwards from there for your final configuration from 180 knots. The landing gear and the rest of you flaps. Achieve. To achieve that by By a thousand feet. So how do we know we're on the right? Glide slope. Hijack. It, we check it against a height against distance measuring equipment.

31:42

To make sure that it's the correct glideslope. Because What has happened? I've never had it, but you could capture a false glide slope. Yeah, I think if it's, if it's somehow reflects off something. Yeah, it can. Multiply yeah i think they're always so the glycerate. Let's assume should be three degrees, the false one will always be multiples of it, 60 degrees 99 yeah you'd be pretty He didn't show on a 9 degree, glad so you'd beating special 2000 feet a minute, every pretty yeah?

32:13

No, I don't think I've had one but if you're capturing from above You could capture the wrong. Glideslope even. Yeah. Yeah. If that happened to be a false glidely and all this systems on board and on the ground I think try and stop those problems happening like false localizer capture.

32:30

And false closely capture and stuff like that. And then another way is eventually the radar will come alive. M at 2500 feet. So that's your chance to check. Well. Am I? On the right. Glide slope based on. Fact, that That's gone off. Seven and a half miles basically. Yeah.

32:50

So, I think that's interesting because I mean even the SOPs are written as if you're going to do an ILS. Yeah and then it's like the other approaches are an exceptions. So everything even in my mind is set up for that the way that the Arrival in the approach goes is like an ILS.

33:06

Yeah. And then you insert other procedures if you're not doing analogue, everything's kind of set up for that Mean. Even the Airbus is kind of designed to go from like parish to Heathrow. Like ILS to ILS. You just press one button and it should basically just do everything. Yeah, yeah.

33:22

That's how every day flying ILS and when I flew and you've had similar experiences like Charter Airlines, you do a lot more non-ILS stuff because you'd be flying a places that don't have that equipment. And if you fly in bigger carriers that fly to more Hubbards spoke stuff.

33:38

You do just tend to have a career full of like ILS not necessarily you'll see a lot more of that more. Yeah and there is a skill Element to that that you might lose some of the other skills. And then there's also the It might, you might just find it slightly more boring but then Going back to the statistical.

33:56

Look at it. They're truly is plenty accident reports that show how an aircraft crashed. Performing a visual approach. And then the last line of the report is a functional. ILS was available. Yeah. Yeah, the lowest chance possible of controlled flight into train should be on an ILS. But it does happen.

34:15

Okay? It absolutely talked about a couple of limitations of their Of their ILS. False glideslope, false localisers. And to be honest, I don't know if you found the same, when it's sort of researching. Accidents and incidents. There's this quite a few out there. Maybe more incidents than accidents, where The limitation of the ILS with false captures and things have caused issues, but a lot of the time it generally gets caught, like you say we're checking like the radio altimeter or something's not right percent rates too high.

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Korean Air Flight 801

34:48

Another. Interesting. Thing about the limitation of the ILS, which, yeah. When the ILS is not working, it is working. What it looks like. It's working That's a, that's another potential problem. It was a Korean Air Boeing 747. Which sadly had an accident at Guam in Asia, back in August 1997.

35:14

Basically, the crew were, and obviously, always caveat with talk about accidents, we learn from them and Everyday things better next time. It's not to apportion blame or anything like that. But basically, the crew have been told that. Of the ILS glideslope was an operative. Either than no times or from air traffic control, but they knew that it was an operative and they had discussed this in the briefing, according to the flight to the copy voice recorder However, they were confused.

35:42

They became confused because they're instrument was sharing, like, down the approach that there were actually on the glyes, slopes, so they kind of thought, oh, it's working. Maybe we could, maybe we could use it. And there's no warning flags to say that it was in operative. But basically it transpired that the maintenance staff had left the system in a test mode.

36:03

Which I understand I sent out sends our carry a signal, but no displacement information. So basically, the result is that the Flight director indications show that the aircraft is perfectly on the centre line on the gly slope, no matter where it is. As long it was in a kind of broad arc of the ILS and yeah, so they They were 30 looked, okay, and just kind of followed it.

36:26

And I think there was a sort of a That busy workload. Throughout the descent as well and not not monitoring it properly. Essentially the ended up. Yeah, control flight into terrain. On the approach in IMC conditions. I mean, talking about learning from Mistakes. I mean, you would think that that was that would be a well established phenomena that there could be a radio aid that you spend your career relying on There is.

36:55

Emitting. Perfectly valid but totally erroneous. How many sense? Yeah signal. Yeah, I mean, as surely something you've got to look out for in your career but how many times I mean, I I say I've seen it before both in training gun myself You guys? Oh yeah, I left off.

37:13

Oh look, it's working, you know. Yeah. Oh that's good because we all like ILS llike I've had it flying to, you know, some countries where the standard of the no times is a different. Let's say and you're like so does that mean it's not working? Always working, I've had it on my line, check the other day where it was, no time to runway closed ILS off.

37:34

Well, and then, so we're talking to One. Country asking them. Can you call ahead and find out? What the approach we can expect and they're saying it's one thing in all the way down the descent they're going to notice the ILS and we're saying well it's must be localizer only then and there It any ambiguity at all?

37:52

You need to take it out the flight day. You've got to keep resolving the situation. Yeah. And that was obviously the case here because there was some CVR transcript that showed there was ambiguity about whether the glycolate was working. But before you get to that situation, that has to be a bottom line that you have to be aware.

38:11

And I don't know what point in your training. And when I learnt this, but you've got to be aware that if something is no timed, I'm sure there's other accidents. Like where viawars or something? No time does As unserviceable. You do you? You do not follow them, you do not go.

38:28

Oh, it looks like it's working because clearly that this can happen. Well, this example. Yes. So literally it wasn't working. It was left and test mode. But, I mean, How crazy that test mode, just sends out carry a signal that shows you being like on the or did you know that?

38:44

No, I love any that That was a possibility. No it makes you think of like all the like tens of times that I've heard crews or I said oh look it's working you know in Yeah, I'm gonna say we would have followed it but this temptation is there to follow it and absolutely.

38:59

But like we always say about you've had 10,000 hours following and your instruments believe in your instruments and now you've got a fly, a low close roning approach. With a glide slope indication that you can't turn off. The eyes are just going to be like, oh flyer fly down, fly up.

39:18

So that's a horrible trap that they're in and like everything we always talk about reasons, Swiss cheese model, There's lots of layers here where it could have been trapped but The the trap was set for the crew if you like yeah by saying there's an ILS here's a signal it's on your Wherever the 74 is pfd.

39:37

Equivalent was right in front of you. And look, you're on the glide slope. Yeah. And there was plenty of ways that the action could have been core. And but what horrible trap to set for them, definitely a lot of Navigate for emit on. A test, but they will admit the identity TST as test.

39:55

I've seen that before you, but these guys were expecting to use the localizer part. And how unfortunate that they glide. Slate was radiating at the same time? Yeah. I don't know if I've ever I may have had that I've got memories of this happening in Naples to me, where it's no time to the glide slaves US, and you can't quite get to the bottom of it, over the radio communication with air traffic control, But they briefed a little bit.

40:22

A read the briefing from the captain. I don't know. What the environment generally was like in. Korean air in the seven four and aviation in that day. But the brief briefing seems a bit short one-sided. There's not really any identification of threats and even just listening or reading the transcripts to the brief.

40:40

It's not really clear whether Because he's talking about ILS. But I think he means he's doing a localizer. So he's doing a non precision approach. You need to be pretty clear about what you're doing, what you're doing. Yeah. And then, they end up. Trying to follow the glysely but the flange engineer and the first officer made, plenty of comments about the guys slaves not working.

40:59

Yeah. And the transmission from the tower was Join the localizer on my 06 gly. Slope unusable right but they didn't read back the glideslope unusable or anything like that. Part of it. And I think what's really unlucky is They were quite far below. The vertical. Dissent profile that they should have been on.

41:21

Not in there were quite far below. Not like too ridiculous but right where they were there was a giant hill. Yeah. And also, some of the modes of the GPWS were disabled. Yes. Because otherwise it would go off in a new since way. So some of them were going off.

41:34

Yeah. But the terrain terrain and so on wasn't going off. Yeah. Probably another episode again. GPWS, they have this single terrain clearance floor which Yeah basically if you're in the landing config near an airport it kind of thinks well he's gonna land so We can turn off all our warnings.

41:51

Yeah, which is, yeah. And the I think the air traffic control have MYS, which is also to stop and flying sales, but because that hills in the way that it doesn't, it wasn't activated for that. So, There were would have been configuring their aircraft and in the normal ways and things like that and they must have felt what you can see in the transcript They felt like something wasn't right?

42:13

Yeah. That's always the first sign of an accident is like people describe The uncomfortable feeling, something's not right? And in the end they decided to go around but they sort of half-heartedly Started the go around manoeuvre and it just happened to be exactly the wrong point and they just smashed into right next to the VOR.

42:34

Yeah, I mean, they're like feet from the VOR where the impact the ground and I think 23 people survived. A couple of cab increase survive for everybody else, died. Say hundreds and hundreds of people. What can we all learn from? Well, yeah, I mean I mean, for in general, for the whole topic of the episodes, ILS, really easy really reliable, really good.

43:00

Old stonewater system, but does have its limitations. And some traps, as you say. So beware the traps but I think you nailed a lot of it there. In what you said was just resolving that ambiguity like just making sure, you know, everybody knows what we're doing and we're not looking at that gly slope.

43:22

If it's not working, we're gonna do this and we're going to stick with it and we're not going to be tempted, even briefing out that We this this thing is going to be drawing you to this. Like you're gonna be drawn to it and you're gonna want to fly down.

43:34

It is like You know, it's just the easy way is what we always do. It just blocking it out. Other options are available as well. Do you have to fly the localizer only? Yeah, you have to fly the ILS that day. Yeah, they weren't visual. Be, if they were clear about the approach they were doing and they were set.

43:52

The bottom lines were set. Yeah. Then they would know distance to the threshold. They're too low. And they need to go around the communication in the flight deck, you know? And the allocation of duties stream PF and PNF, if the PNF has they were called, then the pilot monitoring had the ability infin and say you're too low.

44:10

Go around, you know what the limits are. The guy had requested that the FO come in before the flight and they watch the brief in that's given by a trainer on Guam because he said, it's a black hole in this mountains in the way. So that's not like they were totally complacent and the guy, those suggestions that they're captains fatigued and he's not happy with the company because he so tired and so on.

44:31

And you can kind of see that in the accident. When she get, when she Once you pass a bottom line, when you're outside the SOP, all bets are off. You don't know whether you're in a risk, assessed situation or not. Yeah. So what are they doing? Are they following the SAP for a non precision approach while they following the SAP for the closed today?

44:49

Because they now all assume it's working. Even though the first officer and the Fly engineer seem to be quite clear that it's not working. Situation where they didn't get away with. With something because the hill was in the way. But you're saying something so reliable. So useful, so successful.

45:09

As an ILS. Yeah, when it goes wrong, it's almost unbelievable. We've almost become too trustworthy. In it. It's like an unreliable speed situation. It's like the instrument is can't be wrong. The closely can't be wrong. I've been taught our whole life, trust the instruments, don't, you know, and this all carry on into what however, aviation develops in the future, even when ILS’s disappear, this same accident is still waiting to happen because How reliability is GPS?

45:34

Everyone's got a GPS receiver in there pocket and they know that works all the time. Yet, another Korean aircraft was shot down because GPS was interfered with on that day. So, everything is always fallible. And the more successful and useful and the more rely on these systems The more complacent so you can creep in, I guess.

45:56

Good points to finish on good points. Finisher But, I look forward to my next ILS. Yeah, me send out. Appreciate a bit more on the America behind it. Get staff. Yeah, thanks very much. Cool.

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Airline Pilot Technical Theory Adam Howey Airline Pilot Technical Theory Adam Howey

Circling

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00:00

Sam Adam Circling and approaches. Yeah. When was last time you did a circling approach? a traditional circling approach. Yeah. Because they might have evolved very recently along. No. I don't a few years. Yeah. I'd say the same quite a memorable space say yeah. Couple years. Okay. I think Pisa.

00:20

Yeah. Okay. Possibly. Yeah. I've definitely done one or two Pisa. I’ve done one in Dubrovnik as well. One the most memorable approach of my career. Is technically a Circling approach to Arrecife, Lanzarote Runway 21. Okay. Is that one of those this but it's not a traditional circling as such but because it's so offset it classes as a circling area.

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What is Circling

00:47

What is a circling approach? Well, I went straight to the manual. I came up with a visual manoeuvre following an instrument approach to a, a runway that is not suitable for a straight in approach. Normally, what do we do to make an approach to an airfield as an airline though?

01:06

Yes. And normally we would follow an instrument approach procedure. Yeah. The runway essentially is a straight in. It would be lined up with the inbound QDM of the only way, but at some airfields, that's just not possible, whether it's due to terrain. Yeah. Facilities. Wind direction on the day.

01:24

Obviously, can force you into a circling approach. Normally, we're basically flying down a beam in bound to something, which for an ILS. Is the threshold? The touchdown zone. Yes. Like a perfect piece of technology, you just fly straight down there. I'll take you straight down and the perfect angle to touch down on the runway.

01:46

Yep. A non-precision approach would be flying in-bound to a VOR or an NDB, which would be pretty close to the runway, if you're lucky. Yep. So you're saying that where you can't fly inbound to some kind of radio aid because there's terrain in the way there just isn't a radio facility.

02:10

Yeah cost wise you know there's no then you fly inbound to the airfield using some kind of instrument procedure. Yeah. But then you've got to do a visual manoeuvre to align yourself with the piece of tarmac that you want to land on. Exactly. It's almost like a visual circuit in a way you all.

02:28

Because is it a visual? Well, there is not a visual circuit but the pattern would look simple. You essentially using the instrument approach to get you to almost overhead the airport and then visually manoeuvring yeah to land in the direction you want to land in and there's like a traditional pattern that you see.

02:45

Yeah. But they might it might not look like that. No. Exactly the classic idea of a circling approach is that you make an ILS to a runway but the tail winds too strong for that runway. So you break just fly down wind and you're landing completely the opposite direction, using a visual manoeuvre.

03:03

Yeah, the majority of airports have intro approaches to every runway around my area but if someone's built an airport in the some stupid place, that's the way the pilot sees like nestled around some terrain. Yep. You can't have a straighten approach because you'd be flying through the hills if you're on because what angle do we normally fly and approach in vertically.

03:26

So typically a sort of three degree but there's an upper limit. Also 400 feet per nm. I think. Okay, he'll design limit. And I've always wanted to know more about how and who designs approaches to airfields and how they do it. There is no typical circling pattern. No and well there is one but in reality yeah it's not a visual circuit because we would I think everybody basically transport aircraft flies visual circuits of 1500 feet.

03:55

Correct. And this can be a lot lower. Yeah, definitely. Yeah. I mean you could be 500 feet or less by the time you roll out on the centre line, the same level intended landing runway. So yeah, so maybe let's talk about that traditional pattern just as listeners can visualise it.

04:10

So typically fly down the instrument approach. The ILS to let's call it a thousand feet. That's probably an average circling approach. So you go down to a thousand feet, a thousand feet, you would hope to be visual with the runway because you're gonna conduct the rest of the manoeuvre visually.

04:26

So visual with the airport, the airfield a thousand feet, let's be clear about that. So if you're not visual what your option well you'd have to go around because you can't carry out the circling. Anyway it's a visual manoeuvre. So to commence ther circling procedure to break off your instrument procedure.

04:43

You have to be visual. Yep. And there's obviously a couple of ways of define and what that means. Yeah and but you break clouds your visual, you would then turn to offset by 45 degrees. So thinking about which way you're circling, it might be prescribed on the chart as to circling to the south or to the west.

05:02

So you turn 45 degrees either left or right off the instrument approach track and then you generally time that for 30 seconds typically which would then put you out a sort of mile and a half maybe away from the runway and then you turn downwind to parallel the runway.

05:20

So like like you were in the visual circuit almost but a bit lower, a thousand feet and then when you get abeam, the threshold that you're gonna land on, I need the opposite end to the instrument approach. You start a sequence of timing and descend and configuration, which would bring you out in, almost like a continuous base and final turn onto the runway.

05:42

That's essentially what I'm trying to allow the listeners to visualise. What? Yeah, if you're not if you look at it from above the track, it would look like the let like a letter D. I suppose roughly? Yeah. Okay. Here I suppose. Yeah. a P if you circling left hand.

05:59

But yeah, it would look not far for general aviation circuit diagram. Yeah, downwind. And you have the like, but due to the altitude. You're lightly to fly a continuous turn from downwind during the basis. Finally. It's not gonna be like a long base leg because you're just not that wide. No.

06:17

So it is probably as complicated as as it sounds and there's a lot going on. What's the workload like workloads high and as we'll talk about later, one of the reasons quite often the workload is high is because people aren't expecting it. It's maybe been thrown at them last minute and they potentially weren't planning to do a circling.

06:40

They thought it was going to be the instrument approach to land on that runway all of a sudden the wind is shifted and it's now tailwind on that runway so out of limit. So you have to land from a circuit off the instrument approach and usually you're quite close to the airport at this stage.

06:54

So limited time to brief it which means the workload gets high. Even if briefed at the workload is still high, it's tracks. It's timings it's distances, it's configuration, you're close to the ground. It's not something we do very often. It's 12 years of flying. I reckon I've probably done five or six really one every couple of years.

07:11

Maybe if that and I've gone around from one out of my five. Where was that? That was into dubrovnik. That's why I remember. It's a well. So I only telling me so purely our own fault as to why we went around, I remember distinctly saying, you went around you hadn't.

07:26

Hadnt had your command that long? I don't think I and so. Okay, executed, you missed approach, fine, nothing wrong with what you did, really good decision. But now it's like, well, what did go wrong? Yeah, and if I repeat, what I just did, I might not just gonna end up executing another missed approach.

07:43

Yeah, because we went around because we were high. We turned on to final and we had four white lights on the, that one, the papi, definitely one of the fears when I think about circular approach, is like, I can execute the manoeuvre as per the manual. I can brief it.

07:55

I can overcome loads of the threats to this element of when I roll wings level on final or I get that first, look at the threshold on the base. Turn what if too low too high you know? Yeah. Why is that happen? This there's an element of approximation.

08:14

You haven't got many chances to get it right? No. You're moving to the area, you know. But just under 150 mile, an hour, just rewind it a bit then. So precision approach has got a vertical element to it. Yeah, a number is an approach doesn't have vertical guidance. Yeah, it's nice and fluffy to fly an ILS.

08:33

What? Firstly, it's what we do all the time? Yeah, I'd say 95 out of 100 approaches are probably an ILS but it's there. It's inherently like easy to fly. Yeah. It's sort of almost it says fly left fly right? Flyer fly down, the autopilot . It loves it. So, did you know that on a circling approach?

08:53

You're 25 times more likely to have an accident on a circling approach than a non-precision approach, and you're another eight times more likely than a precision approach. So, 32 times more so that makes sense. Yeah. Alright. Oh yeah, so when you look at the safety margins in terms of the statistics of accidents control, flying, terrain being probably the main one.

09:16

The ILS, is the safest non-precision approach. Is you're more like you have an accident but on a circling approach, you're highly more likely to have an accident. Yeah. Something that we're not used to high workload. A lot of few variables. Yeah, I was gonna say is a new one.

09:33

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Why Bother

This is like ambiguity to like, yeah, it's anything. Yeah, that contributes to this fact that you're more likely to have an accident on one of them, why would you ever do one then? Why bother. Yeah, I mean it well it might be the only way to get into an airport so the say, the tail winds on the instrument approach might be out outside of the aircraft limits.

09:55

You can't land on that runway because the tailwind, yeah, or subsequently, you're landing distance is not sufficient to land. So the only way to land at the airport is on the reciprocal runway, which maybe doesn't have an arm of approach, doesn't have an ILS, doesn't have a VOR approach.

10:10

It's literally it's got nothing. So the only option you've got is to circle to land from the other. And yeah, I guess there guys who guys, you know, and girls who design procedures they're going to give you every option to get into the area that they can. But I think it's worth those discussing just because it's technically within limits and it's technically doing.

10:32

Okay. Do you have to execute one but like you're saying the option is there for you, you might need to get on the ground. Yeah, and it might be the only you don't do anything outside of the SOPs. Although I do think some airlines have basically told the crews they're not to do certain approaches basically saying you can only do a circling approach if it's the only option available to you.

10:57

Yeah. Yeah. Any element of like instrument procedure guidance makes the approach safer. It's yeah. And that makes sense. And circling is is way sort of left up to your own? No you don't. You don't have any beams to fly down basically. Yeah. It's a bit of guesswork. Yeah. Of kind of tracks and distances timings.

11:18

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Circling vs Visual Approach

So tell me what's the difference and I really want to bring this up as a point. What's the difference between circular approach and a visual approach official approach is? Essentially, there are no minima. You are flying visually with reference, so reference to the ground. There's no sort of prescription as to where you'll be a certain point.

11:38

Whereas, a circling approach you actually are flying an instrument approach to get there. You have a minimum , there's a minimum associated with it. Yeah. And then you are following a prescribed sort of prescribed procedure from that. Minimum point is that I think to, to mitigate the threats associated with a circling approach.

11:59

Unlike other approaches, we fly, you need a higher level of knowledge and procedures where your knowledge and procedures about what you're doing. Yeah, about the design of it is more important than other approaches. People know that if you go out, whatever the limits are on your ILS or if you know you VOR, then you then you call a go-around.

12:21

But you don't necessarily understand the design of the procedure your flying , you need that increased knowledge of exactly what you're doing. Yeah, and one of the nuances or I think it's a trap is the association it has with a visual approach and the flight safety foundation did identify when they were looking into circling approaches and they've got a whole paper on issues identified, which you can find online.

12:51

One of their risks is that the ambiguity between the two. I think, if you understand the difference between the two, then you gain a long way to understand, what are circling approach really is. Yeah, so, just extremely back to basics when we fly airline aircraft. We're basically flying under instrument, flight rules, the whole time.

13:09

Yeah, regardless of what the weather's like. Yeah. And so, we need instrument, approaches to make approaches and even low visibility to approaches. I mean that we can basically take off and landing, pretty much any weather, and the design of the airspace, the instrument, approaches the departures, they're all designed to keep us clear of terrain.

13:30

Yeah. And traffic. Yeah, and now it's like a statement of the obvious but basically it's like we could fly with no windows in the flight deck. Yeah. Yeah. But when we do a circling an approach, it's a visual flight manoeuvre. Yeah, so we have to balance and the use of the instruments and the radio beacons that we might be using to get where we're going with.

13:53

Also just looking out the window. When we're doing a visual approach or there, we might choose to draw on some of the technology in the flight deck. The only thing stopping us from hitting the terrain is our decisions with regard to our flight path based on us. Looking at the window.

14:11

Yeah. Okay. Does that make sense? That makes sense. The reason you don't hit the hill on a visual approach is because you don't fly into the hill. It's same as a PPL flying VMC. How does he not hit the terrain? Well, he just can see the terrain . He doesn't hit the terrain, doesn't give you the aircraft on a circling approach.

14:27

You're using visual information, you're taking that into your brain through your eyeball, you ever have trainers, always say to them. The mark one eyeball and I never there, I was always like, I hate that phrase. They mean, like it's the first. Yeah. Or they're the first and the best design of the instrument that you have.

14:46

Okay. Fine. Yeah. Yeah. Use your mark one eyeball. Right. So you're using your eyeball and that together with other information navigation, information that you're taking in combined to make the circling approach, but there's a design criteria to the approach, which keeps you safe. Yes, we exceed the rules of this circling approach.

15:06

Then you could have controlled flight into terrain. So what sort of rules you talking about there then? What? Okay, so circling approach has an area. Like someone's got a, protractor from school. Yeah, they've stuck the needle part of the protractor into the threshold of the runway. Yeah. And they've drawn a circle around two ends of the runway, a little safe area.

15:29

Yeah, safe area and a lot of airports, you'll say, don't circle to the northwest or something. So it's not always safe all the way around the room way, but depending on the speed that you fly outside, aircraft is up to 180 knots cat D. Slightly higher. Then they've said this area is safe.

15:46

So was it 4.2 nautical miles for a cat? D? Aircraft around the threshold? Yeah, and then there's different like US is different. Well, let's come on to TERPS in a second, which is ridiculous. Right. But basically you have this kind of safe area and that in itself is a trap because I think a lot of pilots understand.

16:05

Okay. So there's a couple of miles which I'm safe. If I go outside of that, I'm not in the protected area but it's not just that, right? So there's a circular minima and they're different, right? Yeah. What they guarantee? On all instrument approaches include in a circling approach, okay, which is totally different from a visual approach is the obstacle clearance height.

16:26

Yeah, and it's only 394 feet when you circling in ICAO pans ops. Yeah, you might be downwind and you might be a thousand feet above the aerodrome level, but 394 feet below you. There could be a hill. Now, that's like really important to understand if you ask me because you've got to depart from your circular minima at some point and start to make your approach from the circular minimum down to the threshold of, the runway.

16:52

Yeah, now, all of this is in about 2.4 kilometres visibility. Yeah. So even though your visual, it doesn't have to to the visibility. So how many miles is that 2.4? Km is like a mile and a half and say, what your average decent size airport might have a two mile runway.

17:11

Like you see, might not even be able to see the whole runway . Yeah. Says, if you need to understand the visual requirements explicitly, right? And then you need to understand that this could be really, really challenging visual task for you to carry out to fly the aircraft and maintain this visual part of the many other.

17:31

Yep. So you could be just 394 feet above a hill, You could barely make out the airfield environment. So, that's, that's really tough now. Yeah, you have to stick to the design criteria and the rules and the SOPs associated with the circling approach is totally different to a visual approach.

17:49

A reason that I'm trying, I have a bit of a go about the two differences. Is that if you've got the two concepts mixed up in your head, at any point, you could find yourself, kind of, doing half of one and half. Yeah, yeah. And then you could have some control flight into terrain CFIT.

18:05

Yeah. Because your visual requirements, depending on the speed of the aircraft should be more. Akin to what you're used to as a VFR pilot. Which is that you have a vertical separation from cloud above you of like 1500ft or a thousand feet. Sorry. And that you have some kind of horizontal distance between you and cloud because you're travelling at speed and you don't know when cloud bases are going to creep down towards you.

18:30

And you don't know, you know, if you might turn left in a minute and you might fly over there, you fly here. So you need a big bubble of VFR space around you, right? So a visual approach you should have VMC criteria, right? So you can make those judgements about not hitting terrain okay on a circling approach.

18:50

If you just break cloud at the minima, the tail of your aircraft might be in cloud still. Yeah. And that's perfectly acceptable. That's allowable. Yeah, so there's there's a difference between visual approach and a circling approach and to me they're massive and they should not be mixed up. Yeah, whatsoever.

19:11

And I think some of these accidents that we might talk about. I just think in the back of their minds, they kind of remember their airfield from them a visual day and what they got away with on that day. Yeah, sure. Yeah. So you described some of the secrets of events that you would how you would position yourself and that's where I want to talk about the workload, which may even be kind of unique to the phase of flight, which is where using visual elements.

19:41

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Workload and Task Sharing

But you're also quite inside the flight as well and between the two of you. So you've got a lot of task sharing to manage. Yeah. So why don't you like pick up on some of that? Okay yet? So gonna have somebody flying the aircraft. Somebody pilot flying pilot not flying.

19:57

And the decision is to who's gonna land or who's gonna be the pilot flying for the landing could depend on which way you're circling. So that pilot on the inside, it's gonna have a much better view potentially of the runway and certainly around like a base turn. And my experience is that if you're not on the inside you don't see anything.

20:18

You wouldn't see anything. Yeah. Yeah. If you're on the outside of the approach, you'd really struggle so that that has to come into it. There's obviously monitoring of tracks distances timings configuration, there's a lot going on. It's really really big. It is quite busy and it's happening fast. You're you know, 180 knots.

20:35

You could only we probably that's the limit. But you potent manoeuvre, 394 feet above obstacles at 200 mile an hour. You can have tailwind probably but on the certainly on the yeah. So if you're on like it is, if it's three point, whatever miles for a cat C protected area, I mean you're gonna go from one side to the other.

20:55

Yeah. Very very quickly in. Not a lot of time. Yeah. You could have ground speeds of 220 to 30 knots which is 250 mile an hour. Yeah, pretty pretty fast. To be going above, you know, 390 feet above. Yeah, so yeah. It's it's a visual flight manoeuvre . Possibly in the worst weather, you can think of it.

21:14

So these are a few, the problems other ones that potentially catch people out is missed approach. So let's say you do lose visual contact with the runway at some point you're scudding along just beneath the cloud as you mentioned and for whatever reason you do lose visual contact with the runway you therefore have to or should execute a missed approach.

21:34

Well what sort of missed approach. Do you do you know you flew down the instrument approach to you're in a base turned and back towards the runway you've lost visual don't really want to fly back up the instrument approach. There might be the aircraft coming down it. So we are supposed to fly the missed approach from the instrument approach.

21:54

I the ILS that might be 180 degree turning face to face to. You wouldn't potentially do that or you might know you would know. That's but but people may negotiate. It's possible to negotiate with their traffic right to do something different because it might be counterintuitive to make a complete 180 degree turn.

22:13

But what I'm saying is it's just another layer of okay? Things to think about another element going back to what you said there. I mean the time to be working that out. Exactly. Yeah. I could have turned base. Exactly yeah. Yeah. Because by the time you've got the chart out and got a word in on the radio.

22:31

You could have hit the hills. Yeah. And let's pick up on something that I was saying again because I don't want I think this is a chance. Remove ambiguity. I mean, back in the days when JAR OPS came into the UK, so they started to harmonise the procedures across Europe before.

22:52

EASA, the manuals were full of should and could words and they went through them and just any sentence that said, that removed it. So you said if the cloud base is coming down a bit, you should go around. No, you must go-around, just 390 feet below.

23:07

You could be a hill. Yeah, you're gonna be extremely tempted to just, okay. Just just lower the nose as well. You should have the automatics in but just, you know, or hold on a few more seconds. This is just a puff of cloud, they were gonna get through, I don't want to throw away the whole approach just for that.

23:24

Yeah, so there's a massive trap there and the psychological effects there on you really powerful. You can visually see the runway. Yeah, I can see the runway and I can see the terrain below me. So why should I care about going through this little whisp of cloud? Yeah, is going to the brain is going to be screaming that you like don’t go around.

23:44

Yeah. Are you going to creep lower and lower and lower? So that's a real danger. Yeah. The other thing there is about the missed approach. So if there is any ambiguity in the flight deck, we always want to like take that out. Yeah. So hopefully back in the cruise while you were briefing.

23:58

All this. You could have discussed it with the FO. What would we do for the missed approach. Yep. And if there's something you're not sure about tell ATC beforehand. If we do a missed approach our plan is the next one said. Yeah, sure. So the guy on the inside is keeping his eye on the runway.

24:15

Now that's interesting because where do we normally look, we do normally look. There's the threshold. There's no way when I'm gonna start my timer but you need to also be projecting the flight path in front of you. Yeah I'm not gonna fly through cloud. Yeah you kind of make a safe descent towards the runway clear of cloud and terrain.

24:37

Yeah, definitely. And I don't think that's gonna motor skill that I have. Like always looking at. That's the threshold. That's yeah, you need to look ahead. I'm gonna fly over there and there's a bit of a hill there. And yeah, that's one that's another thing to consider. So somebody's busy doing that and the coordination between the two of you has to work kind of like clockwork.

24:54

Yeah. And you know I was wondering about training because it doesn't work very well in the sim in my opinion. No, the lots of trainers. Think about a certain approach in the sim. Yeah, it's not ideal because generally because the visual graphics in the sim, don't allow you that sort of range of view that you would normally get in the aircraft.

25:11

If you'd normally get a better, yeah, likewise, depending on the quality of the graphics in the yeah. Same, you know, it might not be quite as realistic or visuals. Yeah. Might not be quite as realistic as in the aircraft. So what about night in in real life more about night circling?

25:27

When you think of that? Yeah, I mean, we're allowed to do that. In fact, that works better in the sim, because you can pick out the lights on the wrong. Way easier. Some airlines on a totally say yeah. There's no night. Actually a night cycling. Yeah. So the pans ops design criteria for circling 2.4 kilometres.

25:46

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Challenging Weather

Yes, the minimum visibility to commence a circling approach, but any airline I've seen has five kilometres as a minimum. Yeah. But can I just say honestly, as a, as a captain, right now, if I was looking at an airfield with circling in 5k, I might rather be in the bar at the diversion app.

26:06

Yeah, honestly, this is what I was getting too earlier. It's like, you don't have to necessarily do the approach. No, I think circling even in, don't forget to and a half k. I, I think that's is 5k. Is it? What 5k is, is, did you say goldfish bowl earlier?

26:23

That's a trainers like phrase. I didn't know, I thought you said that, but I mean 5k is when you last make an approach in 5k like don't do very often and so, so adding to all of these layers of workload and stuff. You know, we're not doing certain approaches at Heathrow or Gatwick or just, you know, where it's flat, right?

26:42

You doing a circular approach at places like Pisa the Dubrovnik Genoa where there's terrain all around you. So many different hazards. The last thing you want to be doing, is up in your workload, by doing it in poor weather. So, you know, you could be in the bar and that's a bit of a might not be everyone's ideal, but I'm just saying you this painting a picture.

27:01

You could be in the bar at the destination. Yeah. Okay. So you could be circling in 5k. It's not just that. Yeah, diverted. Yeah, it's one of those things that you can never say what's the right answer until you're actually there on the day. And it's that balance between the safety and the commercial, Your passenger down the back is going to be pretty annoyed.

27:22

Seeing you in the bar, the diversion when they want to be on their holiday, do, I mean? And they weren't under something that he weighs on you and your decision making no, but they wouldn't understand like why couldn't we do the circling approach? You know, you're a profession you know, you paid a lot of money like and you're allowed to do it.

27:39

Why isn't something it's coming? Some of these accidents will look at is that in my opinion, although we've lectured you and I have both lectured meteorology, I still. Yeah, don't have like the best grasp. You know, the my the micro meteorological phenomena everywhere but it does seem to me that around terrain.

27:58

Yeah, the cloud like clings to it. Yeah, yeah. That's like a five-year-old explaining it but so often you're circling around the edge of this terrain. Yeah, that's right. Where these and I think some of these accidents that we'll look at have that feature. Yeah. Now, Arrecife 21 and I've had so many the different stories and in personal experiences about Arrecife.

28:20

But once upon a time, I did a diversion due to lack of visual reference during the circling approach there. So, went a Furerteventura , it’s the Canaries to in it's beautiful, right? And I get the cabin, crew watch in the flight deck, looks left, look right out the windows and when, oh, we've diverted have we?

28:40

And I was like, yeah, yes, it's not good. And I didn't pick up on it but she's being sarcastic, right? Yeah. Weather's bad, is it? And I was like, yeah, yeah. She went, oh, she looks out the window as if we just done it because today we get paid more if we divert or yeah.

28:56

Yeah. So yeah people don't understand. No and also I don't if you look out the window, the fuselage you might think I can see really far, but you might not be able to see the effort. Just it's totally different picture. Yeah, but my point is that there's no shame.

29:14

No, of course, not in say that. Basically, you know, it was taught to me, these sort of what is a red flag, you know. It could be all sorts of things, you know, the hairs on the back of your neck. Literally, you know, just when these things start adding up, I remember my last diversion was trying to get into Naples and it was just covered in thunderstorms, we couldn't even find a place to hold.

29:37

That wasn't like in a CB. Yeah, so we were like waiting for a bit before we maybe made an approach. Okay? Was and we started to take some vectors nothing? Okay, we're not gonna do that. I'm gonna tell the effort, like, what is he, you know, I'm gonna start questioning the FO.

29:53

Maybe maybe start a diversion but then the best red flag was the ATC came on and went. Hey, yeah, such and such and it was an airline that I don't respect very much. They just got in and I was like, okay, we're diverting. Yeah. You know, that was the red flag for me?

30:13

It was like, yeah, because often on these approaches, somebody gets in just before the crash. Yeah, yeah. Say the weather can't be that bad, but when I heard, oh, it's such and such an airline, I was like, yeah, yeah. That's if it went ahead of and, you know, Qantas just got in.

30:29

I'd be like, oh, okay, maybe it's terrible. But the pressure to, like, to accept these approaches and one thing when you find yourself, yeah, when you find yourself down there, they're in the basin. There were imagining in this terrain in this. Soup of low visibility mean doing, right?

30:47

You can do certainly approaches on CAVOK days as well. There are situations where the visibilities are not very good. You've got all the visual illusions, this tomato graphic illusion, the yeah, yeah, how close does train look in, love is all sorts of things happening to you. You should always have a plan B, right?

31:06

As an aviator, which normally is of go around, basically, you need to think it through maybe brief it, but that's the point, isn't it? You find yourself on one of these circling approaches and you might not have a plan B, if you've really screwed up because you like, how do I even get out here?

31:19

Which way, do I fly? How do I disorientation? You know, like the air traffic control everything. So, what you picking up on there? Yeah, the mr. Approach, hopefully would have been brief back in the cruise and maybe co-ordinate that with ATC, but the temptation not to go around because I go around, should be really easy, and straightforward.

31:38

But if any go around is gonna be hard, it's gonna be drawing a circling approach. It's gonna make you think I don't want to do this and you said that circling approaches your 25 25 times more likely to have than a non-precision non-precision approach, I kind of thought. Wow, that's because I didn't know that figure, but now that we've just spent 40 minutes talking about all the reasons why they're not dangerous, but why they we've not really gone.

32:02

See if anybody's listening, perhaps doesn't fly an airline aircraft. Like not even really talked about the nuances of like. Yeah, the timings you said, you set in an old-fashioned stopwatch to determine when to turn. How much bank do you based on wind and tailwind what she rated descend. Yeah, and then remember how do you judge that?

32:24

You've got any of this right? Yeah eyeball. Yeah. You line up on the runway does it look right? Am I around you? Yeah. And then you fly through a whisp of cloud and you're like oh come on. Like yeah, I can carry on now. Yeah, so certainly approaches are the least favourable for flight safety for pilots for air traffic control?

32:45

I imagine probably not that fun to them. Yeah because they want departure straight up the lane that you lovely just like on down front. Yeah, so no idea a busy airport but their designs say that there's an option to get you in terps, which I don't think is a direct initialism like t e r p.

33:03

S is the American for terminal approach. Yes. So their design criteria is even more insane. So, the the protected area, which is like an old-fashioned name for white spirit. That's what? Yeah, that's what I own there. Old men call like white spirits, got better. Yeah, but yeah, I think Americans think of it as a circling, how they design their circling procedures.

33:25

They're even more restrictive there. So if you don't have an understanding of the the diameter of the protected area, the rules say just reiterate it's not like a big safe play area. Yeah you got to get it right we in there see when you leave your minima to head towards the threshold to send was a threshold that's got to be done at the right point.

33:49

Say and with all these things that we've highlighted as the way you can go wrong. Fortunately there are quite a few so of accidents incidents that have come off circling approaches. Yeah, well they know you and I looked at the same one. There's plenty to look at out there.

34:06

They do all seem to have the same sort of theme though in that generally workload. Whether miscommunication they all have a sort of similar say a similar theme like a mismanage workflow. Yeah. Overloads a crash happens in bad weather. Okay, unfamiliarity, poor communication. Yeah. So, and which one was we talk about the China?

34:30

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Air China 129

Air China 129, Say, as always, this or caveat, we talk about accidents is not nice to talk about but it's always about improving, flight safety and learning from them. And, as with all accidents, there's never just one course, there's always the Swiss cheese, there's always numerous contributors.

34:48

So air China 129 was 2002. It was a Boeing, 767 attempting to land in Busan, South Korea. And I've literally written my notes here Swiss cheese, because there was a lot of there was a lot of holes throughout so it was poor weather. It was right on. In fact, it was below the circling minima that they should have been flying to this the one way, very when even sure what their own category.

35:16

Yeah, yeah. See. So this is the Swiss cheese as the first bit of Swiss cheese, so 767 the 767 manual. Apparently in a, you know, about me, you've learnt seven, six, you can be CAT C or CAT D depending on landing weight With the same, as the 321. Yeah, on this day, with their landing weight, they were CATC.

35:37

However, the 767 manual on the next line says for circling approach is it is to be considered as a cat D, because unfortunately, perhaps here, something shouldn't be mixed up, but it is you're landing fees. Usually based on your category of aircraft. Yeah, the airline wants you to be a lesser lesser category.

35:56

Usually between C and D obviously. So some of these aircraft are between the two but obviously, the manufacturers like for safety. Yeah, you're a cat D. Yeah. So they were asked a couple of times by the controllers to what category they were. They thought they were a cat sea aircraft.

36:12

And so, they were flights the CAT C, see minima, which was just below the cloud base. But actually, if they've been flying to the correct minima, which is the cat d minim, they would never have got visual at minimums. There was right? The minimum was the cloud basis actually below there.

36:26

So there's the first, you know, conf is the first hole in the Swiss cheese and protected area is less as well, this was a TERPS. This was terps something to do with the US military in South Korea. Probably yeah, I guess so. So that was one factor so whether not sure what minimum they were flying to.

36:50

But the classic, the absolute classic that we've talked about the late change of runway. So they were expecting runway 36 which was an instrument approach. They were expecting that all the way in and it was the last minute change to runway. 18, circling approach is said in the report, they had very little time to prepare and that that's classic if you haven't briefed ahead rushing another, what approach briefing?

37:14

That requires quite a bit thought, genuine question, then, oh, are there any options they could have had like having that high workload, sprung on them. Apart from, in hindsight, they could have briefed so you definitely could have briefed a certain approach. I don't know what their fuel state was but they could have taken holding pattern, perhaps, right in a couple laps of the hold just to just do the brick, complete the briefing because they were all them familiar.

37:38

I think I don't think any of them ever circled this airport before, right? But in my mind, if you're going to an airport and you're like well there's no less on that and what's on the other end and it's circling surely that's an alarm out of light. Oh yeah.

37:52

Well yeah. If yet possibly yet, definitely it certainly would be something I would consider I'd like to think I would consider but you know I I have had times where it might not been a circling. It might be something else. It was slightly more tricky but I haven't briefed it because I thought there's no chance and then all of a sudden it does get sprung, but it definitely happens all the time.

38:15

This happened. So workload was high and the classic sign that workloads high was in some of the radio calls I found, they were the approaching controller was handing them over to the tower frequency. But they didn't have the capacity to check in with the tower and then they missed a couple of calls and that's a classic sign of overload.

38:33

Their hearing had gone, they're kind of tunnelled into their brains prioritising. This prioritising what it wants to probably. Yeah, exactly themselves. Prior to kind of classic sign that they were, they were overloaded. And what else did you find interesting about it that regardless of whether their category cat?

38:51

See, they flew quite fast. Yes, they were to TERPS. They were supposed to be a 140 kts for a cat. C, and they, the flight data recorder had them between 150 and 160 knots, so kind of 20 knots fast going downwind. And then, as we said, you're highly likely to have a tail wind, which they really did have quite a tailwind.

39:13

Yeah, ground speed was really high. Yeah, they ended up downwind. They didn't turn, we would turn 45 degrees on the downwind of some reason. They didn't quite turn that much. So by the time they established on the downwind, like, they were already basically at the end. Yeah, of the runway.

39:32

Yeah, which adds to the workload? Yeah, greatly. And then one of the big contributors I read was that when the captain took control to commence the base turn and landing and he was on the outside as well. So nowhere near in the best, I'm not even sure that any of them really had the runway in sight,

39:51

You know for the whole approach I think there was times when they lost it and they gained it again but when the captain took control to make the base turn apparently it took him 40 seconds. Approximately 40 seconds to initiate that turn meaningfully through about 10. It's the point in three five zero degrees and they didn't go through north three, six zero degrees until 40 seconds after.

40:15

So you imagine it, you know, 200 and 200 knots ground speed. That's a lot of distance. Yeah, That they've covered you. Look at their diagram. They just fly straight.

40:52

Outside of the protected area in no time. Yeah. And for whatever reason, I think from the Korean accident report, they've overlaid the comms onto it. And you can see that they're not starting the turn and anywhere near inside the protected area. So then, as they're coming around the base, turn the first officer, definitely, lost sight of the runway though, they're all lost like the runway and the first officer called the missed.

41:14

Approach , but the captain didn't initiate it and about five seconds after that they they hit them out, hit the mountain. So my question to you would be if you've read this, why didn't the GPWS go off and tell them? They're about to hit mountain. That's all I kept thinking as well.

41:32

Yeah, I had to look it up so mode 2B. Yeah, I did not activate because unfortunately, the altitude that they're already at 700 feet with the speed that they were doing. Yeah meant that they didn't enter the, the envelope of the, the warning of the GPWS, or the caution, because they were fully configured for landing.

41:51

They yeah, a box out gear down. The rate of descent was sensible and their speed was sensible right until the last minute, where they had, I think 1800 feet per minute, but it still didn't have enough time to trigger. Yeah. So just to state the obvious, then obviously the GPWS stops some crashing into the ground.

42:09

But at some point, we have to land on the ground. Yeah. And we don't want it going off. Yeah. So the designers cleverly made these envelopes. Where if you slow down, and you've got the gear down and in the enhanced GPWS, they also build a basin around the runway.

42:25

Yep, that you can descend into but the basic modes are always there anyway and you're slow enough and you creep down enough then you can stop. Then there's even the G. So GPWS, why not go off? Which is really unfortunate because you would think it would go off. Yeah.

42:43

There's another trap of the circular approach, which is you fold the aircraft, into thinking that your landing. Yeah. Yeah, absolutely. Yeah. Absolutely. Other little bits I read about those system, the controllers had because it was a difficult airport with a lot of rain around the MSAW system, which I can't remember what that stands for some sort of warning system.

43:04

We're basically on the control on the air traffic, controller screens, it would flash if an aircraft was outside of the protected area and close to terrain. But is this why the controller kept asking them what their category was? So they could set it possibly. I don't know, because I think that tips is designing such a way that the control needs to know possible there categories, which is why they kept asking where's when we never ask?

43:30

Yeah, it could well be, but one of the kind of posts accident sort of review points, was that there should be some sort of warning rather than just a visual flashing light on their screen because to require 100% monitoring of an aircraft to see the visual flashing that it was, you know, exceeding, one of the parameters.

43:47

Whereas, if you had an oral sort of attention getter, that might have been something that could have saved them, potentially if the controllers had picked up on it sooner. But, you know, they weren't ready to blame. They they couldn't monitor the whole flight path. Interestedly. There were some survivors.

44:02

So yeah, I know I can't believe it including including the captain, I didn't know that Captain survived. Yeah. And those about 40 survivors. I think about quarter of the people on board to survived one of which was was the captain. I think they all had serious injuries. Yeah. And the captain was able to relay some of what happened to sort of layer on top of the flight recorders and cockpit voice recorder.

44:29

So it's all. So there's nothing wrong with the aircraft. The weather was within limits so it's a non-technical, it's a CRM. Yeah issue. Yeah, because of crash. Yeah, in terms of red flags again that they did say the I think the air first officer suggested going around at some point.

44:46

Yeah, he did. Yeah, I mean on any approach or any flight way or close to the ground, but especially a second bridge, somebody starts talking, like that, that should be a signal. Okay, we'll go around. We'll clear this up after. Yeah, totally, yeah. The other pilot might be wrong.

45:00

But let's go around and not waste time if this course. Yeah. So that could have saved them. Yeah, interesting and there's a really good picture that shows the crash site with the runway in the background. Yeah. So it shows because it was on the central line the centre line.

45:16

Yeah I think in two halves now we've just highlighted you know firstly from our own experience and secondly with evidence from the accident of the traps and pitfalls of of circling approaches, I think you put it. Well, it's a way to get into an airport possibly as a kind of last resort.

45:33

But it is an option. But there are some big inherent risks with doing it. Yeah. So I think now, people might never have to fly a certainly approach ever again. Yeah. Because these are RNAV visual approaches are cropping up. Yeah. But it seems to be led by the airlines because the airlines like I was kind of saying earlier don't really want you to be doing a certain approach.

45:55

But I mean, the airline I used to fly for most of

46:23

Most of our destinations in Greece. Yeah. Then the Greek islands they're all some kind of visual to them. So yeah, you know this wasn't an option to not do a certain approach. Anyway. The airlines are putting these visual on ever approaches into our databases in the FMS and into the charts.

46:44

Yeah. What's the differences? What's the reality of that? What's the reality is that rather than doing it on timings and tracks and distances, it's just a set of waypoints in the FMC that the aircraft will overfly with a vertical profile built into it as well. Yeah. It's got vertical and lateral guidance, and it throws you out on the centerline of the runway, that sort of 500 feet.

47:11

So, that one thing that I said earlier, which is this anxiety that, again, we're gonna do everything right. We're gonna brief it, but still want to turn final. It might be wrong. Yeah, that's taken away from. Yeah. Because as far as the aircraft and the GPS are reliable, it will put you in this exact space.

47:30

So I guess the workload element is much lower because you so you can dedicate much more of your attention to outside the flight deck, Although you're almost don't need to. Yeah, you're more confident in the system. So you could maybe accept. But just to be clear this is a visual manoeuvre.

47:51

Yes, nothing has changed there. You're just using the FMS to help you basically. Yes, when it's certainly approached, you're still responsible for making sure that you stay within the design criteria, Right And on a visual approach, you're still and on the second approach making sure that you're clear of weather.

48:07

Yeah, and terrain the whole time but the aircraft will fly, whatever the airline it would seem has programmed in for you, which means that your regardless of the wind, you're always going to be and the exact right point. I wonder that 25 times more. Controlled flight into terrain than a non position approach statistic.

48:26

I wonder how that varies with on RNAV visual approaches. Yeah, I guess time will tell because they're a fairly new. Yeah concept. They are relatively new but they're welcome. There is a not to people you know, here like like to fly visual. Yeah. Yeah. I like to do a certain approach.

48:43

There is the arguement that we're being de-skilled. Yeah. In the automation and on average GPS is just taking over and our actual raw, flying skills have been able to do a certain approach of being worn away. Yeah and that's one for a whole another the podcast. Yeah. That airline I used to fly for these to people used to say it's great.

49:02

Isn't she do visual approaches everywhere and it's not great, to be honest? Yeah, it's kind of fun for when it's going well. But every flight crews got a different idea as well about how to do it. Perhaps not circling approach but a visual approach. Yeah, cool. Well good. Let's, anybody finds himself on a circular approach.

49:21

Hopefully you won't have to do it sort of tracks And says, but if you do be aware of all the little traps that we've talked about and hopefully it will work out for you. Yeah good bye cheers bye.

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Landing Gear

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Use and Problems

00:00

Adam Sam Landing Gear. Yeah, we do without them planes have landed without landing gear before either by mistake or by you know, being forced into it once you're airborne instead of like no use whatsoever. No. It's used for well taxing, the first 10 seconds of flight and the last 10 seconds of flight.

00:25

Other than that, it's just a draggy weight to carry around. Yeah, yeah. And takes a lot of space. Yeah, it takes a lot of space, I researched that it typically weighs about 5% of the aircraft weight which is quite a lot really for something that is crucial to the operation but for the actual amount you use it, I think getting around the airport you could do it without landing gear, you could invent something.

00:50

Planes take off without landing gear but I reckon you can't land and stop the plane that'll just be crazy. Yeah. Yeah. Agreed and like on a 380, like the impacts on like the shock absorbs and stuff can be up to like 391 metric tons. precise stays like a. Yeah, well yeah, that is a phenomenal.

01:11

Like, who's landings there that? Well, yeah, I don't know, but I, but they take an a crazy amount of yeah punishment. I've done some landings which definitely punish the landing care. All the landing should be sponsored by a Messier Dowty as much as we credit ourselves with the skill of the land in actually, the landing gear is making all the difference.

01:35

Yeah, in ways like, absorbing the shock and dampening in that out and so on and just taking the hard landings. And yeah, the landing gears. They're like the hidden genius in the landing manoeuvre. Yeah. So complicated there, it seems like the aircraft manufacturers kind of be bothered with it and they sub it out to you basically.

01:56

All I know, is messier dowty, who is messier dowty Bugatti, make all of them. Yeah. They I read there like the major player and I think this one or two others that the people amount of landing gear manufacturing. But yet there's not many companies out there like they've nailed it. Yeah.

02:13

And I was like, well just use that, we'll just use that. Yeah, then is the tires. And there's not many tire manufacturers. I don't think. And they're also pretty reliable, but when I was little, I used to watch Thunderbirds. Yeah, any came back to me this week, there's an episode where they go calling international rescue and I'm pretty sure it's an airliner, okay?

02:33

And one of the gears doesn't come down, right? So Thunderbirds come along and they drive underneath the plane. Okay. They happen to have like something machine, that's ready to and the pilot balances the wing on there on the side. Like, it's all in my memory. Yeah, I seem to remember that episode.

02:54

I'm about, I've watched like a hundred times and I was about five, but could technically do something like that and then you wouldn't have to have landing gear. Yeah. But, you know, and so we talks about it's it's heavy. It takes up space. A could there be an alternative?

03:09

I would say, out of all the minor technical problems I've had in my career when airborne and when flying not so much on the ground, a lot of them do so you seem to occur around like the landing gear or the brakes or really? Because I knows we're steering or, you know, I wake up in cold sweats thinking about the gear not coming down when I've got not very half an hour of fuel there.

03:30

Yeah, yeah, what have you had? I've had that sort of scenario coming into Malaga on tight on fuel because we've been holding and it been busy and it wasn't anything major. I can't remember. It's the exact problem. It was sort of problem with the brakes, basically, with the braking system, too much to process before landing.

03:50

So we ended up going around. And I think Malaga it's quite a long procedure to the mist approach point and then quite a long way back in. So we didn't have much time to sort of figure out what was wrong with it and make it go and approach. It also not find in the end, but yeah, I don't know.

04:05

I seems to recall probably like a disproportionate amount of you seem to be around the landing gear as well, which kind of makes sense because it's a huge moving part. Yeah. Of the aircraft that comes up and down every time, you know, big hydraulic forces on it. So the guys in listening to this from Messier Dowty like yeah.

04:23

Exactly. I mean it's impossible engineering. Yeah yeah the I think the flexible hoses that carry the hydraulic fluid in almost any airline is going to be hydraulically actuated. Yeah. Majority of the force on the landing gear, to push it down and pull it back up. There's like these flexible hoses that run the hydraulic fluid or probably to the brakes as well.

04:45

Yeah. They usually the culprits of loss of hydraulic fluid because all the hydraulic lines in the aircraft, a brilliant. But then the ones they have to dangle down fold backer over here, get hit by stuff, they're in the free stream, air different temperatures. And yeah so they are planning gears.

05:02

Gonna be responsible for a lots of hydraulics, which in turn might affect the landing gear. In the braking, anybody has had gear, not down. We do actually, we do. Yeah. Yeah. That was underneath, wasn't it? Yeah. And so pretty, pretty bad did sound pretty bad. They were, but even the gravity gear didn't solve it.

05:21

Yeah. The red light is sort of, the alternate system didn't work initially. Eventually it did. But we had in my previous airline an aircraft that took off when they took off all hell. Broke loose, couldn't engage your pilot, loads of ecams, okay, no automatics, no flight directors, gear and safe, kind of indication.

05:44

Some something leading towards that flew around manually had a helicopter police, helicopter film the gear, like they thought the news wheel was probably at 90 degrees on the 320, okay? Anyway landed safely layer on. But can you guess what? Caused all that mayhem. No, not really positive the LGCIU.

06:07

Yeah, yeah. So I was thinking about gear and I was thinking about the mechanical structure of it and how clever it is. But then the LGCIU the weight on wheel sensors. Basically controls linear gear basically yeah. And but also the computer controls the landing. Again they computer that tells the rest of the aircraft, whether it's on the ground or in flight.

06:28

Yeah, yeah. Makes that distinction. Yeah. Feeds into pretty much everything you can think of. Yeah. Imagine that like, they took off and the aircraft thought it was still on the ground and throw everything out on an airbus. Yeah. Everything. Well and all it was was a link rod.

06:46

Gear was bent slightly, right? And on the airbus, there's 36 way on wheel sensors, right? And one wasn't aligned. And that's enough for the airbus to be like, we're on the ground and gears. Not say even though the other 35. Yeah, that's incredible. Yeah, so all those sensors and I, you can see the weight on wheel sensor on the news gear, like quite easily.

07:07

Yeah. All that mechanical linkage is asked to all fold up and go up and down, and up and down. And if the aircraft thinks it's on the ground versus in the air, that's not good. You could have a lot of the systems name function. Yeah. Theoretically, you can't put the gear up on the ground.

07:26

No. Is it thinks it's on the ground because the aircraft needs a grounds on the ground. So, yeah. A big part of the landing gear is the electrical signals to the rest of plane. I think. Yeah. Which is a big part of here. I haven't thought about that but yeah, of course.

07:39

So yeah, I did. I just think overall we did get a pretty disproportionate amount of technical issues centred around, not just the gear, but the brakes and hydraulics, all around that, I've had some birds stuck in the landing gear and they, yeah, tire burst or anything. You've had I never had Thai burgers late but or deflate no but you do hear of that that does happen.

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08:00

Large Landing Gear

We stop on our 330 fleet. You think of like bigger aircraft flying into like really well equipped airports but actually we're flying into a lot of old Russian runways in Cuba where you have to do 180 backtracks. Okay, on on 737s and 320s. It's dead by it, tight turn.

08:19

In fact, we drive out of stands and we turn the tiller wheel. And it's like a London, taxi cab, just like swings around. Yeah. But if you have multiple wheel bogies, if that's the right term, if you think about it, if you don't carry some forward momentum, yeah. You're scrubbing.

08:36

The tires? Yeah it's not one tire pivot in on it's axis, you're scrubbing. The tires literally you know like you're drifting in like some boy racer. Yeah, anyway, so we had instance where the tires would scrub at the 180 then the plane takes off and the wheel disintegrates on takeoff, right.

08:55

Okay. I know there's you know, famous like concorde for example accidents where the the tire debris and disintegration is caused they all crash. Yeah I think you know 380 whatever all big aircraft have video cameras, surveillance of landing gear help you taxi around and so on. I think also just to see how they're tracking along the ground and that you're not scrubbing them and stuff.

09:17

Yeah. See those. That the Antonov of yes. Like the answer of 225 or something. Right. I already got 32 wheels in 30 actual tires and I looked at a picture of like the layout, and it's just basically like a nose gear. And then the just two main gear with each with like 16 wheels on each side.

09:37

I mean, that's just keep adding more. They just keep adding more. Yeah, it's crazy the sort of layout of there, landing it. But that problem, you just described. Yeah, imagine that all 16 wheels just on one like bogey, one truck bogey. Yeah, I didn't really pay attention to any gear that much, but seven, four seven, as well as others, you know, has this incredible.

09:59

Got your main gear like kind of on the wingspar. Yeah. Then there's the two fuselage gear. Yeah. And then have you noticed that they're tilted? Yes. And the seven four. They're like vertical the, the main body one and then the wing one. Yeah, appar this say that they fit inside the aircraft when they fold up is that right?

10:22

All the tilted gears in the world it's because they have to tell to fit inside the fuselage because am I right thinking on the B767 they tilt forwards. Yeah. And the A350. They tilt forward. Yeah. And it's all about how they fit in fit and on the B777-300 of tail strike risk.

10:41

Yeah. When the pilots rotate, the rear gear gives them a little bump and that sounds ridiculous but it's held in a certain position so that it aids their rotations them off the runway rather than them continuing to pivot and scrape the tail. So that makes sense. That's interesting. Yeah, I didn't know.

11:01

It has an extra , what the piece is called, you know, that attaches those three or six tires yeah to keep it in a certain position which you won't see on the 777-200 and this and the concord that's where they were really worried about tail strike because of the, you know, angle of attack that it needed to fly at slow speed.

11:21

So it had a little wheel in the tail and which I didn't think you used. But in case it ever did tail strike that wheel would. It's not, you know, we all would take the impact rather than the tail strike. Yeah, of course, some aircraft won. The ones I've seen.

11:34

767 like a stick. This sticks out the back. Yes, tell you if you've done a tail strike, a concord just had a little wheel. Yeah. Yeah. So the gear is just like this crazy, jigsaw puzzle. Yeah it's a way. It's got to come down every time but also, it's got to nearly 200 miles an hour.

11:54

It's got to cushion. 200 tons or whatever. Yeah, yeah of whatever. Well you said whatever force it was. Yeah, well, 230, 400 tons on a 380. Yeah. But yeah, I mean, and I don't know if that's just a weight in the 380 but it could be more than that.

12:12

If it was a, I don't know where that figure is the actual impact. You know what the G, what the G would be. I imagine that's just the landing weight of a three. Like, I mean, the G like could be even bigger and at some point, it's somewhere. It's got to hit only one point of contact first, it's not going to just spread evenly overall, 22 wheels.

12:31

Oh yeah, I'm one tree. One wheel is gonna hit first which at which I guess the rest of the wheels will quickly. Follow soaking up wells, then start to until and then also that's where your LGCIU. Wait on wheel sensor comes in yes, you know, on the air bus when yeah.

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Weight on Wheels Sensor

12:48

And what's the same on and once it senses partial touchdown, it will deploy spoilers for example to help everything sit down. I guess. So you're less. In fact, there was an accident where they greased on a 320 greased on meaning like they just really smooth touchdown. They did it so well that the weight on wheel sensors didn't detect that they were on the ground so they didn't get the spoilers.

13:15

So they didn't get auto break. Okay. And they may have got some reverse depending on I guess, what? They've I'm just trying to think through the, the deceleration logic but basically if you don't have weight on wheels that the logic of the deceleration, that's all automatic. Yeah. Doesn't start to occur.

13:34

So they had a landing overrun, right? The first officer died because he hit his head on the map light, which is in the spa between the windshield and the side window. Yeah. So on newer, airbus it's built in, isn't it? Yeah. On older air but you could pull it out and remove it around and they changed it.

13:54

Oh wow, because of that incident. So if you don't get wait on wheels, which could be through, for one of a better term, your own fault, basically, by maybe some kind of unstable approach or landing in conditions, you shouldn't be. But whatever is occurred, you don't get your deceleration is on, but the LGCIU or the fact that you've touched down is a big part of that say these landing gear as well, help you sit down on the runway.

14:19

Because once one is on. Yeah, I mean, some pilots always land. One wheel down first is like bit of a bad habit. Yeah, I've noticed that in a previous airline that was definitely a technique. Was like, if you just float in a long a little bit, they just dip the wing.

14:33

One way to get a wheel on, and then obviously, you get all the extra spoilers deploy and it helps so dumps and sits down to all the left and sit down here. But if you're on a 747, you might not want to try that because you get a pod scrape or even a 737 maybe where a bit lower down, when the engines are slung quite like, yeah, it's interesting.

14:52

It's quite like, yeah, it's quite love interesting things. It's what hey, what about? Wait on wheels now? NASA invented that like everything? Yeah, because when they touch down on the mean, you hear Buzz, say contact light? Oh yeah, yeah. So they had like a have we touched down sensor.

15:07

Yeah, on the LEM. Yeah. Wow. Yeah. They always invent everything because thinking about like a typical day, where the landing gear. The first time we approach it will be on our would be on our walk around. So the pilot flying generally, we're going to make an external inspection of the aircraft.

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15:27

Walk Around

I always find the landing gear, the most interesting part, because the wheels are massive, and that's in a little airbus, they're huge like compared to a car tire, you know, they're they're incredible and they're rock. Solids 200 psi people always joke like you kick the tires but like, you hurt your foot, if you kick the tire, it's like get there, they're rock solid because they are thicker.

15:49

The idea is that once upon a time I don't know, on some US jet fighter, you kick the tires because you can't tell if it's deflated because the physical structure that's higher might maintain. See that's where it's supposed to do. Yeah. Yeah. They're like six times more inflated than a car tire.

16:06

Yeah. Yeah. They're filled with nitrogen. Actually. Yeah. So that it's, you know, it's more inert and all the temperature changes and stuff. I think less it. Go go to that. So so yeah we would you know, typically check the condition of the tire look for bold spots slightly, you mentioned earlier where you found anything in the tire.

16:26

Not found anything in the tire, but sometimes if you get like a bald spot, you see that like, webbing underneath like that white sort of webbing. That's generally the point of which I'd contacted an engineer for a worse. If people are always, I don't think there's anything ever written down as to when a wheel needs changing.

16:42

Well, there is but I mean for us as a pilot I don't ever been taught. That's that's a real change. That's not a oil change but they always say to me. That's fine. Yeah, basically yeah. He's a couple of grand for a tire. Yeah. Yeah. That lane like the cost of actually but they can change in like half an hour now.

17:02

Yeah, it's quite quick, pretty good. I live the aircraft up and not quite as quick as like formula one team. But like, they still pretty quick for the actual and they can do with passages on as well. I've I've had it done with passages on before as well. Maybe not.

17:15

Okay. Yeah. Maybe I can't remember. I always say to me that. Yeah. Because it will change. Yeah. Because they lift it any. A couple of centimeters off the ground. Sure. They have like a special like a formula aunty, right? Yeah slide. Just slides on and left it basically up.

17:30

Yeah. But they are like F1. I mean, they're like racing tires, because they, we're not, they're not designed for cornering. No, they don't have tread pattern, they just have a few couple of grooves in yeah. Yeah. But I've seen, you know, baggage tags and whatever FOD, that's lying around.

17:47

The apron can get so lodged in them space. You gotta look at stuff like that. Then obviously, we use some taxing around driving around on the ground. Generally, no problems there normally, but they, I mean, the. You can understand. Yeah. Yeah. They're not the grippiest thing.

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Nose Gear

18:06

They're not grippiest. You have to be really careful in snow and icy conditions especially generally. When you're in snowy and icy conditions, runways have been cleared quite well but taxiways tend to not been attended to quite as well. So yeah, to get really slow because you think about you've only got even a 320 or 321.

18:22

So 60 70 tons aircraft. You only got three small points of contact on the ground. So in IC conditions. Yeah. You got to take it really, really carefully? Yeah, a space. Like your car, your average cars, sort of weight and balance even though the passengers changing a car licence and now, I feel like in an aircraft, you know, you could be totally empty, you could be full.

18:43

Yeah, the distribution. And so, yeah, it's not designed for like manoeuvring. It's just it's just a means of getting tip into the in balance episode. Yeah, in that. So a nice wheel. It's just a seesaw and the middle gear is like the pivot and the seal but you just hope that it's resting on the nose gear, just slightly on the nose gear.

19:04

But what about the news? Gear extension earlier extension? Do you like a bit of light? Do you look at that? Oh yeah. Sometimes or sometimes like so when you're disembarking you get oh yeah, get ground stuff, come up and say, you nose gears extenders. So you think about disembarking an aircraft generally passage at the front start getting off first.

19:25

So then all of a sudden all you wait is at the back with passages waiting to get off and the aircraft is slow very, very slowly starting to tip up. So I've had occasions where a ground can remember has come up and said your nose gear like oleo is massively extended.

19:42

As in it's almost is limit and it's about to start lifting the nose. We'll off the ground sort of thing. We used to get a tail tip message, didn't reach like advised you when it disinvert the back first, it's something made sure the bags have come off the bottom of the cargo, hold to the back first and see the air bridge, you'll find like the passengers.

20:02

Again, off last, I've got a big jump. Yes, from the aircraft. Yeah, because it's gone up by like a few inches but relating that to the gear. Yeah, you've got the oleo like like any bike now, really has like suspension. The earlier is nitrogen and that's right, isn't it?

20:19

Not just the tire and then fluid as well? Hi. So those combined create their, like we said earlier, they're dampening and the shock absorption. Well, it's my understanding. Oh, I couldn't pay any numbers on it. That the nose gear is not really designed for as much impact as like the main gear and even when you see it, it's not as big structurally.

20:41

You know. Yeah. The tires are generally but it's generally a steering aid. You hear very occasionally of people having like a wheelbarrow nose wheel first. Oh yeah. Because that causes it happened once in a previous airline to somebody they yeah they had a bad landing and ended up it knows we all touched down first and yet, of course, all sorts of problems.

21:01

Definitely, not designed to land on the news gear. Say, somehow that happens, yeah, you can have news gear collapse and you can have any gear collapse but that's having a few times or to come up through the yeah, the floor of the aircraft. Yeah, I think it happened to Southwest not that many years ago.

21:17

I'll ask you trainer on our little aircraft, the 320 at the moment. We don't fly the nose gear on to the runway. No. But in bigger aircraft to touch down the main gear. And there's quite a few seconds that go by before the and the deceleration starts. Yeah. And that and the and your deceleration and your you're breaking on the main gear can push the nose gear down too fast.

21:42

Yes you want to maybe reduce the the smash of the nose gear like into the runway. Yeah not keep the nose up for aerodynamic deceleration which I think a long time ago on some aircraft they were supposed to keep the nose gear up to have some kind of air dynamic deceleration something like that.

22:01

But yeah, fly the nose gear on and bigger aircraft. Yeah, I gentle nose gear turns down so you flares, not even over until well on the smaller. Aircraft, any tend to just let it smash that here. We can get on with the So what are the talk about malfunctions there?

22:18

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Landing Gear Failures

You know, things that can go wrong with the nose gear and stuff? What are the problems? Have you heard of or either airborne or when you try and put the gear down? Or I mean your ultimate fear is the gear won't come down. So it's hydraulically actuated. So like all aircraft have some kind of backup system which is like gravity aided the gear should just fall down if you let it basically is is the way that it should work, is so heavy.

22:40

Yeah. So certainly on the airbus. It's like a gravity gear checklist. Yeah, essentially, just using the weight of the gear. It's not like that on every aircraft. Basically, the gravity should help it come down because the doors are kind of holding it up. Yeah. Or it's locked up in a way.

22:56

Yes. It's just a case of like, undoing. The pins basically that are holding. It has this hydraulically locked up above, 280 knots, or whatever, right? It could. Partially come down, the nose gear could come down, but be a 90 degrees, which is a specific thing that happened to a couple of airbus.

23:11

You could have a problem with one of the light bulbs. Yeah, it you for gears down and the gear is actually perfectly down. Yeah, we've talked about their weight on wheel sensors malfunctioning and causing problems. I think there is quite a lot. Yeah, I guess the point of making is there is quite a lot of things.

23:27

There's a lot of like moving parts and a lot of elements to the landing gear, but we practise, the landing gear gravity extension like quite yeah. Usually if company would like, hydraulic failure or something. Yeah, and all there's a whole checklist for it. It's pretty common sense, really? Yeah, but I've never done it.

23:44

But if you if you do that, you may or may not be able to retract it. So you can't just do that for a laugh. So if an aircraft lands with the landing gear doors open, it's really noticeable. Yes. Say just to state the obvious but just to make a point that the doors open, the gear comes down and then the doors closed.

24:07

Okay the doors on the on the seven four all big aircraft probably the same but they're they're like massive barn doors if you're gear doors are open. That's a massive amount of drag so they open and go away. Yeah. Also if you touch down with those down they might scrape the runway because they come down, come down quite low, but on air air, aircraft, a gravity or all, I guess, a gravity gear extension means that those doors open.

24:30

They then they don't fall away. Yes, there's no hydraulic assuming you've lost hydraulics but I did I did fly a seven five ones and we did a check flight and you'd all sort of stuff like depressurize, the aircraft and everything, but we did gravity extension, okay? But I think there's a maintenance way to, to reset.

24:46

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Landing Gear Drag

I don't know if we talked about it on the windshear podcast but you know, through the landing gear doors. If you're trying to recover from a windshear, obviously, you know assuming like you the microburst is pushing you towards the ground but you would think oh gosh got this super draggy year like surely getting the gear up would help my situation but the reason we don't do that is because as soon as you try and put the gear up, the first thing that's gonna happen if the doors are gonna come down these big barn doors, they're gonna come down to allow the gates come up which is gonna increase your, your weight, your drag basically.

25:18

Yeah. So that's interesting fact, there's always stuck with me is to you know, why we don't do that? Because yeah, I mean the gear doors are huge. Well that leads us on to like what like do you ever use the gear for a? Yeah other purpose. Yeah, I was gonna ask you.

25:32

Exactly. Same question and I did it on my last flight. Yeah. So the gear can be a really useful aid on approach particularly or even on takeoff. So let's take off briefly sometimes people leave the gear down if you've got hot brakes. So if you need line to get down for a bit longer and like just a cold air, just going over them at sort of 200, mile an hour cools them down quite quickly.

25:54

It's quite noisy. But yeah, definitely more often or not on approach. So if you've been sort of shortcut maybe by air traffic control or you've, maybe mismanaged your approach slightly and you're getting a little bit higher, a little bit fast or just generally high energy, then gear is your friend, put the gear down and everything.

26:10

Just sort of nicely comes back to you slows. The aircraft right down helps if you descent rate because it is so. So big and draggy. But yeah, it's a bit like a glide slope from a above. Yeah. Something where you're trying to quickly catch the profile or something and you might want to be, we normally put the gear down so normally I mean yeah sort of five miles to landing 2,000 feet, maybe 1500 2,000 feet.

26:36

So as late as possible because of the amount of drag on fuel burn but early enough to ensure the aircraft and a stable condition to land it interesting things, I think one is, if you don't put the gear up on takeoff, it's the first call after lift off, is from the PM was to climb.

26:55

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Gear Limitations

And then opposite road, you know, if I reckon tonight while I'm asleep, if you came in my room and went “positive, climb” I go. “Gear up”. Yeah, it's gonna be the number one motor function. However you've got the have to the after take-off checklist, but you can easily leave the gear down by mistake and start to exceed the speed limit.

27:18

You have the landing gear. Yes, even though it's incredibly noisy. Yeah. I think you'll start as you excited. You start to go? What is that noise? Yeah. And then you might go shit. The gear is down. Yeah. And suddenly throw it up, try to track it. But you actually going past the gear attract speed.

27:38

He said, how's that say, you can fly with the gear down up to 280 knots or something? Yeah, say on airbus? Yeah. If you want to retract it, how you've got to be like 50 knots flowers, 220 knots to retract the gear, why? Most of the doors? Yes, you rip the doors off.

27:54

If you go to well the motors that pull the gear up maybe is into the airflow? Yes, there was not powerful enough to do it. So you remember, when we did light aircraft training used to do a limitation operation indication? Yeah someone said flap when a single pilot you see when you want to move the flap or the gear.

28:12

Yeah. Then that's the little checklist. You'd run in your mind. Yeah. And we don't really do that on our fleet because we kind of do, but it's sort of built in on your speed. Tape is the flap. Yep. Limitation speeds. Yeah. But I stick with the limitation operating indication and I give a little placard next to the gear if I'm unsure.

28:33

Yeah. And then we will. Once took off from Manchester to do a couple of flight, four hours or something, and we had like a rudder ECAM or EICAS, I can't remember. And main maintenance said, we want you to come back into Manchester but we don't want you to land over-weight and you we can't dump fuel.

28:53

You don't want to dump your fuel on the peak district or anyway but on an unlike aircraft on the on A320. Yeah. So we flew around in the hold say to burn for quicker and put again. Yeah, of course. So then we want to go from the hole to final and we want everything to be nice and standard so we were like we'll put it back up but I just at the last second realise it sounds like I'm saving the day.

29:18

I happen to get something right on this day. I I I was like they were too fast for retraction. Yeah. Say yeah. Retraction speeds are quite limiting compared to L E. Yes, Is that right? No, Yeah, that's right. Yeah, with landing gear extended. So, yes, BLA. So landing gear operation.

29:40

So, like, with with the gear out, right? Sorry, and this is 280 on an Airbus and then VLE, the extension, the extension, which is 250 and then the retraction 220, he's 20. Yeah. So in emergency, we generally all the profile on the airbuses that we don't lower the gear because we get much higher to send and get down to breathable air quicker with the gear down but we'd have to slow down first.

30:05

So in order to get a gear down, exactly. And then that's gonna actually take longer than just then starting a descent and say gear attraction there you go like lots to talk about but also putting the gear down yeah just generally for burning more fuel or so you can use it to your advances sometimes.

30:24

Yeah you know it's a it's a, it's a draggy heavy. What about? And we've got a checklist for flights with landing gear, stuck down. Yeah. And it's not uncommon for a pilot to be asked for maintenance reasons, to fly position and aircraft not with passengers on, I wouldn't think.

30:40

But from A to B to like to, to lose for say that Messier. Dowty you can fix it. Yeah yeah exactly yeah. Maybe if it's have had a hard landing. In fact there was a news gear potentially a nose gear. First landing at Manchester and not in my airline, I think it was, it was in an airline, I'd flame four and they hadn't really reported it and then the aircraft took off and then they couldn't get the gear back up.

31:04

All right, so often the gears damage but it's okay because it's down. Yeah, maybe you can fly it anyway. Next. Try to move tractor. Yeah so you can get it to somewhere to be fixed with the gear down about landing gear pins. Yeah pins. So if aircraft are not gonna fly for a while, then engineers might install like lockout pins into the landing gear.

31:27

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Gear Pins

So basically which locks it just stops and retraction gear attractions but yeah you need to make sure the engineers have taken those out before you take off. Do you just? Yeah, I always check and I tell you why I always check because once there was one left in, yeah, on an engineering flight you're like an empty, an empty flight and it was first officer.

31:49

My first officer doing his walk around noticed the nose gear pin was still and it was extra good. That he noticed that because there is always a pin in the nose gear. Anyway, which is like the steering pin for the ground crew to steer on the pushback and what's that?

32:02

Then so he so that that was their pin, but there was two pins, you know I'm saying? Oh, I see. So for for the ground crew, when they're pushing the aircraft back with a tug, they used. Like a nose wheel steering pin to essentially. Well, what's the number? What was a disconnect?

32:25

Yeah, it's disconnect. The nose steering wheel steering so they can steer it further so that we can't try. And and time the. But if they left that in and we took off. Yeah. Well, if we manage to take off, well, we’d never taxy. Yeah, you won't be able to steer.

32:40

So when they walk off with the tug, they're also waving the pain in the pain. Passengers should be able to see that. Yeah, so I don't I always say man with pin you toe bar or something. Yeah, but a pin is quite important. Although we have a memo on the aircraft or tellers, but you're saying, there's also an engineering pin, which is there to prevent gear retraction.

33:01

But I, I thought it was, I think I would easily spot one on the mainland gear because you never see it there. But on the nose we gear, when you do the walk around, you quite often, see the ground cruise steering pin, which is look, look, similar to the lockout pins.

33:16

I now I'm like, very conscious and I do check, is there all greasy there if you want to get horrible? Yeah, if you get them out of the little locket, like a little wardrobe that they're in, yeah, they won't cover in grease, but I yeah, if you don't do it, you'll never do it.

33:28

Practise makes permanent, basic here. You'll never do it and then that'll be the day. You were it. Guess you should be too big deal. You try and retract the gear, and it won't come up because it's just mega embarrassment. Probably embarrassment more than actual. Yeah. If you've if you really want, you can get a car key car key fob.

33:48

When you call it, this says removed before flight. Yeah. Yeah. On your bag or whatever. Yeah. Hang like a bag tag here which would also be for like the air data stuff. But yeah, that brings up about and in a nasal steering and maybe that's part of landing gear.

34:04

I'm not sure but we can steer the aircraft without the nose wheel steering potentially with differential. Breaking differential. Thrusts, but we use the nose wheel. We can use the tiller or the rudder pedals to stay on the. I mean, if you, if nobody's got that far into aviation, that's what the pedals are.

34:18

They're their brakes, differential, like, you can break the right pedal, left pedal, and you can steer with that's what you use there. The pedals for that. Sounds pretty obvious, but hey, I'm flying a light aircraft. This is quite embarrassing. Not feeling a lot aircraft for a long time. Don't have noise of staying.

34:34

Today they have a castor that does turn, but you actually influence it by breaking on the main gear. Yeah, I think so. Right? Yeah. Because yeah, I've, there's never a tiller. Yeah, you got. So you would put in the turn in the rod and the rotor, but I spend so long that I forgot there isn't actually nosebleed in there.

34:55

It just saw pivots around like they're trolley wheel. Yeah, yeah, yeah. How am accidents and incidents? So many. I mean this year there's there's loads, we we obviously we've chosen one particular probably a fairly recent one to talk about but I mean, yeah, this this heat, there's loads and I remember what you videos of loads of it was like a virgin seven four landed at Gatwick a few years ago with it was missing.

35:23

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LOT Flight 16 Belly Landing

The left main gear didn't come down so it had like it's right main gear, the nose gear and those two fuselage gears so it kind of landed. Okay. And it never tips but it was it was like a bit. What it looks about wonky on this. Slight video. Remember watching that with my captain at the time.

35:42

He was on the 747 and he went or you'll be embarrassed by that because he saw bounces it. Oh, right. Okay. You obviously won't like this me this one. I'm sure the guy did an amazing job and yeah, a lot of these incidents or maybe accidents like Sioux City.

35:58

Yeah. The media of all turned up in advance. Yeah. Yeah. It has the pilots usually know. They've got a problem. Yeah. And then going to a very long troubles, a thing why? Which time all the media, tenants the runway. Yeah watch. Yeah. So yeah blue. Yes. 320 where the nose gear is at 90 degrees to the direction.

36:17

You should be. Yeah. Even the passengers on board is JetBlue. Such a fancy airline. We're watching the live footage of their landing. Yeah. From a helicopter, news, helicopter from their seats. That's like some kind of like weird, like inception. Like yeah, yeah. Watching yourself land from a television. But it's funny because pretty much all fleets apart from us.

36:40

You can this cameras on the gear and stuff say see would be able to see and probably turn them off if I was a captain. Yeah, no problem. You don't want to watch this but and the one we gonna talk about was the Lot. Polish airlines 767 Flight 16 back in 2011 november the first nearly 10 years.

37:01

Okay, basics of the flight is yeah. 767 flying from Newark in to Warsaw in Poland. So quite a long flight that piece of eight hours, probably nine hour flight time, I would have guessed. So I had a hydraulics problem after takeoff shortly after leaving New York and my first question to you, you know, for the benefit the listener would be so.

37:27

Okay. So they had this problem with hydraulics, after takeoff, not a major problem but they continue. Let's continue to go to carry on to wars or nine hours. Why as a pilot, would you do that? What I'm not saying that's what you would do, but why could a pilot?

37:41

Why could you potentially continue the whole flight? Well, the complication there is that they're going across the ocean into a, quite a remote situation with only two engines. So they have an e-tops extended, twin operations rules, which is like more stringent. So if they're just flying across the states, you know, from east coast to west coast or something, be even as even more of a different question.

38:04

So the fact that they went all the way over the Atlantic with only two out of the three hydraulic systems is a more interesting question. When you and I were at uni, I remember reading British Airways 747 took off. I think from New York wasn't then lost an engine and one of the four engines, but went all the way back to LHR.

38:26

It didn't make it heathrow, but nearly did, but it diverted in Ireland. So why? Yeah. And I think, yeah. And I think the Americans were a bit annoyed. Yeah. But the British were like, well it's totally within the ruleset. Yeah. By the Americans a bit more. Like obviously, you would just go back to the airport like, why they were, you know, what I mean?

38:45

Say that it made me think about that. I don't know what I do. I did used to fly 767 and over the ocean, but they didn't definitely have to return and I don't I'm not sure. They knew exactly the extent of the problem at the time. I do know.

39:02

There is what we talked about. It was a hydraulic flexible hose on the gear. Yeah. Which was like, a bit twisted over the years had just given and you know the thought process could have been. Well, this is only going to cause a problem on landing and we have to land somewhere.

39:19

So well, why not at home and spend the next hours. Next nine hours sort of prepping for it essentially. Yeah. I guess. So, what I'm saying is you can't well, you know, we went there, so we don't know the full extent, well if I, but it's not on unbelievable decision to carry on to warsaw.

39:38

So when you, when you've only So the idea of having three redundant systems, you know, is important, especially when you're flying over a remote region or over the ocean. So, knowingly, going over with only two. Although I confess, I don't know if it was a total loss of a hydraulic system at that stage.

39:58

But anyway, yeah. I don't know what we transfer the question. No, no. The question was just like, why could you continue? Well, I had a, yeah, I mean, I had a, I've had a total hydraulic loss and you just quite, you know, quite often thing. Well could divert, but it's only gonna be a problem on landing somewhere.

40:17

So sometimes you know there could be arguement for carrying on to also. Okay, so then they got to wars or eventually attempted an approach and that was when they really knew the extent of their of the problem of the hydraulics failure because the gear wouldn't come down. Well, it can get the gear down to think not to say that you got that wrong, but they knew it would have to be like an alternate gear extension.

40:48

Okay. Okay. Yes, they lost the heavy system, okay? Yeah. Fair enough. Yeah. But they, or they lost part of their system that uses but the alternate gear system that they were expecting to work on final approach didn't work. Yeah. So then this is yeah. Why is that related? You know.

41:05

Yeah, there's they they must have done a lot of think ahead. So okay we're gonna and we've lost a hydraulic system. What are the consequences for the flight? You know the cruise the approach? The land in the rollout? Yeah. And one of them was okay, the gear won't come down but we use what we call gravity.

41:24

Gear, extension. Alternate, great extension or something. On the 76 electric motor isn't it? Like is the a lot of the lock is. Yes, so that's kind of important to the story. So on our aircraft, it doesn't work like this. Once you open the hydraulic lock, the gear falls down.

41:37

Yeah. On the 767. There is an electric lock. Yeah, which has to be moved. Yeah and it's really important that that lot can be moved. So it's attached to like a battery bus that would function even in. Basically a total electrical failure you would still have access to that to get the gear down.

41:56

So no problem, but that didn't work, the alternate gear. So they ended up doing a go around and then exactly as you described, they held them for an hour trying to figure out like, what really has gone wrong here by which point everybody is alerted to the fact that this aircraft come in fact, I've even sure that I remember hearing it on the news before it actually left before the aircraft had actually landed.

42:21

I'm sure I got like a news update or something saying, there's a lot 767 with a landing gear about to make an emergency landing in Warsaw, so they evacuate the airport. I think close all the roads around the airport, setting up two fighter jets to go and have a look, you know, trying to get a look at the lots of the pilots near the gears not down, like it can hear it?

42:44

Yeah. But I guess they're looking for light is it's kind of stuck half down like any sort of information. And if you've listened to the oxygen episode, like we know how close like fighter jets will. Yeah, and probably Polish fighting yet. They're probably, like, stick hand out around out of wiggle.

43:01

Like, yeah, trying it down. So why jets site kind of went up to have a look at it but imagine you've done your 11 hours over the ocean. Probably even had like nice sleep controlled rest. Yeah. You just think you're gonna be filling in a minor ASR about a hydraulic loss or something and a minor report about a holly a hydraulic loss but that moment the gear didn't come down on your backup option.

43:27

You then started. I think that would have been shock and start all moment of like what have we misunderstood definitely how is that related? The gear should have come down. So every aircraft you're looking at has a way to put the gear down but there's always a backup option which basically means it will always come down.

43:45

Yeah, right. Yeah, even if you've lost all your fuel, all your hydraulic fluid, or your electrical systems, the gear is it's like him. So the the risks involved in a gear up, landing are really high, so it's like a system that has to the risk of it. Not coming down has to be like as close to zero as possible but there is a checklist for a gear up landing.

44:07

But I see that as more of like a team building exercise to distract you from. Yeah, your imminent catastrophic actually it's like the bomb on board checklist. I'm like this is just to distract you while. Yes, you don't sit and think about what's actually gonna happen. Yeah, I don't think it's of any use but that's not true.

44:28

I mean, partial gear extension and stuff, like very survivable but there's some bad examples of them as well. So just to be clear about this. There's no way in anybody's mind that the gear is not going to come down. And then all of a sudden, it doesn't come down now and we always talk about Swiss cheese and you know, holes in Swiss cheese lining up.

44:48

Yeah, you know, here you go. So there was a hydraulic failure, but that shouldn't mean an accident. It's funny. The Swiss cheese just one because there's not that many layers, but the two holes are like tiny, but they just perfectly lined up like, yeah, you know, it's not a matte, it's not lots of layers of Swiss cheese.

45:08

It's only really two kind of layers, but they're just like perfectly aligned. So we know about one hole so it's gonna hydrate failure, no big deal. Yeah. Say the pilots have gone to go into a whole troubleshoot and and come to the realisation that the gear is not gonna come down.

45:23

So want to perform the gear up landing checklist, which will tell them to do with this little fuel as possible. Yeah. Because obviously you then start to land on the structure of the aircraft and the only thing between you and the runway then is the skin of the aircraft and the fuel tanks are full of fuel.

45:40

Yeah. Say you don't really want fuel spilling out while you're sliding down the road. Am I right in thinking that whilst this was going on while they're holding for an hour that the pole? They're like also airport the poles like put some special stuff on the wrong way. Yeah, and they can do that everywhere.

45:56

They phone their own way, and I think it actually works as well to prevent fire. I think it's not just like another team building like, didn't worry like that. We've found the wrong way. Like you become party. Yeah. No. It's actually a fire retardant. You know idea? Yeah. I have a lot of fame, ready.

46:15

I'm just gonna say same around my favourite runway. I guess the managed to fame, probably like the most important bits of it. Yeah. And so yeah, they're gonna have to do a gear up landing. The one they, there's never thought they'd have today exposed to, in the back of the mind.

46:32

They got me thinking, how is this possible? But I guess they, in the end just thing, it's just not our day. Yeah, and the runway's phone, the airports have accurated, the roads are evacuated, there's not much fuel left in the tanks. The cabin crew have got time to prepare for it, the pilots the ground.

46:50

There's some what they made services are probably be thinking ahead. Yeah. It's almost, you know, if it planned. Yeah, yeah, yeah. It's like what you see, almost became. It's like we're gonna crash. Yeah, everyone ready? Yeah. Yeah. We've got an hour to sort it out. Yeah. Yeah. How long they had, which they're lucky because they continued all the way to Warsaw.

47:12

Yeah, and still had a bit of fuel to sort of stuff out. So what happens next? Well, by all accounts, like they kept in and the crew did like an amazing job of like this. Perfect gear up, landing hundred percent, everybody, survived minor. If any injuries everybody walks away basis.

47:33

How to evacuate as a matter of proportion? Evacuating any aircraft? Let laying with 300 people on? Yeah, you might get a death because you throw in all sorts of different people down. Slides in a panic. Yeah, of course. But no, that was fine. One of the engines caught fire but don't worry the fire service were there.

47:52

So please put it out straight away. Initially like the guys were like hailed his heroes and I mean they did do an amazing job but there was like a little tinged here to the heroism discovered later on which was the reason why the alternate gear didn't work which was the circuit breaker.

48:12

Yeah. On the battery bus that has a couple of important things connected to, yeah. That circuit breaker was pulled that circuit breaker was popped pulled up up to you. Exactly. Yeah. That circuit breaker was out. Yes, which means that it's like you've unplugged those systems. Yeah. From the mains basically.

48:33

Yeah. And I don't think we ever really know why it was out whether it popped, or whether there was a, there was a suggestion that because it was next to one of the crew bags that a bag, you know, being slated into place had like popped it. I pulled it out by accident.

48:50

Yeah. So I think my understand is more than like a suggestion. It's like that is what happened, that's what happened. So they know for a fact that it there was no electrical failures that cause that circuit breaker to pop. So, in the flight deck, you've got a panel of circuit breakers and when their passengers come in to have a look around and they look at all the switches, they often look at the circuit breakers and go, oh my god, all the buttons.

49:14

How do you know what what they all do? They're not buttons. It's just like a fuse box at home, right? Yeah. And I can't remember about the seven six not but on our aircraft if one of them pops the ecamel tell you. Yes. And if it's, if it is a monitored, what colour is a monitor, lizard green.

49:35

Yeah. So it's a green circuit breaker. It means it's monitored. Yeah. It's music. E-cam will tell you, if one of them spots, any will tell you, like, look on this row and then you can see that that it's popped. And I guess the seven six doesn't have that. No, but yeah, when I feel, I was a first officer and right by your flight back, basically, and where you sort of walk into the sea.

49:58

Okay, there's a little wall of circuit breakers. Some of the most important circuit breakers. Yeah. That never probably the most important ones. So, somebody designed the aircraft and somebody decided to put them there, yeah, Boeing sold and optional extra which was a cover for that that particular panel, right?

50:20

Say that you couldn't accidentally knock them because it happened on loads of different aircraft already. Before this accident, these guys were just unlucky that it happened as well as failure. And essentially, they lost both mechanisms of low in the gear, That, that circuit breaker was kind of like damaged.

50:40

Like it'd been knocked. I probably more than once in its lifetime, Right? Right Bear. In mind, that while they're troubleshooting they're on the radio to, you know, maintenance operations. Yeah. And they gave them five different like maintenance kind of fixers. This is definitely going to work and including a circuit breaker for the alternate gear extension, Right?

51:05

Which is called like F1 or something. Then and there were like, all you got to do, is reset that. Yeah. And I think the FO did it like seven times. Wow. So, bear in mind that the flight crew at some point, probably the first officer is knocked, this circuit breaker because it, it was, would have been in before takeoff.

51:24

Yep, right. But the whole of lot airlines possibly even going on the end of the radio, couldn't figure out that it was that yeah. Boeing knew about this problem, but hadn't had designed the aircraft that way. Then knew about the problem, then some then offered a fix to people, but didn't enforce it and maybe even the regulators knew so were the pilots heroes as the media might say or you suggested.

51:52

Yeah. But where they like these antiheroes when you found out they were actually caused the, the last layer of the Swiss cheese. Well, no, because not one person on that day. No, came up with the idea of. Why have you just not here with your flight bag like? Yeah, right.

52:08

But imagine that writing off an aircraft in a belly up, land in down a runway and it's a tiny little circuit breaker. It was characters as a whole loss was there. Like, yeah, they wrote it off right now but a Polish prime minister rightly gave them like oh yeah, awards and they are and they are heroes and massively.

52:26

If you can understand that you might be that first officer one day. Yeah. And he does the most stupid thing in hindsight. Yeah. But does everything else according to their training and procedures? Absolutely perfectly and goes beyond then. Yeah, then you'll understand like the nature of the nature of aircraft accidents.

52:46

And when I started flying, the seven six seven. That's the first thing they told me. Yeah, don't knock that with. You fly back because you remember the lot thing and I was like, oh, right? Yeah, so I'm not gonna make that mistake. No thanks to those guys. Those guys you made who paid not the ultimate price, but managed to show how good they're their skills are.

53:08

Yeah, again like more evidence. We say, every time of just learning we learn so much from other aircraft accidents but we like to learn proactively from you know, occurrences and incidents say yep. Boeing should have put out a thing. Should have put a sticker in front of the FA saying, did you just knock that when you guy in the seat, just have a check or something like should even be on like the gear checklist?

53:30

Like the well, they get in the QRH like check CB I'm sure I'm sure is now this podcast isn't about circuit breakers but do you if you have a failure? Yeah, and you run three the ecam. You might do a bit of thinking outside the box, you might consult the manuals called main troll.

53:50

Do you personally are in your checklist, think? I'll just turn around and check the circuit breaker probably not. By not religiously. No. Say yeah we're not expected to you know we don't have I had a little fire basically in the flight deck and the on the checklist it says isolate faulty equipment.

54:10

Yeah. So as I wears the with, how do I isolate the printer? Yeah, and I went through the every row and then, it says PTR SPY, which I guess means still to this day I guess it means printer supply. Yeah, I was like well I'll pull that. Then try that but we don't have a list of the CBs and we're not that's not part of our chatlist to check them so the landing gear and was functioning perfectly that day.

54:37

Yeah, I guess the crew demonstrated how important they're landing gear is yeah. And and how you can pull off it and they're landing without the gear. Yeah, but in hindsight was preventable. Yeah, gets really interesting. I think that's it. Cool, yes. Bye.

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Altimetry

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Transcript Start

00:03

Sam, Adam, Altimetry. What do you know? Well, I feel like I know a lot. Why? Because it's in our everyday life, okay, but then I also feel like I don't know as much as I should. And when it gets very technical, I don't really, you know, this just things that are more clear to understand it.

00:22

Yeah. Maybe. But obviously, then this is not so much about the technical side of it that we're gonna talk about. Do you think the scope of this is big or? Yeah? I think so. I think you could go on a lot of tangents with our altimetry and altimetres, okay?

00:36

It kind of touches on instrumentation and pressure. Where should we stop? I thought maybe the different types of altimeter. Okay. I thought of three that we use commercially three different types. Can you think of any more? I'd say if I can think of three, but I was thinking the barometric altimeter, obviously, the GPS altimeter, which we don't really use, but is there and then the radio altimeter, yeah, as well.

01:04

And maybe just explaining the differences and how we would use them differently and what they used for. Should we talk about? Pressure altimetry barometric? Yeah, sounds good. It might be the main source of altimetry. Yeah that's generally what we use primarily? Listen to. But what is your altitude?

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Altitude

01:24

Yeah. What does that mean? Well, it is obviously your height above sea level based on standard atmospheric pressure. I feel like if mixed of a few things that yes probably I'm sure when I was doing my research I read some Latin like definition of oh yeah I'll team metre or I'll really yeah but I'm interested.

01:51

I can't remember. Yeah. Sorry, well I mean I think you can distil this to the basics which is do we ever really know what our altitude is? Well, yes, sort of. Okay, this is, yeah, with the radio altimeter. Okay, good point, but not so much with the barometric. I agree.

02:15

What do we want to know our altitude with reference to? Yeah, and the core of it being what is an instrument in the cockpit. What is it? Really telling you? Yeah. Okay. And after staring at it for 30 years or 50 years or how long you career might be, what does your brain think?

02:39

It's telling you do we need to always be aware of the limitations of everything that instrumentation the aircraft, especially these things that were staring at. Yeah, all day, every day. Yeah, because I feel like after thinking long and hard about altimeters I've realised. It's more of a concept than like a.

03:02

Yeah yeah and an absolute thing. Yeah, I agree. So you like to tell everybody, were at 3,000 feet feel so secure. It's like I got three zero zero. Yeah. But where am I? Really? How? How high yeah. What exactly is my height above? Well, let me level the ground.

03:21

Yeah. Let's separate those terms first. Because you said, I said, what's altimetry? And you said something about and use the word height? Yes. So that's distinct from the word altitude. Yeah. So what is height? So height is your distance above said objects to the ground easily whereas altitude going.

03:53

You can say something when you learn the two uses of the words in aviation yeah. High is your distance above the runway and altitude is your distance above sea level. Yeah, your flight level is your distance above a datum, 1013hpa, here. So say we should make sure we use the word height and altitude.

04:17

Which I hear people use the word high incorrectly all the time. And since I haven't done any general aviation for a long time, I've not set the QFE no, for a very long time. No me neither. I used to love it. They because when you touch down it reads zero at the threshold.

04:33

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Pressure Altimetry

Yeah. And when I was in the circuit I just flew out a thousand feet, I didn't have to fly it. Yeah, 1270 feet. Exactly. So I missed the QFE. So let's talk about barometric altimeters on our aircraft on the, on the airbus. So what have we got in the flight deck barometrically?

04:52

Well, I've got a PFD. Yeah, my colleagues got a separate, PFD primary, flight display, yep. With this most amazing altimeter, which I take for granted. The display is what I'm referring to, yeah. Because the three-pointer style altimeter, the drum barrel style and so on have been attributed to accidents by pilots misreading, miss reading them.

05:19

Yeah. Various and so they like to use combinations of those but the one that we look at is so clear. Yeah. And the way they've integrated, which will come on to radio altimetry on top of. Yeah, pressure altimetry. Yeah, is really good. And we also have standby instruments in the flight deck, which may be an older fashioned style of display display.

05:43

But like a lot of things on the aircraft, we have three separate sources. Yes, that's important of air data. Yes, which we can kind of move around the displays, but you should have in normal situation, three, separate displays of three distinct separate air data. And if one of them is unserviceable, you could turn that one off and still have three displays, but from two sources, right?

06:12

Yep. So we like three things for redundancy and complex. Yeah, airliners okay so we're wherever Manchester Leeds Heathrow takeoff on wherever just the places we've just been with, we would would depart on the local QNH here for that airport, which would obviously. So they are reading on the altimeter would be the heights, the elevation, essentially of that airport above sea level.

06:43

So yeah, 200 feet, 250 feet, wherever 600 is 600 leads. Usually, yeah, LHR is what to 200? Just under 200. I think mean sea level, that's what they say mean. Let's sea varies in like I don't know, the tide maybe anyway. Well yeah, that's a whole, that's a whole podcasting itself if you want to fly really close to the ground.

07:06

Yeah, your best staying away from pressure, altimetry. Yeah. So you don't have to worry whether the sea is gone up or down a few, a few feet that day. But, yeah. So I've got a really good story about flying very close to the ground, which I the, you know, about, but we'll come on to that later on because that's exciting.

07:22

I hope it's not like me or you doing there and everything. Okay and so he throws a couple hundred feet leads, for example, sits on a hill leads Bradford says 600 feet. So when you're sat in your aircraft, doing your pre-flight checks and you have a look at your altimeter, it should say, and 600 feet in leeds.

07:42

Yeah, exactly. Yeah, okay. Providing you set the QNH it's correctly. So then you take off and if you had just all flying around the circuit leeds down initially climbing out on the standard instrument departure, you'd stay on that QNH until you reached the transition level which I hate the definition of transition level and transitional altitude.

08:03

Yes, it messes with my brain but luckily for me practically you don't need to really know where it is. No, when you're under radar control. No, exactly. And the idea being of that that once you've passed through that everybody sets standard pressure which is 1013 millibars. Hmm.

08:22

So that if you take enough from Heathrow on a QNH of say 1 0 0 3 and somebody's taken off from Manchester on a QNH of 1 0 0 1 and you're converging to each other eventually once you've gone through the transition level everybody's on 1013. So we've all got the exact same.

08:39

Yeah, pressure setting because when we take off from Leeds and there's the peak district around or the Yorkshire Dales, and then we want to know what our altitude or high is reference to the terrain. Yeah. Yeah. But once we're away from the terrain so they'll set the transition level.

08:58

Well above any terrain for that country? Yeah. Because I think in the states is like 10,000, maybe yeah. Yeah. Some places are really high. The UK is different to be a six usually between six and seven thousand feet normally. So once we're above well above terrain, it doesn't really matter how close to the train.

09:16

We are as accurately as it matters. How close we are to other craft. Exactly. We need to know what our altitude is with reference to their aircraft and like you're saying if there's high pressure down in London and slightly lower pressure up, north it leads, then as you travel from one place to the other, you're going to be on different QNHs , exactly.

09:35

It's just not going to work. So you all need to be on the same pressure setting. Yeah. So that so that we're all nice and separated. Yes. From each other. Not from the terrain. No from each other. Exactly. And we usually use a thousand foot separation and this is it.

09:52

It's kind of emphasises the importance of making sure that you have your QNH set, but also it also links into every as long as everybody's on the same. Then you're always going to have a thousand foot separation if somebody's unless you're altimeters not working. Correct. Yeah. That's yeah. Absolutely.

10:10

So a thousand foot separation is our RVSM? Yes which isn't been around forever. No, I think 2002 and Europe led the way of RVSM. Yeah, and be. Yeah. 2,000. Yeah. 2,000 feet was separation version and it's doubled amount of aircraft. You can fit in a box of airspace essentially.

10:32

Yeah so they eventually did it over the Atlantic as well so again went from 2000 foot separation to 1,000 foot separation and I learnt that something I didn't know which is that during the implementation of that. They, they being the regulatory bodies, wanted to know how accurate, actually, everybody was keeping their altitude, right?

10:55

Because now are only a thousand foot separation. So they wanted some kind of check on it, right? So did you know that they actually geometrically measure our altitude in Europe in that busy busy part of airspace with something called height measuring units. Okay. So they get the ping off the transponder like how GPS works using the time.

11:21

It takes to ping that aircraft to a certain station and another station on another station. I think they except they triangulate it. So they work out your geometric altitude. Nothing to do with your pressure reading, nothing at all, and they compare it to what you're supposed to be flying, right?

11:38

And they actually hone in on certain airframes that have bad altitude, keeping? Okay. And then they all contact the company and say, you know, G-BBBA. Yeah, is always flying 200 feet low, okay, that's interesting. And they can also track certain manufacturers or so aircraft types and say that aircraft.

12:00

They're not keeping initially or not. And they're always 100 feet low and you can see these graphs of where they've intervened and then the altitude keeping's got better. So vertical separation is so important to safety that they needed to introduce RVSM. But they were so worried about altitude, keeping that they, I'd ever realised that they actually monitor our geometric altitude to see if your aircraft, your company, your manufacturer has good alternatory.

12:34

That's really interesting. I didn't know that. I'd not really bother. Yeah, I didn't know that, you know, we could go on just loads. So you could talk about the they downsides of thousand foot separation. In terms of how busy and TCAS or did you look into überlingen air crash for this?

12:54

I didn't but I know. Yeah, I I was tempted to but I didn't either. So I have to look at that another time but that is that maybe that's another podcast. Yeah, I think so. Yeah, be a good one. So TCAS is a system that helps us keep vertical separation when things have gone wrong.

13:10

Basically? That's the same busy piece of airspace that where they first introduce RVSM. Yeah. But I just like exploring the idea of like, what you say, basically you're out. Altimeter is not really an altimeter. Yeah. Yeah. It's just a, it's just a barometer like your granddad might have on the wall.

13:30

Yeah, house. Yeah, haven't you got one, yeah I have. I have got a barometer well then and then basically it's just someone's painted over the barometer with without you. It's a lie. It's a lie. Yeah. But everyone's telling the same lies. Why at the same time?

13:44

Yeah. So that's fine. So it's really a pressure measuring device that we can use to approximate our altitude. And I think, the more you appreciate that will perhaps, try and store that away. The more you will just always have in the back of mind that there's a limitation to this device.

13:58

That is so crucial to the operation. And, and not put all your faith into it, because obviously, there's accidents, where incorrect, pressure settings, or problems with the, the system and failures, of course, like big loss of life. And I just like also you know, understanding that the pressure is higher sea level and the pressure.

14:22

Reduces you go up for one simple reason gravity. So obviously the effect of gravity is stronger towards the earth so the air is denser and as you get higher and higher and higher, the air gets less and less dense. And so I just I just like the simplicity of that, but the relationship of pressure with height is not linear and temperature it is but that but we rely on the temperature might not be.

14:51

There's all these problems with our altimeter but we get it to work through all sorts of international standard atmosphere and then these super, super accurate altimeters which are just measuring pressure. Like, see practically. So I just thought. So I'm like if you go from A to B on one zero, one three and you're going from high to low, then to high pressure again, you're actually riding the 1013

15:13

Like isobar almost. Yeah. And we're all doing it. So, it's fine. Yeah, you're actually going up and down. Yeah. You just have no idea because when I'm sat in the cruise, and I want to feel like I'm sat on the top of like a tower, that's labelled, FL350 and then my aircraft dips, or the speed, like just very slightly and I get annoyed with it.

15:34

Like, what's this doing? Little do I know, you know, like I always say we try and operate the aircraft so precisely to the nearest foot, you know. It's the nearest kilo of fuel flight to the nearest knot of airspeed, but the environment that we operate in is so imprecise.

15:49

And this is like the best example of it. But because what is out, what is altitude is? Yeah, it's a lie. It's a lie because we just use this standards kind of 30 feet per hectopascal. For example, you, you're talking about your your wave of 1013 if you took off somewhere, pressure, setting of 1030 and flew not very far.

16:12

Maybe a couple of hours to someone that was like, 1 0 0, so 30, millibars different. Yeah, you actually will be like a thousand feet lower. Yeah, the time you get there but you wouldn't know that because you asked me to still read the same. Now it's a massive fudge.

16:28

And then when you think about you think, well hi what's the what do they call the earth is oblate? Spheroid with the geodetic mean, so the ground is growing up and down. Anyway, yeah, as much but at least everybody's just doing the same thing. So hopefully hopefully with these super super accurate and then this is the problem, isn't it?

16:46

Like the air is there's a lot more volume to the air than the ground. We're light used to be in these 2d people really who live on this one plane and it's like, I so crowded down here. Yeah. But then, you know, like a skyscraper of apartment shows you how much more space there is when you go up?

17:04

Yeah. Right. That's why like, you know, when it's 5pm and everyone leaves the offices and then they're all stuck in traffic because they all live in high. They'll work in high-rise officers and then there's only one plane for them to drive on. Yeah, right. But in the air, there's loads of planes because there's well a thousand feet every time fee.

17:22

Yeah. But the problem I'm saying is we all fly so precisely and laterally on navigational tracks, that sometimes you can go ahead to head of an aircraft. Yeah, which is ridiculous. Yeah, so like we offset our lateral tracks sometimes just to introduce a bit of randomness but we don't offset vertically.

17:39

Probably for good reasons. But you know when I was doing GA I used to fly around like at 3,000 feet exactly or something. So everybody I should have just like, yeah, shit. I just feel like maybe was I doing the wrong thing, you know. introduces some randomness. Yeah.

17:53

It's everyone's at 3,000 feet is true. That's true. And and then perhaps before we move away that just the the idea that yeah, when you, you're basically measuring the out, another way to think of me is you're just measuring the weight of the column of air above your aircraft and so if if it's warmer or cooler, that affects the density of that, that thing that that you're measuring.

18:16

So yeah altitude is BS, but it's super important. So we've established it. What's your favourite pressure setting? I've never really thought about that ,1013 probably. Yeah, and when I'm doing like simulators running simulators, it's just easier to just do one two or one.

18:35

Three serious. Yeah, that's not realistic. Okay, sorry. Well, I was gonna say, so, it all works as long as everybody's doing the right thing and we fly around on standard once or one three to get to where we're going. And then we start descending to to land somewhere and this is the more dangerous way coming down.

18:54

Yeah going you know doing your altimeter check is you mentioned on the ground that he threw at the start of the day is fairly straightforward because you're on the ground. You checking the elevation and you take it off up into the air? Yeah. Well there's nothing. You're gonna hit coming down towards the terrain and the ground.

19:08

That's where problems are going to arise and going back through the transition level onto local QNH. You have to change your alternator setting. Now this is where this is where problems can occur. For example, with like language barriers, etc. So you often hear this set QNH is mm-hmm.

19:29

So if you heard, if the QNH was say 1013, when you heard 1033, that's 30 big problem. Yeah, that's already said what? 30? Well, yes, goals is a thousand feet, so known as a problem for the ground, that's pretty bad. It's also a problem for other aircrafts because they, that was obvious.

19:52

Yeah. Well, like the different, you know, like a few hundred feet might be easy to miss. Yes, that's true. That's true. And that could create and, you know, maybe we'll talk about this, but on a non-precision approach. Yeah, that could kill you. Well, yeah, exact on an non precision approach.

20:08

The QNH is the only thing that you're flying on with reference to the ground. Really? I was thinking because sometimes do you ever think about? Like the end of the world situation and somehow you've got your hands on an aircraft and you're gonna go and fly your family somewhere. Alright?

20:21

Right. So you've got no air traffic control. Yeah. So you can set the QNH yourself on the ground. Yeah. Because do you know the elevation the airport? Yeah but if there was never any radio communication with the ground and you were flying somewhere different and you had no met information.

20:35

Yeah. How could you ever know what the local pressure was? You have no datum, you wouldn't to come into land because if you are flying to a remote airfield, like in general aviation, you kind of set the regional QNH, or sometimes they'll say, you get it from this airport and then you adjust it to this local airport or you?

20:56

Just there's a there's a certain tolerance or something. Yeah, if you had no met information at all, you would never know what the local QNH is. You just have to head towards the ground. Yeah, as the impossible, basically? Yeah, although I'm starting to think about other source that we've got on our modern aircraft.

21:13

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Radio Altimeters

So, the radio altimeters. So, maybe this good times to talk. Yeah, about that. So, so when, when might, you know, you've missed at the QNH then, well, so when you're already out to me, it goes off. So radio, altimeters are more accurate way of measuring your altitude.

21:31

Well, your height above the ground? And it's basically like a well, it's just a radio signal. Yeah, bounces off the ground bounces back to the aircraft and calculates your height in feet above the ground. That is directly below the aircraft. Yeah. So and it's important, if you're stupid like me, you might think it's called radar altimeter, but it's radio and it doesn't use.

21:56

So I think for example, like, combat aircraft would have like ground following radar to fly into enemy territory. So it's totally different to that and it's only it's just a simple radio. Yes, signal suit super high frequency signal between. It's about 4,000 megahertz, yep. And it's like some kind of weird frequency modulated thing and basically they bounce it off the ground and the difference.

22:21

It's essentially the time that they're measuring yet to your height above the ground. It's a slightly different and we got two of those anyway. Yeah, not just one. Yeah. See two those and that's a good point. Why don't we just gun then cross check? You know, you could cross check your yeah.

22:37

That's that might so where you would trap that you buy a miss set the QNA. If your radio altimeter is reading two and a half thousand feet and you're expecting your barometric to be the same. And it's not, that could be a catch, but we can't just to make the distinction.

22:51

We can't use that in the well, we don't use it anywhere above two and a half thousand feet. No. And I think due to the design of the instrument you can't. No because it'll be too much error. I believe you can't use it in the masking now why don't you just use that?

23:05

Yeah, but again like I said it's not relevant in the opacity because you want everyone to be on the same data. Exactly. You don't want to be some guy over one. Town is you feet higher than yeah. And if you see what it literally measures the ground right beneath you.

23:19

So exactly. So, you know, relevant so it's not relevant. There might be a massive hill underneath you. Yeah, you might actually be 5,000 feet above the aerodrome that you're landing at. But only two and a half thousand feet above the hill. That's directly below. You. Tell anyone else.

23:31

It goes off. He's flying across the Atlantic. Yeah. It's black at night. Yeah. There's nothing below you. Yeah. And it suddenly goes. “500” wouldnt is say “1,000”. Okay. Yeah. There you go. But a thousand. Yeah. Why is it done that obviously? There's an aircraft has passed directly below you.

23:50

Yeah, at a thousand. Exactly. A thousand feet below. You and obviously the audio J following it as well. Yeah, it can stay you radios right over. It has picked up the aircraft, believe you and thinks it's the ground. Yeah. Yeah. The use for thousand because it's on all the time.

24:04

Yeah and when the wheels when you when you have to've lifted off and so if you ever get intercepted by like a secret fighter jet or UFO, you would know about it. If you underneath you. Yeah. There's you can't turn that system off. So that's very accurate. And that is true if you like compared to this lie of barometric.

24:24

That is literally telling you to the foot. How high you are here above the ground. Yeah, and like you say, it's at that moment. So yeah, talking about the North England. Again, if you're on a kind of like bass leg for RWY23 Manchester, it'll go off. And when you're over there Peak District there.

24:45

So it's a trigger for most SOPs. I think when that goes off, you'd be a fol to ignore it. Yes. So what kind of what do we do when it goes off. So we've verify we you know, in terms of our situational awareness. We love hopefully pre-briefed where we expect it to go off, right?

25:05

And that will verify whether our position is correct whether we've got the QNH set correctly, did it go off where we expected it to go off? Has it gone off earlier than we expected? Does that mean? We're not where we thought? We are etc. Etc. It can help. I think I had it go off in a hail storm once actually but it's pretty good apart apart from very very rarely.

25:25

And yeah. So we we check our essay and including the pressure data. Yeah, at that point. Yeah we also use it for our stability as well for our stable call. Don't we? Oh yeah most airlines use similar but maybe yeah. Actually the thousand foot radio call 500 radio calls more infallible and yeah, not ignore the verbal.

25:49

You can't ignore the save The radio. The read radio, altimeter has a display on the PFD. That's how we know it. And it also has this beautiful like, the actual horizon, the the brown horizon starts to come up to rise. This is such a good display and even a red tape comes up.

26:07

Yeah. As you get close to the ground, but also and the manufacturer and the airline chooses certain callouts of, which there should be one at 2,500 1,000 feet, 500 feet your decision height. So you can use the radar to to ping to ping those off, which I think is what you're saying, which is, which is good.

26:30

So we use it for a thousand for another thing. It's good for is measuring the rate of change. Yep. So what system does it feed? That might be the last thing that could save your life in terms of controlled flight into terrain feast their GPWS, right? Exactly, yeah. Same warning system.

26:49

So all those like, you know, too, low, terrain warnings, terrain, pull up, those kind of things. It's the rate of change as well. Yeah. So it can't necessarily look. Well, it can't look ahead of the aircraft, although, we now have aircraft with a database over the map in, which helps the enhance.

27:04

But also, if the ground is approaching, yeah, then it then it doesn't, it doesn't like it. And but it builds a basin around there, an airport to allow you to, to get close to the terrain without spooking it. So now and then it's, I don't know if it came in at the same time, but it's really crucial for one of our automatic systems for auto land.

27:25

Yes. Yeah. So we wouldn't be able to auto land without the radar altimeter, radio alternator. I see. This is the problem. I feel like I want to say that. So to be clear it's the radio. So yeah. So that's how the aircraft manages to do. What we normally do that eyeballs.

27:43

Yeah. Which is flare and which it does a really good job of really good. And it's the height of the landing gear above the ground. It's calibrated for. Yeah, I think that's why occasionally on the ground. It reads minus because then the landing is compressed, it's slightly compressed. Yeah, yeah, minus one.

28:00

I minus two. Yeah. Yeah. Don't come and see that. Okay, so you sort of touched on something else there, which we could talk about. So you mentioned, an auto land, we use the radio alternator. Yeah, auto land would typically be often ILS approach and instrument landing system. Yes, essentially flying a beam, both lately and yeah, vertically.

28:22

All like across hairs all the way into the airport. If you haven't got an ILS approach which a lot of airports don't have then you are flying. What we call a non-precision approach. Where we are managing the vertical profile ourselves and the only reference we've got to start from, is the is the QNH?

28:43

The? Yeah. So even on our approaches, although there's kind of more modern ways of flying those. They're still based on making sure that you've set the correct QNH. Yeah. Otherwise, nothing will save you. Exactly. Say, an ILS is a precision approach, and we like to fly now non-precision approaches as precision like approaches, which means that we're using, it's basically GPS.

29:12

But, you know, it could be your inertial sources to navigate an area navigation. Are you not following them down a beam? So, you know where you are, but you're not directly going in tracking inbound to something. So, it's a non-precision approach using area and navigation, which can be very, very accurate.

29:31

However, vertically, there is no element to it. So, you have to have the right pressure set in all your screwed. Yeah, GPS altitudes available, but it's not part of the approach whatsoever. No. So that's interesting say just to be clear for anybody out there that ILS is you could haven't, you could do it without altimetres, if you could lock onto that beam.

29:54

Yeah, there's a vertical beam and there's a lateral beam and that'll take you down to the threshold of the runway as well. So you all the way in, but on approach, you need to know that this distance from the runway. I need this pressure altitude. Yeah, yeah, exactly. So GPS altitude is not used by us at all, apart from in, sort of back door, play redundancy.

30:20

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Aeroperú Flight 603

Yeah, failure of the air data interesting that it's not, we might, we might cross reference it. Yeah, so lots of lots of potential. It's it's leading me towards a couple of accidents that I've looked into. Yeah. Okay. A couple of things that you've said. Yeah go okay well Aero Peru, okay what happened there?

30:42

Then I haven't looked at Aero Peru but I feel like I know the accident you'll know it. So unfortunately arrow Peru 1996 B757 the aircraft had been. Oh yeah on the ground and they covered the static ports with they call it like masking tape, some kind of tape. Right.

31:02

Wasn't picked up by the engineers, wasn't picked up by the Captain on the walk around took off and all hell break loose in terms of aural warnings and stuff because they essentially got ground level air trapped in the static port because it had been taped over. Yeah exactly. And so let's think that through.

31:24

So, would that affect their takeoff roll? No. No. Because the airspeed would come from the pitot. Yeah, but it's minus the static. Yeah. But say, wouldn't be affected until you climbed until you climbed when you when the static should decrease. Yeah, because we do cross checks on the air data on takeoff, which could prompt to rejected takeoff.

31:47

Yeah. So they got airborne and some pretty crazy stuff happened. It's really, it's amazing that they didn't crash for so long. I don't know what the duration of the flight was, but it makes for a really upsetting sort of series of events. Because this the situation awareness in the flight deck, sort of breaks down and down and down.

32:09

However, the first officer seems to have kind of a grasp of what might be the problem, but can't really convinced it's not that he's advocating it but it seems like he has more of a chance of doing the right thing. The couch in total loss of SA and I wanted to kind of work out if they had memory drills for unreliable airspeed.

32:31

At this point on the B757, which you assume they have all they are not. I wish I'd got to the bottom of that, but I haven't but they are aware that they have contradicting information. Yeah. Because the aircraft is they say over the radio all the time, the aircrafts accelerate in even though there are idle power.

32:53

And basically, they're stuck at 9,700 feet on the altimetres, right? And a lot of the time the GPWS system is aurally. Warning them. So unfortunately at some point they ask air traffic control. What their altitude is right? And the air traffic. Controller tells them, it's 9,700 feet and they accept that as a valid or one of the sources.

33:23

So it adds up to really break down their SA. But Sam, where's the air? Traffic controller. Getting the information. Well yeah from exactly the same source as they often that transponder. Yes. So the information that the air traffic controls got is erroneous, so just to be clear that thing that I mentioned earlier, height monitoring unit is so obscure we don't even know about it.

33:42

There's no real-time data for the out for the radar controllers on the ground to measure your altitude, geometrically or anything like that. There's nothing like that available. The pressure altitude that you have in the flight deck is transmitted via data. To the control on the ground. So if you don't know your altitude, they don't know on the ground.

34:03

So if you're in an unreliable speed situation, you tell them or possibly turn off the mode C of your transponder if the controller doesn't stand that. So in this accident, unfortunately, the amount of alarms in the flight deck was horrible. They also had like, you know, EICAS for like rudder and mack problems that were due to this and this chain of events, but it was just adding to alarms alarms alarms.

34:28

So we don't know what their altitude was doing, but we know that the GPWS was doing, it was saying the right thing. So a lot of the time they're very low but we know their lateral track and the captain does kind of have a good idea. He's like, well, if I can get on the ILS then I can land.

34:49

Yeah, but at no point. Do they do the Unreliable speed drill. So and I've said this before but basically the captain had like 20,000 hours. FO first I've said like 8,000 hours staring at altimetres that were working correctly right now. They're not, but they weren't able to blank them.

35:08

No, you know, sometimes it'd be nice to have a sheet of paper and just put it above across the altimeter, or the airspeed. Yeah. Because otherwise, your eyes are gonna get drawn into it. Yeah. So I just so, your brain is saying, look there look, I've run this in the simulator occasionally just to show people where you get an unreliable static because we always do unreliable air speed right?

35:29

I've showed them a block, static pool. Yeah. And it's amazing that you can feel the aircraft climbing, right. And the pitch is climb pitch. Yeah. But the altimeter is just staying for. Yeah and not moving horrible. It doesn't feel right because we spent so many thousands of hours looking at it and it just isn't, right?

35:47

It's just not. So, that was so powerful for these guys that they disregarded the GPWS warnings, right? They believed, what the air traffic controller was telling them, but yeah. It just stayed the same altitude, the whole time. The display. Yeah. And then in the way it ends is horrible because they, they think they're sort of, they kind of trying to troubleshoot it.

36:07

There's not too much structures to it, but the wing clips the sea and they're like, then they they realise. Oh, we've just hit the sea. Yeah. But then they have another 20 seconds, maybe of of trying to climb out right. But I don't know what damages occurred, but they're still flying and in a even though they've actually hit a bit of the sea.

36:28

Yeah, it's crazy. And then eventually they get sort of go inverted and go into the sea, at this point, the FOs, trying to sort of advocate, a little bit that the GPWS is probably reliable is almost getting there. So, the things that we've talked about already, they're relevant, are that your instruments are fallible?

36:46

And you need to understand their limitations? Yes, that the ILS doesn't use any barometric data. So, apart from you need to find your way on to it. So how and something else? I think we picked up on was relevant to this accident as well. Of course, now we'd have GPS altitude data, we could kind of cross check that.

37:05

Well, that's bullshit altitude. And yeah, also just that the radar ultimate is totally different system. So if that's going off, you know, and we have specific training on this. It's not as ambiguous as I'm about to make out to be. But some, you know, what do you believe? Do you believe the stall warning

37:22

Do you believe you're a airspeed tape? Do you believe the GPWS system? Do you believe your pressure altitude? So you need to be aware a little bit of the technical aspects of these systems. Think which one? Which one is likely to be reliable? And what's the chance that they're both wrong?

37:38

That's how. Can my GPWS? And my barometric altitude. Both have failed today, but so many alarms in the flight there definitely wasn't helpful. I am say, that was one. And then unfortunately, another B757 took off in the Caribbean and an insect had decided to move into the static port.

37:58

I is, it's Birgenair and it is a charter flight and it and that had blocked the static port, right? And that accident is, my memory is failing me now but it was different but was blocked. Static port on our 757, not to not too long after so that's a shame but what I wanted to find out which I didn't find out.

38:23

Was now I feel like we've got very rigid drill for like if there's any ambiguity here? Yeah. About the air data. Yeah. Then we go into a memory drill. Yep. We it's a look it up or anything like that and we go back to basics if you like, which is pitch and power to power and we can fly the aircraft safely on pitch and power.

38:43

Yeah. And to a point where we can troubleshoot, but until that point, we don't look at one of the three and go. That's the right one. That's the right. Yeah. Because we don't know at that point, right? But it seems like and these accidents that that wasn't as explicit as like, okay you go into the memory journal so they're the accidents that I'd looked at specifically with regard to altimetry.

39:06

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Dambusters

Yes. So I I didn't look at an accident. I looked at something kind of more anecdotal and something I found really interesting and you talked about it, flying low earlier was the was the Dambusters, you know, you know that I love this. But and for any of you that don't know, sort of the detail about the Dambusters and I've only heard about it.

39:30

I'd strongly urge you to watch, there's multiple documentaries on it, but the one I watched was with Dan Snow the presenter, really, really interesting. But essentially, so when they were creating the bouncing bomb to try and destroy these dams in Germany, so much, testing went on as to what the perfect altitude or height was to drop the bomb to let it bounce along the reservoir and hit the down bear in mind in the, you know, 1940s the best altimeter out.

40:08

There was an old three dial barometric. Which, you know, would only really accurately measure to 100 feet. So it wasn't really, very well calibrated, but like I said, earlier, you can't ask the Germans for the QNH. No, exactly. Yeah. And yeah. Exactly. You can't ask me. Yeah. Just as you come into, German airspace.

40:27

Yeah. Anyway, so you say this, so what they found was that 60 feet above the water, was the perfect height to drop the bouncing bomb. So the question was, how do you fly at 60 feet at night without knowing what the QNH is from the Germans? So they came up with this really clever system, which was basically two torch lights mounted to the front of the, of the Lancasters.

40:57

And essentially, they were calibrated to such an angle that as the aircraft came over the reservoir at night time. Obviously generally, perfectly flat level plain the, the reservoir, these two torch beams move closer together and when they made a perfect figure of eight on the water light on the water, that was exactly 60 feet.

41:19

And I just thought that was such a nice anecdotal story of like, altitude and altimetry like 60 feet. These guys were flying out and literally just as simple as two torch lights. Yeah, could fly. So accurately. Right, what works? So clever ingenious way and then they would obviously drop then.

41:37

I drop the bouncing bombs from from that 60 feet. Say, I just thought I'd share that as a as a sort of little side story on altimeter, I like it because well there was a point in terms of navigation where we did it all by using ground-based system.

41:53

So you'd fly in towards the beacon and then turn away in the way you want to go outbound on a beacon? Yeah. And then we started using area navigation which we still use ground-based stuff. Now, we're moving to a world where it's stuff on the aircraft, you know, so you you're making on-ever approaches using GPS.

42:11

Yes. But then the GPS isn't actually on the aircraft. Everybody thinks that I'll never go down, which probably won't because there's multiple systems now, but it has caused accidents in the past and people have been shot down because of their navigation error. So in the same way, in terms of altimetry, it's like what can we have on board.

42:29

We got this wicked radio altimeter now which is but wonder if other on board stuff like the GPS will become yeah. Relevant you know, in the upper atmosphere or yeah. Possibly. But there's guys in the Dambusters they have to have everything. They're not gonna get any help from the ground.

42:47

Yeah. Yeah. Every system had to be on on board system. Yeah, you're not gonna have an ILS into your target site that bomb. Yeah. Everything had to be on board including the altimetry. So two, light bulbs, two light, bulb one, just had spare light, but what if the filament went?

43:02

Yeah. Exactly. I don't know. Yeah, I mean interesting, yeah, it was such a simple piece of technology but worked perfectly, you did your brain, you listen to the radio radio ultimate call outs when you flare not consciously. No. You think you don't do it on that or well. I I don't know, maybe I do more now as a training captain because they teach that that's how we teach it for.

43:26

People learning to learn the airbus and maybe I'm more conscious of it. Now it, what about like the texture of the ground? Or, you know, do you actually have a little of you have how low you are? Yeah, I think it's more on judgement now by just looking out the window and judging it was supposed to look at the end of the runway.

43:42

It's not that I'm saying. So yeah, exactly. Whereas I think in your early days, you probably did use the radio altimeter, more as your gauge to help you flare and land. Yeah, yeah. Well hope we've destroyed the concept of how to meet us. So next time passenger says, you know or you make your PA how high we are but I wouldn't suggest you tell the passengers.

44:02

We don't really know just so just guesswork. But we're all doing anything. Yeah exactly. Don't worry about it and yeah. I think we've then we've talked about some interesting, interesting, sides to our altimetry there. So yeah. Thanks very much, bye.

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Airline Pilot Technical Theory, Human Factors, Aircraft Accidents Adam Howey Airline Pilot Technical Theory, Human Factors, Aircraft Accidents Adam Howey

Oxygen

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Transcript Start

00:04

Adam Sam oxygen important. Yeah, oxygen. Very important to us in. An aeroplane, why is it important to us? Well, because we take the most precious cargo known to, man, take it up into the stratosphere and although there's a lot of risks associated with flying at 500 miles an hour in the stratsphere one of the biggest hazards to us is the environment itself.

00:31

So 35,000 feet. Well, the passengers are innocently sipping, their gin and tonic actually outside. It's minus 56 degrees. And the partial pressure of oxygen is extremely low. Yeah, so, I mean, what's your favourite attitude? Yes, 35 37. Maybe. Yeah. This is a point to be made there, which is it?

00:56

We could be between. Yeah, 34 and 40. Let's say, yeah, there's a big big difference between your time of useful consciousness. Like effects of a decompression. Just between a few thousand feet there. Yeah. It's almost like exponential, isn't it when you get up to those higher? Yeah. Because shoots are they, the partial pressure and the pressure is, it's reasonably linear.

01:18

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Physiology

As you go up, it's haemoglobin that is has the exponential change. So the haemoglobin the red blood cells that carry the oxygen around the body. They're 98% saturated at sea level. When you get to 10,000 feet, they're still 90% saturated. But by the time you get to 20,000 feet, they're only 60% saturated, right?

01:40

Just like an exponential decrease in the ability of the body to get the oxygen into the haemoglobin and anything you can really compare it. To being up with those, altitudes would be like climbing Mount, Everest people, you know, not everything's about 30,000 feet high and we never been saying everyone that goes to the top level is to generally use oxygen and because you just couldn't survive.

02:02

Yeah, he told me some people. Climb it without auction. Well, yeah, I think they do, but I think that takes them a long time because I think they do it and their climate is and they take things very slowly getting up to the top and base camp is like 20,000 feet or something.

02:17

So they have to acclimatise there, you climb there and then it's quite a slow climb, but I guess they're not. Then trying to fly an aeroplane at the top three or climb around, just doing kind of hopefully, simple ish tasks. Yeah. So space, you're saying they've got but they've got physical, they need the oxygen for physical activity, whereas we would like to say, we use it in our brain, our brain.

02:38

Yeah, the brain is like, really hungry organ. So, use a lot of oxygen. I say that's interesting because if anybody ever had the chance to experience the effects of hypoxia safely and, you know, volunteer to do so it's kind of would be really useful for your career so I mean how high is Kilimanjaro.

02:57

I think its about 20,000 and you can like kindly gently walk up. I think people can get up to something like that oxygen and stuff. Yeah, I mean you could hire a hyperbaric chamber or something because there's a list of common symptoms of hypoxia. But what is unique to you is that the order that they occur in.

03:17

So they occur in a different order to every for every individual, but they will always occur in that order to you. So, you know, there could be some use in getting hypoxia course. And then recognising what your first? Yeah, but yeah, they're physiology of of oxygen, obviously, without oxygen.

03:33

Eventually we die and hypoxia is lack of oxygen. There's different types of hypoxia. You know, there's toxic hypoxia which you can get from drinking alcohol for examp course, the gin and tonic I was talking about earlier, the passengers are already slightly ever. So slightly hypoxic. Yep, at the cabin altitude that we're operating at with an alcohol will affect the haemoglobin's.

03:56

Ability to saturation of oxygens, take up oxygen smokers carbon monoxide, the red blood cells prefer carbon monoxide. So they inhibit the take-up of oxygen you know and if you've got a faulty boiler in your house you know that could be like fatal to people if they're if it's got a serious carbon monoxide leak.

04:16

So that's called toxic hypoxia. But I think what we talk about today is hypoxic hypoxia which is just the lack of the oxygen or the pressure of the oxygen in the air around. You Interestingly, I remembered like when we were flying light aircraft. There was always a carbon monoxide detector on.

04:34

Yeah. In front of you on the firewall. And then I suddenly thought, why don't we have that, you know, aircraft but obviously we're not bleeding. We're not sat right next to the piston engine bleeding, the heat air like in a car. So heat exchanger situation. So maybe but then we don't have any kind of like toxicity.

04:50

You would think a multi-million pound aircraft. You think like one of those tiny little carbon monoxide sensors that cost probably like a pound? Maybe we could take one in? Yeah. Maybe I'll just take one in my flight bag So, yeah. So, okay. So we're kind of touched there on you mentioned cabin altitude so okay, so aeroplanes flying through the stratosphere, 36, 37,000 feet, there's not enough oxygen there for us.

05:15

If we were outside the aeroplane, right? So, our aircraft are pressurised to a, what we call a cabin altitude. So what, what is a, how does that work? What does what? What's a cabin altitude? Yes, it's not sea level pressure inside one, why not? Because I think it's a compromise between the safe enjoyable altitude of 8,000 feet typically and then how strong you need your aircraft structure to be.

05:45

Yeah. So there's a differential pressure between the pressure on the outside of the aircraft, the altitude that you're flying at and the cabin altitude is on the inside. And so there's a structural limit which is usually about eight or nine PSI and we have an instrument in the flight deck that just is, is what their differential pressure is right now.

06:05

And so the aircraft designed to that structural limit And so that means that the air inside the cabin is 8,000 feet. It's like you're at the top of an 8,000 foot mountain Although the aircraft is physically in the crews at 35,000 feet but there's a point where you've got a, you've got to go from sea level to 8,000 feet.

06:26

Yeah. And say the aircraft has these really clever computers. That makes the art of pressurising and depression areas in the aircraft like totally automatic. Yep. But I mean what would they have done before automatic systems like that? Going back a little bit. There would manually have to pressurise, cabins.

06:43

And even before that, then they just wouldn't have been that option. You just had to fly around it sort of lower altitude. Yes, there are lots of aircraft there, around, pressurised, military, aircraft and but there's general aviation aircraft there on pressurised, and so, whatever. The air pressure is wherever the altitude is outside the aircraft.

07:00

That's the altitude inside the aircraft to state this and so you probably only going to go up to 8,000 feet. Maximum some of these little aircraft, they like DC3 and stuff, you know, used to have to hop over the Alps with passengers in unpressurised. So you'd have to get, you have to find, maybe a lower bit of the Alps, and, but it's gonna be have to be like 10 or 12,000 feet, I guess, which is fine for most people and 8,000 feet.

07:25

If you just sat there drinking Gin and Tonic, you probably wouldn't notice much, but if you ever done any exercise, well no, not really, but I did fly with the Captain once who liked to do some light press-ups in the back of the flight deck. Okay? And so yeah, so if you're a passenger sitting, you're not really physically exerting yourself or mentally existing yourself.

07:45

Then 8,000 feet is fine. But yeah, as soon as you start to exert yourself, particularly physically, it does have an effect. You notice, I notice sometimes cabin crew mode, they've sort of feel a little bit and well, not on well, but just and it's generally because they're up and they're moving and they're working on the lifting and carrying to trolleys, and they're physically existing themselves.

08:05

Yeah. At the top of an 8,000 foot mountain in effect. Yes. So that's gonna be really noticeable to them. Yeah. Because there's ones with step counters. Like cabin crew know that they do, like miles of walking on a fly. Yeah. But like you say they're lifting and walking at 8,000 foot.

08:20

Yeah. It's the cardiovascular system in the heart. That feels the effects of hypoxia first, although the symptoms might be from the nervous system. You know, it's like your eyes and what else is the nervous system things? Are that things that list on the symptom first? Actually your heart say.

08:36

It's all right, if you're sat there but yeah, if you're gonna do some press ups. So you probably won't do as many as you do on the ground. Because once you start asking the heart to pump everything around, just being an 8,000 feet, where saturation of the haemoglobin is 90% rather than 98%.

08:50

You'll actually start to notice that. So what's the most common emergency non normal situation that we have or any pilot? Oh, yeah, medical emergency. Yeah. So any problems that about that you may or may not know about. If I take you up to 8,000 feet cabin altitude you'll soon find out about them, amplifies them, doesn't it?

09:09

Yeah. They're all exaggerated. I mean often have a medical emergency. You might divert. Okay, good. It's all worked out. Well, we've got there person off and then you know in the post flight review, find out that passenger was 98. They had one lung that lung remaining had pneumonia in it and you think.

09:28

Well they're not going to cope very well. Yeah, 8,000 feet. Exactly. And yeah cardiovasc any cardiovascular problems that you might have especially since they're the first that's the first system. Perhaps to be as effective by hypoxia are going to show up and pilots have, you know, strict, screening and cardiovascular system.

09:47

Yeah. And probably for that reason. I guess it's kind of a bit like pregnancy and limits on how many weeks you can be pregnant and then yeah, I find them. I don't think it's because like you're so close to giving birth that like they couldn't cope with birth on a flight.

10:02

Although it I deal, it's more to do with this kind of stresses and strains on the body of being late in the pregnancy process. Yeah. Extra oxygen and physical exertion and you know, your heart is demanding more. So I think that's more why they have the limits. So I'm pregnant when they're flying rather than the fact that they're so close to to their due date.

10:21

It's it's all these things that being 8,000, feet in effect, cabin altitude is going to do to the human body that it wouldn't do at sea level. So it's a bit stupid thing to say, right? But you know, I'm always saying that the best thing about the job and the worst or the worst thing about the job is whoever you're working with say they maybe makes or breaks the job more often or nice.

10:45

The best thing about the job, the person that you sat next to you for eight hours and they're like a total stranger and you might never even see them again, you know, depending on the airline but you end up having quite deep conversations. So you wouldn't have necessarily with somebody.

11:01

You just met. Yeah. Do you wonder if slightly it's because we're slightly drunk like slightly. Hypothetically sort of like slip into you know more. Yeah. Maybe easier why it's funny say that because yeah being hypoxic or slightly hypoxic is similar to the effects of being drunk, you know. And so yeah maybe you know every knows that when they have a drink in the pub this started to become a little bit more loose lips and yeah, maybe maybe there's maybe you've got something in there.

11:29

Maybe you want something, I don't know. But we should be used to it because we're doing it all the time. So you think our physiology would sort of a climatize not literally to it. So, let's talk about when things go wrong. Then. Yeah, so we've got this pressurised aircraft, but what if your cabin attitude starts to climb?

11:47

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Cabin Pressurisation

So very briefly, the cabin pressurisation system. It sucks air. In from the outside pressurises, it pumps it into the cabin. And then the most aircraft have, what's called like an outflow valve, which opens cracks open a tiny bit to just allow a little bit of air to seep out and it just keeps the not closed cylinder.

12:04

No, it's not completely closed. It's kind of almost flows through and keeps the cabin altitude at a constant or climbing or descending depending on on what you're doing. So obviously like old aeroplanes they have other like little areas where air can see power as well. So it's with door seals or cargo door seals or anything really you know, weak spots, basically, where air can leak out.

12:27

So this there's probably two or three reasons why carbon altitude your cabin pressurization system might fail and the cabin al's stupid. Start to rise it could be sort of slowly compression like a small leak but actually the system can't keep up with holding that cabin pressure. It could be some sort of explosive decompression like has been accidents before well like a, you know, a doors blown off or a hole in there.

12:52

A big hole in the aeroplane is caused like a rapid decompression or it could be a failure of the pressurisation system itself failing. So let's split it up like that then say this slow decompressions and rapid decompressions slowly compressions then yeah the pressurisation system fails. Yeah. And it's a complicated system because you using bleed air from the engines to two separate systems normally and then forcing air through this cylinder.

13:19

And then the outflow valve at the back quite easy to spot on an aircraft. And it'll always be open on the ground. Yeah. Because on the ground, you always want the to be no, differential pressure, otherwise you wouldn't be able to open the doors. Yeah. So, the aircraft quite cleverly knows when it's on the ground.

13:35

It must be fully open and it must quickly dump any pressure that it's got left inside. But I did once have a cabin crew. Very rightfully and cleverly who had been fly. I will point out that there was a hole opening in an aircraft. I think it was ours and should point at the alpha valve, which is a giant hole in the area.

13:56

Yeah. Quite right over to like point out something if she thought it was unusual but you can see them at the back, right? Of the aircraft seem to always be there on all aircraft types. Yeah. And they're sort of things that you want closed in a ditching situation, I guess.

14:09

But anyway, so it's a complicated pressurisation system. You could have a failure of that system. I've on a functional check flight, took an empty aircraft up to cruise and depressurized it as part of the check and we put our extra mass on and we see what happens to the cabin oxygen system is on, but you also check the leak rate of the aircraft that.

14:32

It's an acceptable level. Yeah. But the older, the aircraft, the more little leaks you'll have somewhere in the aircraft. So, there's the outflow valve and there's just generally little leaks around. So if your pressurisation system fails the outflow valve, a hopefully will close as quickly as it can to seal you in as much pressure.

14:52

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Sams Experience of Slow Depressurisation

Yes, you can. Yeah, but the aircraft's going to leak out from all sorts of places, and you would assume a new aircraft would have the least amount of leaks basically. Yeah. So I actually had this for real once, so those bleeds air systems that you talk about that, that bring the air in from the outside.

15:07

So, both of those failed are on our aircraft. So we were climbing about 25,000 feet, outside cabin pressure inside. Probably at that stage, would have been about six or seven thousand feet and climbing up towards 8,000. And yeah, so we had no new air coming into the aircraft. So the outlaw valve closed and basically, then, yeah, the cabin altitude started to rise.

15:31

Even though we started to descend basically through the leaks, you know. And I recall, looking at it at one point and the cabin altitude was climbing about a thousand feet a minute. So from 7,000 we knew we had about three minutes for it would get above 10,000 feet and start setting off alarms in the flight deck.

15:52

So are we did a not I wouldn't call emergency descent within a fairly rapid descent from 25,000 feet and we just got down to below 10,000 feet as the cabin altitude was about 9,800, something like that, where we equalised basically and it just just avoided setting, the setting the warning off.

16:11

So, what I was the cause of all this, as this was a, this was actually a dual bleed failure. So there's a bleed system on each engine and by pure bad luck, both of them failed, one, just after takeoff, and we were sort of dealing with that fault as we were climbing up when the second one failed at 25,000 feet.

16:31

And I guess, although that sounds like really unlucky. What was happening was your aircraft was putting a lot of demand on the one remaining. Exactly. Then cause that to fail. Yeah, exactly. So you got down to 10,000. Why 10,000? That's that's the kind of accepted altitude that there you know, there's breathable and you got useful consciousness but also that's what the aircraft sort of trigger is for setting off the alarms to tell you that you're going to put 10,000 feet cabin altitude.

17:05

I think it's actually 9,800. I think it is actually I think this is really annoying. So why remember is it was it was it was the actual cabin altitude was flashing like 9,700 or whatever it was. So it was given me it was given us the advisory that it's you know you're getting very close here basically.

17:22

But yeah I think I think it's 9880 or something like that is where the warning actually goes off. The 10,000 is higher than the 8,000 were normally used to find out. Say vulnerable people with health conditions or elkly people might not do that well at 10,000 but they're probably survive while you sort out the problem.

17:38

Yeah, but let's let's think about this. So you needed to do not an emergency, you decided, you try and beat the cabin out to you now. So, trying to get down them before it went above 10,000. Exactly. But what you know, what can you just send to 3,000? Well, because of where it was.

17:54

So as this is an old airline, I used to work for, we were in Malaga in the south of Spain. So not the worst for terrain, but there's some fairly big old hills around Malaga and Granada. So our MSA, our minimum safe altitude was actually above 10,000 feet from where we are, so we could start off our descent quite quickly, but then we needed to get our charts out and just figure out exactly where we are in exact get to somewhere that we knew was safe to go below 10,000.

18:20

Okay? So we wouldn't hit the mountain. That would be terrible. Shame to have, you know, saved everybody from hypoxia and death, but then, ploughed into a mountain. Oh, yeah. But I mean, why that is one of the reasons to climb the aircraft. Like we said about getting everything else.

18:34

A yeah, trains always in the way, isn't it? And whether and traffic and so on because you just stop, you making a quick to send what about a cabin crew, what happened with them? So not huge amount they called us first actually. So as we were starting the descent, they obviously noticed.

18:49

Hey, you were supposed to be climbing back towards Manchester now. Why are we descending back towards the ground? As I think they called us first and we briefly just explained what the issue was. However, they had no indication in the cabin that there was a problem with the oxygen because the cabin oxygen masks don't drop down to actually 14,000 feet cabin altitude.

19:14

So actually, we never got anywhere near that. We never triggered the masks in the cabin. They were only aware of a descent basically say, call us. That's interesting. Let's come back to that, then cabin crews procedures because they're very involved in emergency descents, they're part of the procedure so you had a slow decompression.

19:32

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Rapid Decompression

Yeah, exactly. You said that there was such things a decompression. Yeah, there's some quite like you leaded to you, dramatic accidents, which began with rapid decompressions. The one I can think of is where there's that 737 with the whole top of the aircraft missing that was like in Hawaii, wasn't it?

19:50

Aloha? Yeah. Yeah. I mean that was just crazy. Yeah, Aloha 1988. Unfortunately. Well, the crew did really well the but one person died, which is one of the cabin crew. She was stood up when the decompression happened and was it metal fatigue? I think and then weeks, oh yeah, a whole of some size opened up in the aircraft and then the cabin crew along with probably lots of debris got sucked towards that hole.

20:14

And then makes the whole bigger impact of that actually made the whole bigger. Exactly. Yeah, following that cabin crew were trained and just generally became where if you hear a loud bang that you dropped to the floor and hold on to something. Yeah, even in that Sioux City podcast, we did.

20:29

That's what one of the crew did when the engine failed was instinctively just hit the floor because it's that was cabin. Crew that died in that accident, but this the picture of that aircraft is amazing. The Aloha. Yeah, you've got the captain who got partially sucked out of their aircraft British airways 1990 out of Gatwick, I think.

20:49

Yeah, Gatwick and they diverted, in Southampton, I think. Is that right? Yeah, yeah. So it's amazing story behind that but they basically not put the right bolts in the windscreen and say that that blew out and so they had explosive decompression right in front of the captain. Yeah, he was half sucked out and would definitely look at that another time.

21:07

Yeah. That's probably a good accident to look at in the whole podcast. Really. There's even I think a Qantas flight where the oxygen cylinder that provides emergency oxygen to the flight deck, blew up and close and explosive decompression. Well the coke can analogy is imagine a can of coke that you shake up.

21:23

So I know you may really violently. Yeah. You want to drink. Yeah, yeah, open this. Yeah, that coke can is basically one, aeroplane is flying through the air. It's like highly pressurised and the different pressure pressure between the pressure inside that coke can versus outside. Yeah. In normal, air is like huge.

21:40

So you were to pop a hole in that coat. Can I either open the lids or just stabber? What used to do in school, stab a compass in it? Or you did? What about those Americans on videos now that like, bite into it or something? I don't know the drink.

21:54

Yeah, maybe you should. Yeah, but as soon as you like, pop a hole in that, everything's just gonna fire out of it because it's trying to equalise the pressure. Basically it is a good analogy because yeah. Yeah thin aluminium. She basically diffused. Like, yeah, but the physiological effects then of being instantaneously taken from 8,000 feet cabin attitude to the outside because how long is it gonna take like seconds?

22:20

Yeah, there's a face to the gradual decompression. We're talking about in one or two seconds or something. This amazing change in air pressure. So what are the physiological effects? Well, there's one way I could put it which is what a train. It wasn't said to you and me on our MCC course, right?

22:38

I think he said something going lines of it's like having two red, hot poker sticking your eye, two red hot poker stuck up your nose and one red. Hot poker stuck like somewhere else where you wouldn't really want it. Yeah, and that's how he described his experience of when he had an explosive decompression.

22:55

So he's saying to pain the pain from those orifices. Yeah. Yeah. You know is that intense? Because the space, your body is full of gas. Yeah. So it just wants to leak out is once. Yeah. So if you've been holding in politely, something. Yeah, this coming straight out. Yeah.

23:10

And unfortunately, gas is gonna leak out through what did you say? Your eyes and your ears? He said eyes. No, but he said the pain from like your eyes, right? Okay, I guess this. So, how was that gonna do if you're trying to fly? Yeah, crazy. It's gonna be crazy, isn't it?

23:23

It's gonna be insane. I mean, the crew often tell you like some really unhealthy job and you don't know what they're really into and they'll point out their water bottles that you've taken from sea level. And then you've had a drink and close the lid. Go up to 8,000 feet and will expand.

23:40

And then as you start to descend all like contract and say, what must be happening? Just gently sector after sector to your organs and stuff. Like, I know it's probably not great for you but it seems to be, alright. But if you have an explosive decompression then you know, that's, that's pretty.

23:56

You know, what about didn't you take your girlfriend to the dentist and oh, it's explained aerodontalgia. Don't tell you yeah yes. So she always used to get pain in her teeth when she used to fly. And I think it was the dentist that when she explained it, the dentist like, oh yeah, that's aerodontalgia.

24:17

And basically where she'd had a filling and there's a tiny little sort of gap. Underneath the filling, whatever she went flying in an aeroplane that air that was trapped in. That tooth was still look kind of sea level pressure. And so like the fizzy coke kind of allergy. So really high pressure air inside her tooth.

24:38

Yeah. Basically, wanting trying to escape and get out and nasty. Yeah. She just used to get really bad pain in their teeth. Yeah. So you can see like some of the effects of the rapid decompression are going to be. I mean, we have dangerous part of our dangerous, goods lists of things we can and can't accept on the aircraft, obviously, certain pressurised things we can't put on the aircraft like you know all like Ross from friends on that episode he's nicked all the shampoo from his hotel and then when he gets back home it's all exploded in his major shampoo explosion in his suitcase and he's annoyed.

25:10

And that happens or like crisp bag. So is explode in the flight there which causes high minor alarm and you know how a lot of pilots have a little piece of paper which they write like the flight number on and their time of arrival and useful information. Why I don't do that.

25:26

People will think I'm a bit weird because I'm like, the only person who doesn't stick like this piece of paper to the instrument panel. But I always think like, even in the MSA on there great. But as soon as you have an explosive decompression that's going, it's got the first thing, our window.

25:39

Like also you get you know when you come you do a little bit of plane spotting, you see, in aircraft coming into land and you have that low pressure area above the wing and you get this beautiful instantaneous fog that appears. Yeah. And disappears due to the pressure difference.

25:55

Well, I believe same in the flight debt or in the aircraft. When you ever rapid decompression, you can have this sudden fog. Okay, appear. And even the instruments can have frost appear on them. Yeah, so I don't know what you reckon the first few seconds of an explosive. Yeah, these just crazy.

26:10

It must be crazy. It a us and say you've got memory items to apply in that moment. Yeah. And you've got what's the time of usual, consciousness, at 40,000 feet lights, but 10 seconds. 12 seconds? Something yeah. So you've got 12 or 10 seconds to put your mask on.

26:26

Yeah. Otherwise it's game over. You'll still be conscious but the chance of you doing the right thing. Yeah, you become like so. So drunk that you just can function, basically. That's the it's kind of the effect that hypoxia that quickly. So that's like that only thing anybody ever needs to remember about oxygen.

26:42

I don't care about anything else. The only thing any pilot needs to remember is that right next year, you've got this flight deck oxygen system available to you and you can just done your mask at any time and you'll be protected. Yes, the rest of the cabin might be in chaos and the passengers need to get their oxygen.

27:00

You're gonna have to descend the aircraft, but that can all happen in a slow calm time. If you don't have your oxygen mask on this game over, it's like the only thing you need to remember. But you can always to take off, can't you? Yeah. So if you ever put it on you know, what's the saying you if there's any doubt there is no doubt if you think that there might be some kind of decompression situation happening, maybe you've noticed something with your colleague or you just lost SA, yeah, just put your mask on, right, you probably never seen anybody do it, but I'm just saying, somehow get that ingrained in your mind that no one's gonna tell you off for doing that.

27:36

It's a slight tangent, but yeah, pilot incapacitation, if your colleague becomes incapacitated, even though it might not be obvious or there's nothing telling you as a depressurization or something through the oxygen. You one of my first thoughts would be do I need to be on oxygen? Is it is the first thing on the checklist consideration?

27:54

I don't think so. And I oh it's a really good point but it's something I don't think is on the checklist. Yeah. Because you don't know why they've become. You know, what exactly it could be like a loosely related to hypoxia like toxic hypoxia could be a fumes event.

28:08

It's not affected you miracly, you know. Yeah. Different people have the effects of hypoxia happen in different order for different people and also different ages and so on. So if you're the lucky one that gets to spot their colleague having incapacitation then yeah, she definitely think of the mask and you can always take it off is what I'm saying.

28:26

So you might decide, okay, we're actually safe and, you know, say definitely not pressurisation. So take a mask off. Yeah, yeah, time of useful consciousness. There's tables. It's going to vary person to person and so on, but you just need to be aware that exponential decrease, and the altitudes that we operate airliners are it's incredibly low, the time of useful consciousness.

28:46

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Kalitta 66

So, right sound. So I'm going to play you some piece of audio. We're just going to listen to it. Okay, talk about after. Yeah. I don't know anything about this. Okay. Right. Okay. Somebody read different sounds. Interesting

“Kalitta 66, Cleveland out here.

29:20

There, he's declaring an emergency with his flight control. Yes, sir. He said affirmative on that, right? Kalitta 66 Roger, what? Your intentions request vectors ypsilanti .

29:46

There is looking for vectors. All right Kalitta. 66 understanding the emergency. You want to vector to Cincinnati. Is that correct? Which is inflammatory. Beautiful landing, Kalitta 66. Are able. Are you able to maintain altitude? What what assistance can I give you other net? Vector and able to control altitude.

30:16

Unable to the control airspeed, unable to control altitude,unable to control heading.

30:31

Everything. A-OK. Okay. Kalitta, understand. You're not able to control the aircraft. Is that correct? That is correct. Kalitta 66. Are you able to able to land an airport airport that is closer to your position? Pittsburgh approximately now, southwest your position, Cleveland about eight miles, northwest your position.

31:03

Prefer aircraft destination airports and aircrafts is no damage to any more of the aircraft. So always ever so slowly with regaining. control. And if

31:45

Whoa, Kalitta 66 is able to send and maintain flood level. 260, they have to play two zero, let a 66. Are you still requesting a vector for a Ypsilanti? To the right of Kalitta 66 area. Precipitation 11 o'clock and one five miles extends, approximately threesome reflect Looks like and Roger 11,000 + 66 quoted 60, six.

32:54

Roger say, say intentions. Definitely anything plus 66 Roger Clear Delia Salini via direct maintain improve contact.” So would you make that? That's amazing. I've never heard that before, and that's incredible. So, what was happening? Well, obviously, it was hypoxia and but I've never, when, when did you get to that?

33:49

And well, I kind of had an idea that we were talking about oxygen, that maybe that's why you you'd played it, but I've never heard or seen hypoxia in action, really? Yeah, I just sounded drunk basically. It's like a drunk guy. Yeah. What's your favourite line? Everything say oh okay yeah I know apart from like the funny control heading altitude and what's interesting is that the the second pilot came back towards the end there so you could assume that he was maybe like unconscious possibly or just completely out of it.

34:25

Unable to key the mic to like press the microphone or whatever. Yeah. But then they both come back towards the end and they just sound like normal. So let's let's talk about what happened briefly say and it's a little charter company Kalitta and the flight is clear, six six and it's 2008 and it's a learjet 25.

34:46

The aircraft is gradually slowly depressurised not rapid decompression. So slow decompression, the pilots have become hypoxia and one of them is talking on air traffic control is saying that they've got problem with their flight controls in the face of other aircraft trying to relay and saying he says he's got a problem with his flight controls after a while.

35:07

One of the air traffic controllers works out that they think he's hypoxic yeah and so they managed to convince him to descend. Yeah. And as they descend into air with a higher pressure of oxygen, the effects of hypoxia on seemingly, both of them but one of them first just instantaneously wear off.

35:26

Yeah, I think one of the things that contributed to saving them is the or pilot was disconnected. And so they were able to sort of just tell him to do descendants. He's kind of went for it. Yeah, like a lot of accidents. Thanks. Unfortunately, to a serious accident with loss of life, many more people are able to, you know, have their lives safe because what we learn, and this is a good example of that.

35:47

Because it was the same aircraft Lear, jet 25, suddenly and accidentally 1999. And where the pilots were hypoxic in the aircraft crashed is actually with the famous US open champion Payne Stewart on board and from that the air traffic control, had some kind of training or awareness about hypoxic pilots and picking up the symptoms.

36:06

So the two air drive control. Is there the one you can hear which is Marvin. Marvin. McCombs and Stephanie Bevans were got awarded for their for saving. The saving serious accident by recognising hypoxia here but what an awesome, you know. That's right. But yeah party really powerful example that like said I've never heard that before is.

36:28

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Emergency Descent

Yeah, it does incredible. So talk to me about emergency descent, what, what's the outline of them? Yes, and emergency descent. So, this is going to be following one of these rapid decompressions that we've been talking about. Does it have to be? Yeah. After, can you mention any time I guess?

36:48

Well, yeah, I guess so. Yeah, it's no reason why you couldn't, but it would typically be it be if the cabinet is above his plan or is uncontrolled or uncontrollable. Yeah. So some useful consciousness, we talked about very small. So first action, protects yourself, get your oxygen mask on.

37:09

And then the next action is really are about descending. The aircraft into richer air, oxygen richer air. So starting a descent and helping to speed that descent along with maybe some extra drag speed breaks or possibly landing gear depending on limitations speeding up. If all of, it's not such a big structural damage.

37:33

So just basically getting the aircraft down as quickly as possible. However, there are it's not just as simple. As, as you said earlier, this end is 3,000 feet. There's all sorts of things to consider as well as controlling the emergency descent and everything it's going on. Within the aeroplane, you've got to be aware of what's outside the aeroplane and where you're descending to and where what sort of airspace you're over who, what other aircraft might be around what?

37:58

Terrain might be around. Yeah, so we always sort of thing, fly navigate communicate. So they're first actions of the emergency descent our memory items and the very first action almost, I want to say it should be an instinct. Now, memory item to put your mask on. Yeah. And then compose yourself to start the emergency descent, which is a two crew thing.

38:17

Then you've got navigation, there's gonna be weather terrain other aircraft and communicate to air traffic control that you're doing this descent through all of their layers of airspace. Yeah. And what kind of rate descent might? We I think probably like if everything and your favour could probably go up to 6,000 feet, a minute, maybe.

38:34

Yeah. Yeah. This is a lot, which is a nice rate, but occasion to where I exceed 5000 feet per minute in a normal set. Yeah, yeah, maybe more. Yeah, so you look there, I mean, I must say necessarily get more, but yeah. Yeah that's capable easily capable of dinner, six thousand feet per minute.

38:51

Six a minute from 36,000 feet. It would take you six minutes to get to sea level basically. Okay. So maybe sort of four or five minutes to get to flight level 100. So it took about masks, then you talk about cabin oxygen systems earlier on. Yeah. That they're very different to what the flight deck have.

39:08

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Emergency Oxygen Systems

Yes. How does their cabin oxygen emergency? Oxygen supply work. Yeah, so the cabin oxygen masks the drop down from from overhead. They are depending on aircraft type, would be triggered at a different point but on our aircraft it's about 14,000 feet but they're not pure oxygen. They're like, it's like a chemical chemical reaction.

39:29

Basically, which are oxygen into their oxide. You, when you pull the mass towards you, it's our first thing in there. Safety video that starts looking for the pin out, which starts these two solid chemicals. Combining in one of the byproducts is oxygen. Yeah, which is what you want. The other one is heat.

39:47

Yeah. So I think it gets quite hot. Yeah. I've heard that, but importantly, what you are saying is that those masks will fall down of their own accord. That system is independent. If the cabin attitude goes above, 14,000 feet on most fleets, right. We can manually put them down. Or if you do a really hard landing, a couple of them might fall down.

40:09

Yeah, because they are, you know, they're just sort of ledged there. Yeah. Ready to drop? Yeah. And but they should drop automatically when they're cabin altitude is, you know, let's say, 14,000 feet or above what the cabin crew gonna do, when, although sudden the mass drop. So when the mass drop that should be the first sign to them that something's wrong with the oxygen system, just so if they aren't feeling the aircraft descending at that point then there's a possibility of the flight crew and not aware of a problem so they would probably want to protect themselves.

40:42

First of all get themselves onto some oxygen and then contact the flight crew to see what's going on. Basically did have to give the flight crew a little bit of the chance to get their own oxygen on and start a descent. Typically probably a mint, 30 seconds, a minute or so, maybe a little bit more, but if they're not, if they're noticing that the aircraft's, not descending after 90 seconds or so, I think they would then begin on to contact them.

41:03

Yeah. Say be laid down in their manual, specifically. And it's actually mandated by your aviation agency. Probably worldwide that they have to be part of this procedure. So if they see the mask come down, they have the same masks as there, passengers. It's the same one that they do in the demo.

41:18

We pull, they pull them towards as they have them in the toilets in the galley, with the little bag. Yeah. Because this is a chemical reaction, it just starts producing oxygen. So, if you're not breathing it, it just fills up in the little bag. That's the whole late thing and then they're going to be part of our procedure.

41:34

IE, they're going to come and check that we are alive or aware of the situation, excuse me. If we haven't started a descent and probably made a PA saying everybody get on oxygen. Yeah. Okay so in the flight deck, very different system which we've talked to a little bit about.

41:52

Yeah, but that's oxygen supplied under positive pressure. So when you breathe in, that's when the oxygen is supplied to you. Yeah. Just rewinding slightly the cabin system. How long does that last? They recommend 15 minutes don't they? Yeah, the minimum of 12 is it over 12 but sure, yeah.

42:10

Typically that's what's the difference on long haul, you might not be able to get down quite so fast, depending on where you are, if they're placing the world where the mountains are. So, the train is so high. That you might actually be intermediate levels for a long time, escape routes and drift down procedures and things.

42:27

Yes, I guess. It's not sure how long a whole thing. It's if you're in Europe, if it's a. Yeah. Exactly. But yes, Central Asia and Greenland there isn't anywhere for you to be able to get to 10,000 feet within 12, or 15 minutes. Yes. You have to have a cabin system that can supply oxygen to passengers.

42:45

While you first probably get down to like 20,000 feet. Fly. Some complicated route called oxygen escape route. There's laid out in a chart down a valley to eventually get to the closest place where you can then descend down to 10,000 feet before the cabin oxygen system runs out. So sorry.

43:04

Going back to the flight there oxygen system, that's totally different. Yeah, and depending on what setting you have on your on your mask because it's designed to provide positive supply of oxygen either a hundred percent or mixed. Yeah. And depending on what you said, like depends how long it lasts and how many people are in the flight deck.

43:23

And so on. Because we also use it like we've already said in fumes and smoke situations. Yes, not just for decompressions and don't forget you. Preflight, checks are pretty important. Remember in British Airways 09 is that the we've already done in a podcast, the Jakarta we're all engines failed.

43:41

Yeah. So they start filling up with kind of sulphur smoke. So, decide oxygen on the first off to play his mask on, on the hose wasn't even connecting. Yeah, that's right. So, they decided to do a descent to get, some outside air breathable air, which coincidentally happened to save them.

43:59

But anyway, just one more oxygen system, a therapeutic oxygen. What's a most airlines will carry all? That's probably will carry some therapeutic oxygen and so that's to be used for inflight contingencies, you know, somebody falls alien flight. I think people can pre-order it as well possibly. If you've got a medical condition you can have it pre-ordered through your doctor that you're gonna use the onboard therapeutic oxygen to help you through the flight.

44:23

Yeah, therapy, say it as the title suggests I guess it's for medical. Yeah. Reasons either exist in or you know, things that can't fly but can be used in decompressions. Yeah. How would you use that if you? Because it's portable basically. So they can use it to move about.

44:41

So it just be the oxygen cylinder with a mask attached to it. And so, once they've maybe got over the initial rapid decompression, whatever that might have been, where they've jumped onto a one of the passenger oxygen masks. They can actually, they always talk about how they would like, sort of monkey, swing.

44:57

Yeah, between mass to mass to mask. It's really so they got to the galley and we're able to put on a portable oxygen bottle and because they're not nicking the passenger ones. No should be a spare one in each row. I think this is a row of three four four masks, right?

45:11

Yeah for infants and children stuff. Yeah camera. We've got to come in potentially in a D pressurised, aircraft to check. We're okay. And so they would do that on the therapeutic oxygen. They can change the flow rate and then last a while, and you've always got a load of those bottles on board, which part of the MEL?

45:27

Yeah, this is something like cabin crew number of cabin crew. Plus you something oxygen bottles. So yeah, quite a lot. So fit your own mask for helping somebody else advice. Yeah, because, you know, you're useless to anybody and you never they're never gonna get their oxygen. Say going back to protect yourself.

45:48

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Helios Airways 522

First. Yeah, always put your mask on. I think we're leading towards an obvious accident 2005. 2005, August 2005, helios five. To two is what we're gonna talk about. And so many lessons learnt from these accidents. Look at that collider. And and and say, by studying these accidents, they shouldn't have happened.

46:10

We can prevent them from happening again. Definitely a lot lent from this one. So this what the second for Boeing 737. We're going from Larnanca in Cyprus. Yes. To Athens. I think it's gonna get a Prague. Yeah, both stopping in after Athens. Not the longest flights. Then, no, the crucity a couple of hours, the aircraft had some previous pressurisation problems, which they've been looked at by the engineers, but somehow whether intentionally or by mistake, I don't have it.

46:41

My nose here, he'd left it in manual mode. That was my understanding, so rather than this, automatic pressurisation system had been left in the manual mode which means that the pilots would have been required to control the pressurisation themselves. So just to be clear the aircraft that was its own pressurisation, but if you've got it, if you've got a switch set to manual, you're telling the aircraft don't.

47:04

I will control the outflow of valve valve. Yeah. So the automatic aircraft won't pressurise at all or won't changes settings. It's all. So it had em. It had a history of potential, pressurization problems and door seals. So how common is a door seal issue? Yeah that does that happens quite a lot you quite often, get I find cabin crew will call and say, oh, it's a whistling noise by the door and you go out and yeah, sure enough.

47:30

It's sounds like a seal gone. Possibly on the door, a little bit doors, get open and close all the time and then there's all crap on the floor and the cleaners are coming in and out. And yeah, they are really well designed doors and on Boeings, aren't they all plug doors?

47:45

Yeah. Go in and then plug, but not on air bus but there is a rubber seal, basically, at some point, like, you would expect to seal the door. And if there's something caught in there or the seals, the t-rated, differential pressure is quite high. So you certainly get this horrible high pressure squealing where the air is leaving, but that's okay.

48:04

Because as we said, it's not a closed cylinder but it's something that needs to looking at. So it definitely had some of these issues if not other issues with the pressurisation system. Yeah. And say there was a British engineer stationed in Cyprus, nice custody job for him. Aircraft comes in, does a check on it, you know, daily nightly sort of check and looks at any problems.

48:24

So while the aircraft have been sat there overnight, he's ran some kind of authorised procedure by the book, probably to pressurise the aircraft on the ground and then go and look for leaks in the way that Boeing of exactly told him to do that. Now whether or not he didn't follow the last line of the procedure.

48:42

If you like, I don't know, I never got to the bottom of but I think it's established that that engineer did leave the switch in manual. Yeah, you would assume the procedure the last line of procedure was set it back to auto but okay so the engineers left it there in manual and then these two flight crew have take it from Larnaca to Athens.

49:02

Yeah. So I think the cockpit setup in a bowing is that both pilots for your PF or PM have certain systems overhead panels. And switches are your responsibility and on that day, okay? It happened to be the FO who would have gone through the pressurisation panel, but it's like a rotary switch.

49:22

Yes. Like I'm trying to describe. This is not a button. No, it's like a cooker, right? On a cooker. Right, right. Okay. Say it probably have like auto two and manual, you know, it was in manual. So I don't know how many times did the FF seen in manual?

49:37

Yeah one probably never. But how easy would it be to spy? Don't think it would be. That's really interesting human factors problem. I mean in an air bus, you have this lights off philosophy, which is really clever which is if the overhead panel is set up. You know, a normal configuration then this just no lights.

49:56

No lights. Yeah. But if you've left one of them off by mistake, then you'll see it straight away because it's suddenly a bright light on. But this wasn't the case here. So expecting a human to repeat the same action for however, many thousand flights they'll do in their career and even though 999 times out a thousand that switch will be where it should be in auto, your brain is going to get is, doesn't want to check it because it's like, why would I, you know, it's not your conscious mind.

50:27

Your unconscious mind is trying to save energy and I don't want to check that switch. Yeah, so in on one hand you might it might stand out in my life because you, like, hold on. That's which is definitely in the wrong position because I've seen it 999 times in the right position, but my point being that also, if you don't have the rigour of looking.

50:45

And what's the saying like looking and really like checking what? You're looking at the output basically. Yeah. So they took off with the aircraft pressurisation system manual. So what happens next? So they start to climb basically and the cabin altitude was basically the same as the outside altitude and passing 12,000 feet.

51:08

So must be slightly different on the Boeing. They got the first alarm went off saying problematic, cabin, altitudes at 12,000 feet. This is the first and probably the most unbelievable like Swiss cheese element to. It was that that alarm was absolutely identical to another alarm which is a takeoff warning, config alarm and the crew just assumed that it was a spurious.

51:32

That's what an alarm. They might have heard a few times before, possibly in the simulator or as even one they would do every day, like to check. Yeah. Possibly, they'll have heard it. A lot and bearing, it's actually like a horn. Yeah, the exact noise at that horn is for two separate.

51:48

Totally separate things other things. But you would assume, I guess, the design of the aircraft thought. Well, if it goes over 12,000 feet, it's not a takeoff. Config. Yeah, the mind doesn't really work. like that. So they assumed because they heard it before as a takeoff warning conflict, that it was a spurious, takeoff warning, config and just saying that's going off at 12,000 feet.

52:08

So what have we learnt about oxygen? Yeah. So already possibly. They are slightly least potentially in the early stages of very early stages and they're climbing at. What? In 2000? Feet a minute. Yes, it's getting worse. So, yes, they, they kept climbing and then they eventually spoke to engineering, and it was actually, the engineer that had done the overnight work on the aircraft that they spoke to in how they how they call engineer.

52:33

So they'd be calling me on, like, what we call box two like VHF channel two. Because busy that all the time. Like, talk with range. Yeah. Talk to call the engineers. No help you out. If you go a little problem and I guess if you've got satphone, you can do that anywhere in the world.

52:47

So they call the engineer who actually on the copy voice recorder. He actually asked them to check the cabin, pressure mode, whether it was in manual, but the report sort of said, that hypoxia had already set in and the captain, basically disregarded that question and asked about something else because what it was the avionics computers also sit in the pressurised aircraft and if the computers are in air which is unpressurized, the density, air is obviously much lower and so you need these massive fans constantly calling these really old computers basically in the avionics bay and they were the first things to sound the alarm, which is like they had an avionics heating problem.

53:32

Yeah. Because they're not getting enough air to call them down. So the captain was on the radio to the engineer saying I've got an avionics cooling problem. Yeah. And where am I CBs for the avionics cooling. Okay. And the engineer really cleverly, realised, that he may be confused and that's why I was advocating for him to check his cabin pressure and there's another little nuance here, which is you know, like the riga of small detail of how you should apply procedures.

54:04

So in our aircraft, if we have a master caution you should cancel the alarm and then you go about okay, what's the master caution? And yeah, and dealing with it and doing that all very systematically, but the very first thing you cancel it because as the way I understand it is, then if another failure occurs, the master caution will light up again and you'll be alerted that there is another failure.

54:27

Yeah, so the CVR for this accident is only 30 minutes of the of the flights. It doesn't go this far back but there's a possibility that when they got the avionics cooling caution, if it wasn't cancelled properly, then when they got a caution for the masks cabin masks, they wouldn't have seen it because I was hiding behind the caution, that was there.

54:51

Yeah. Well, and so just how, you know, a small discipline of things that the aircraft designers built in, you have to follow otherwise you open up more and more holes in the cheese. If you like, yeah, for these accidents to get three. So he's got Avionics cooling. He thinks and there is criticism in the actual report.

55:11

The non technical skills of the pilots there, which is really difficult for me to. Yeah, you know, criticise it's hard, we don't know when they became hypoxic, but there is that point isn't the way. You think you've diagnosed a problem? But you've got this has on the backyard or this uncomfortable, feeling that I've misdiagnosed a problem, and that should be a red flag to be like, let's go back to basics.

55:34

And, you know, is this an avionics cooling thing? There's one alarm, but it's not coinciding with this. But, meanwhile, what's going on in the cabin? Yeah. So the masks dropped in the cabin, cabin crew, passengers all using their chemical generated oxygen masks, but obviously, the aircraft still climbing. So I don't know why.

55:52

The cabin crew wouldn't have approached the flight deck earlier. Yeah, I don't think it was one of their procedures, no, one of their procedures but sadly for those poor passengers, their oxygen is going to run out in 15 minutes which is obviously what happened. Then they start breathing just outside air which is by now, almost cruising altitude probably 30th.

56:13

You know, they have seconds of useful consciousness and probably minutes of actual consciousness before everybody just passed out, basically, because you've got this tragic situation. Imagine if it was in a well, it is in lot, entries. And they call it like the ghost plane and stuff, but just before, it's really all over.

56:31

You've got this tragedy of. If you look behind the flight deck, door, a cabin full of all of the passengers promptly, put on their extra mass and been told to sit down and put their oxygen masks on by the crew, and they're breathing oxygen from this amazing chemical generated system.

56:45

And on the other side of the flight deck, door, you've got a total missed diagnosis of what's going on and pilots here, quickly become hypoxic and then lose consciousness. So the pilots in the flight, deck loose conscious the aircraft's climbing. It really high rate was cleared to climb to its cruise altitude.

57:02

Unfortunately. Yeah, 37,000 feet, I think and in the back patiently waiting is the cabin crew and the passengers for the pilots to do something. So it reaches its cruise altitude. And then the pilot string capacity is. So there's a loss of comms situation with air traffic, control and air drive.

57:24

You know, loss of comms is like reasonably common. I've even had it in that part of the world of had, you know, a few lots of cons. It's not always, you know, some massive tragedy, but the air traffic controls, don't follow the absolute correct procedure when the aircraft transits from the next ATC.

57:42

Based into Greek airspace, you know, the controllers are saying, here's my blip and you're now in control of this radar blip on the screen. It doesn't tell. Well, tells them, I'm having difficulty contacting them, but doesn't initiate a loss of comms procedure handover, which might have changed the situation.

57:59

But merely they climate thousand feet level off and continue on their navigation towards towards Athens and then the Greeks realise something's up and say what do they do next? It's point of which they send the military fighter jets up to intercept them. I've never been incepted but like they get pretty close.

58:21

I think these fighter jets. Well, I'm sure I read in the report they got so close. That the the fighter pilot could see into the flight deck. I mean, that's incredible for travelling like 500 miles an hour, how close you got but you could see the pilot slumped as the controls through the flight deck.

58:37

You could see all the cabin masks deployed. Yeah, as well. Yeah, you know, they are they love it. They can intercept like incredibly close and they are looking for hijack situations. So again, if you like looking really carefully but yeah, as I understand it, you can see their eyes, like, that's how place they are.

58:54

Yeah. So what's happening? I mean, basically brain damage is setting in there, say hi. These guys have been unconscious that now essentially dead already. Pretty much. Yeah. And the aircraft's flying along happily towards Athens and it gets to Athens and then goes into the missed approach. Hold. Yeah. So it doesn't descend ever is 37,000.

59:14

Feet doing exactly what the MCP pilots put in climb 37. Stay in nav mode and it just goes into the hole over here. Yeah you know KEA hold. Yeah. Yes I think it's an island. Is it to the south of Athens with a VOR on it. And there is and the you know, you've got this f16 following the aircraft, you remember what happens next?

59:33

So I think that at some point, one of the cabin crew is actually still conscious so one would assume he's been on therapeutic oxygen which lasts a lot longer. He actually gains access to the flight there. He eventually must realise something's wrong here. Like you know, this has gone on too long and actually gets emergency access into the flight deck finds the pilots slum to the controls tries to put their oxygen mask on to no avail.

01:00:00

But by this time times running out because basically the fuels running out. Yeah. So he takes the captain out of his seat. Yeah. And we don't know, but possibly applied oxygen to the captain. Yeah. How obviously, as well as probably the first officer as well. And eventually is seen by the F-16 pilot.

01:00:18

Yeah. At the controls and he could see that it's cabin. Crew, wearing a cabin crew vest but this guy isn't just any cabin crew, no. Didn't he have some sort of pilot's licence? Yes. Commercial parties licence yeah from the UK, right? So this is great, right? But the next thing that happens, two minutes after to not see the left engine flames out due to fuel starvation, and then four minutes later the right engine to dual engine failure, and some cabin crew of CPL is at the controls.

01:00:50

And probably this guy is hypoxic, yeah, because why he wasn't in the flight deck earlier? Yeah, when nobody's sure. But potentially, he was hypoxic and managed to kind of convince himself to get on therapeutic and started to revive himself, possibly certainly, it's hard to know exactly what happened but he tried to make four made a call on the radio.

01:01:14

And you know, what would he be able to do then if he, you know, say before before he ran out of fuel, you know, directly he could land it. I think he'd have a better than even chance. Probably, if it was no issue. I think a fully serviceable with the radio craft with a radio with some fighter jet help.

01:01:33

Yeah. I think story it would have been yeah. He'd like the total opposite but he transmitted a mayday on the VHF one frequency, which was like he is, you know, you have a few hundred miles back so nobody heard it. So I think he probably was hypoxic this gentleman his fiance, was cabin crew and she was on board too.

01:01:57

Now, the F16 pilot, there's an interview with him which is makes difficult to watch because he he's very upset reliving. This guy had to escort this aircraft as it ran out of fuel and just ascended towards the ground and totally helpless. I mean, this horrible and you can watch the head up display on the internet and you don't really get see anything, but you can hear the distress in there, F-16 pilot, it's voice.

01:02:28

Interestingly, they the cabin crew, that was at the controls is a bit of a hero because it's proven that he disconnected the autopilot, or used heading and turned away from Athens or built-up area. And as the aircraft like sadly descended towards some hills, he was making positive inputs to the controls of the whole time, right?

01:02:55

Up toimpact. And looking like he and to sort of do a control crash, but the aircraft in a dual engine failure, the 737 goes into like a manual backup made. So the controls are extremely heavy. This guy's hypoxic, you know, and it's the aircraft crashed in such a way that it was totally destroyed apart from the tail section, which has the helios god of on the tail, which sort of stood out, everything else was totally destroyed, destroyed on impact, really, sad and difficult accident.

01:03:27

It's obviously captures a lot of people's attention and is plenty of documentaries, but so much was learnt from it. So,, some mandated that cabin crew procedures have to be that. If there is the cabin, any signs of decompression or the cabin, oxygen system is activating the masks fall down.

01:03:45

The cabin crew, have to go into the flight deck. If they don't, if they're not sure that the flight crew are dealing with it. Yeah, which obviously would have saved this Boeing. How to redesign, I think even retrofit some of their cabin altitude warning systems, so that there's less.

01:04:01

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Ending

So there's no chance of confusion about what alarm was going off. And, did you know that in Sweden? Just a few years later taking off out of Stockholm at Bremen, there was an RJ, Avro RJ, jet that took off and part of that. I think de-ice in procedures whether you turn the packs off, right?

01:04:22

So these pilots took off with the packs off and the aircraft never pressurised. And so essentially a slow decompression as they climbed. And again, the cabin oxygen system, activated independently in the mass came down and everyone put their oxygen masks on. But this time, thanks to the lessons learnt here.

01:04:42

The cabin crew went into the flight deck and you know what they were doing, they would troubleshoot in the exact same thing. They were troubleshooting avionics overheat and had no idea about the cabin, pressurization problem, because for some reason, no alarm went off. But luckily, because the cabin crew came in and the flight crew probably looked behind them and got to see, you know, the oxygen masks and so on, they started emergency.

01:05:04

And and and thankfully like, however, many lives were saved because that, yeah, it's funny that in some of these accidents, you know, like the shell model. You know, the pilots have some information and the cabin crew and the cabin has other parts of information. The system actually had a complete picture of what was going on but it didn't all arrive at the pilots in the helios crash for them.

01:05:26

Say, you know, able to do anything about it. Just say, yeah, I mean hypoxia, the first effects of, by the way 1862, some heroes decided to take a balloon up to 29,000 feet, right? And reported strange symptoms, including loss of vision, loss of hearing and paralysis of arms and somehow in all that they were like, get a balloon down, you know.

01:05:51

Okay. Tell tell the story. I was like 150 years ago, the first like experience of hypoxia. Yeah, so there's one thing to remember which is that you've got oxygen available to you, put your mask on and then deal with the rest after the rest after. Yeah, that's it. That's it.

01:06:11

Get all right. Yes. Bye.

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Windshear

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Intro

00:01

Adam. Sam windshear. Yeah. Lots to talk about on Windshear. Only one word but it's actually quite a few words I've seen both. Well yeah, it's spell check always underlines it in red. When I write it's one word, so maybe it is two words. Have you been writing it to do some research?

00:19

I mean, well, yeah, exactly. Even on the bit I'm looking at now, is underlining red, but then I think maybe it's a dash, maybe it's a wind shear. Interestingly, the perps or I'll talk about the aviation community or the manufacturers they sort of refer to it. Probably encompass that word probably encompasses a lot of phenomena.

00:38

Yeah. They want in the pilots mind. It to just be a trigger and this means this. Yes. So as you could talk about what is wind shear, I don't know how far you want to go down that, but I think in its most basic. Well yeah, let's talk about this most simplest format like because I I'm haven't got very technical mind when we talk about explain it really simply so this wouldn't be technical.

00:59

This would be for their logical point of view, right? So, when I talk about meteorology, it helps me to remember that there atmosphere is actually a fluid. Yeah. Okay. You know, the birds would understand that probably more than us. Yeah. Where's sort of instinctively, I think if it's just like empty space.

01:19

Yeah, of course, that's not really what you want your pilots to be thinking about because there will be no lift if we didn't have, you know, the gas that we're flying through. So within that within that atmosphere, it's the transfer of energy into different states and it can be really powerful.

01:34

Yeah. So if you think about the way it's shear, you know, if you are on a cliff, you'd say is a shear drop. Yeah, that's how you could kind of imagine from that solid cliff shear drop now, imagine the invisible atmosphere. Yeah, well, you've got a sudden change because obviously as you fly through the atmosphere, the wind changes from zero to a hundred knots and there might be a slow gradient towards that.

01:57

But if we're talking about a shear that means a sudden, change like a, your almost exactly high point and all over a low point. Yeah. So that's how it helps me. Imagine what what you're looking at. Yeah, I mean that sounds pretty sensible and I think if you just googled definition of windshear it would basically sounds like you have it.

02:15

Well yeah it would. Especially say the difference in wind speed and/or direction. Over a very short distance. Yeah. So it's essentially what is so then meteorologically the term wind shear means that change in speed or direction over a vertical or horizontal distance and a short one, but what will probably end up talking about in some detail is the manufacturers practical use of the term windshear.

02:42

Yeah. Which if nothing else refers to a manoeuvre that you have to perform. Yeah. And I'm sure we're going to talk about microbursts quite a lot. Yeah. But it could be anything that causes you to perform that manoeuvre. It doesn't have to be a microburst. Yeah, well maybe we should talk about that first.

02:59

And so that is the obvious one which will maybe explain in a little more detail. But other things that I thought of was sort of topographical. So, so terrain being called that mechanical. I don't know which year, I think that. Yeah, yeah. And you also have well, you've got warmer.

03:19

Air descent air or cold, air descending on warm air creates this year. Yeah. And things like inversion layers. You've got a shear because it's kind of that classic like you coming into land and the tower says it's calm less than five knots or something. Yeah. But you look at your wind trend vector and you're only, I don't know if 500 feet and there's like 20 knots of wind.

03:37

Yeah. Oh, hold on. Some is not right here, right? Yes. That's could be no thunderstorms or mountains, anywhere near, but you can have like a nice calm evening, creating a shear. Yeah, so why, why is windshear such a problem to aircraft then? What is? Well, interestingly, you know, I sort of look back at the eighties in the 90s when I wasn't flying, an airliner and think.

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Microbursts

04:00

Oh yeah. They used to crash for all sorts of terrible reasons back then and but hadn't quite occurred to me that and yeah, this windshear problem was something they hadn't got a grasp of yeah, and killed a lot of people. I think in the US between sort of 1960, 1990, you talking about I've got the statistic here.

04:21

But yeah. 26 major accidents 2064 and 85. Sorry. Which is about 650 deaths. That's quite a lot really? Yeah. So they hadn't kind of got a grasp on wind shear slash microbursts. The first one that they directly attributed to was and some wing of a British airline, you know, back in 1956, whatever they record in Kano, Nigeria, sudden reversal of wind direction after takeoff that the pilot couldn't have known about, right?

04:50

So they were aware of it. Yeah. And but it was starting to kill a lot of people and this was at a time, you know, when we were trying to get accident rates reduced, seriously. Yeah. And so I guess we've learnt a lot since thanks to those people that have encountered them.

05:06

Yeah. Well that's the that's the class that we talk a lot in our podcasts about accidents and case studies. And I think what's really important to say is that when we do dissect them and talk about them, aviation has got to be one of the leading industries that looked back on accidents to improve for the future.

05:25

So any windshear accident that we look at and and talk about ultimately the investigation and fear into that, it's probably saved more lives in the future. Sadly, yeah. If if the accident, if it's an accident, which means loss of a whole major damage or loss of life, I think versus an incident.

05:42

Yeah, then unfortunately, something bad has happened, but we'll learn a lot from obviously. The idea is that we learn proactively by occurrences. I we nearly had this happen and so we learnt from it, but there's obviously a lot of accidents that have led up to and learning about how pilots and stand the windshear phenomena.

06:03

And I kind of got the feeling reading, all the accidents and transcripts. You're interesting to think. Yeah, well I would never put myself in that position but you kind of think they were in the wrong place at the wrong time and would I have done anything different? Because let's talk about a microburst.

06:20

I think it only lasts a couple of minutes. Yeah yeah. I mean you're pretty unlucky if you're that aircraft. Yeah. That moment on that airfield because regardless of fact that there was microburst conditions present which you wouldn't have perhaps understood 30 years ago but you might now you're still pretty unlucky.

06:37

If at the moment you are making your approach or takeoff that it decides to dump and sort of on top of you and also the sort of going into microburst now but the diameter of them. So it's less than four kilometres. Yeah is a microburst. Yeah well that's like your average runway length.

06:56

So yeah, that's interesting. So you know if it's just slightly over to one side it might not quite have the same effect. Yeah. See pretty unlucky and I guess that's why there are slow, is that right way to to get handle on it because they're kind of insidious and they're like, almost invisible.

07:14

Yeah. And these thunderstorms is people probably know about their formation of a thunderstorm, is it? It forms and disappears as quickly. Yeah, you can't put it in a jar and study it. Yeah. That that particular thunderstorm that cause that crash is gone and we can't see any car. Yeah yeah exactly.

07:29

So yeah so let's talk about the microburst ends. So essentially as a thunderstorm builds it's rocks energy up from from the ground basically to give it. Yeah. And as it grows and then eventually that air is cooled by moisture in the cloud and then it begins to fall in a kind of downdraft.

07:50

Yeah, I mean, thunderstorms are the example of what we were talking about which is the transfer of energy in the atmosphere and a really great example of mother nature, if you like right in front of your eyes. So yeah, you've got the energy latent energy. That's if you've got an unstable atmosphere, so air is rising meteorology.

08:10

There's so many factors and just you just one of them. Yeah. And then you get this big effect. Yeah, say a factory that is pumping out, heat might cause convection and if the environmental lapse rate is unstable, then all of a sudden, you get this runaway effect where you start to build a cloud, then a cumulonimbus or cumulus and cumulonimbus and then into a thunderstorm and with enough energy in certain parts of world, you can get these supercell thunderstorms, and it's the air that is cooling then condensing.

08:43

But then because the change of state into water, you then get more energy released, and it's sort of feeds itself. Yeah. And you've got different temperatures and then you've got draughts and you go updrafts and downdrafts and then you've got this machine and sky called a thunderstorm. Yeah. Yeah.

09:00

That's a really good way of explaining it. And so to say, keep it really simple. So these downdrafts, they kind of, I kind of best way I tried to describe it in. Simple terms, it's like anyone's got a Karcher or a hose, a powerful hose pipe. You just fire it at the ground.

09:16

Yeah. You know, when the water hits the ground? It just sprays off in all different directions, so say, yeah. Yeah. And so, for an aircraft coming towards that, so flying it, we've obviously fly airspeed. So initially, if you imagine you see the Google picture of a microburst you, yeah, you see it you initially gonna start with a headwind because it's spraying out from from the sides.

09:41

And if you go ahead when that's gonna increase your air speed, so the aircraft's gonna need less power to maintain your target speed, so you into a headwind, but then almost immediately that headwind drops off as you pass through the centre of it and come out the other side and you immediately turn to a tail winds.

09:57

So now your speed starts to wash off dramatically. Plus you've reduced your power essentially to cope with the headwind, right? Yes. So the aircraft's in a really low energy state plus the actual downward motion pressure from the downdraft is essentially creating this massive loss of energy in the aircraft and pushing it towards the ground.

10:17

Yes. And and now different numbers quoted but could be up to 6,000 feet. A minute down draft? Yeah, yeah, I mean flying through it. A CB is pretty turbulent and I think smaller aircraft would actually have structural failure. Yeah. Yeah. Because the draughts inside the cloud and then imagine these draughts suddenly come out of the bottom of the cloud.

10:37

Yeah. And then what you've just described is like the classic diagram of a microburst which is like you say this upside down, mushroom card, that is finding out. Yeah, it goes down hits the floor and then goes threads out, you get these horizontal winds then. Yep. And the classic aircraft that flies from one side of that diagram to the other and how it's like horrible trap.

10:59

So I mean most people will have experienced like oh there's a rain shower sort of coming towards you. You know, if you just a pedestrian or whatever walking around, you feel a draught. Yeah. Yeah. Associated with the rain is about to start or with the rain. It's exactly the same thing.

11:13

Yeah. And microburst can be wet or dry. Yeah. And that unfortunately means that we may or may not have an idea that they're there because of the systems will that we're used to pick them up. But the ones with a lower cloud-basing tend to be wet, but if they have a higher cloud base their brain often evaporates for you.

11:34

So, guess the ground. So yeah. Four kilometres in diameter. That diagram, you've just kind of disappeared from one side to the other. And yeah, imagine you're flying into an airfield and that happens to be over your effort at the moment you're making your approach. Yeah. Yeah, exactly. Yeah. And they say, we the speed that we travel, there's only 30 seconds to a minute.

11:55

Maybe. Yeah, that's kind of where that out if you're, you know, a thousand foot, if it's all happens really quick. Yeah, basically, yeah, exactly. And you can hit the ground in no time and that's it. And that's the going back to the blunt. Definition of windshear is a large change in speed of direction.

12:11

Over a very short distance. Yes. Essentially the markets like the west not. Well yeah the worst because the most common is low level windshear low level. Yeah exactly. In high altitude flight, if you go across a jet stream, you could you'll probably definitely have wind shear. Yeah. And and you might have lost controls all sorts of hazard associated with that, but at least you are not 500 feet around ground.

12:36

Exactly the low energy state at the time. Yeah. That's the big threat. Isn't it funny that you get those hurricane hunter aircraft to fly into hurricanes? Right? So how can they do that? But airliners can't make it under a thunderstorm. So looking into it. And that's a good example because this horizontal windshear in a hurricane and it's quite uniform as well.

12:58

And predictably, okay. That's kind of like an extreme version of those flying across a jet stream. Sometimes you won't get any turbulence. Yeah. And it's all horizontal shear, even though it could be a sharp shear. Yeah, but what we're talking about here is a big vertical component as well.

13:12

Yeah, funny as well, that I associate with aviation but obviously it's a hazard for anybody. So a lot of ships have capsized because of microburst. Yeah. So just as and has it for those guys especially sailing vessels with an actual sale. Fireman can be putting out fire forest fire and microburst.

13:32

Yeah, and I found a video of a toddler on a tricycle on like a Russian dash cam, right? And then he gets hit by a microburst really? And he's tried schools going backwards. Oh no, right. Okay, yeah, yeah. I mean I've never seen one no. I tried to see if they were present in the UK and there's this paper about one that may have happened in Farnborough in 1984 but that's how obscure they are you in the UK.

13:58

But of course, our job is to fly to other places. Yeah, well there can be large thunderstorms talking about as flying can you if you ever had a window? I don't think I've ever had even the reactive wind shear a warning. Go off pop from in the simulator, a lot of times.

14:16

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Predictive and Reactive Windshear 

Yeah so we practise it simulator, I've never had the reactive windshear from what we'll come to explain, maybe what if it's been reactive and predictive. I've had a predictive wind shear the holding point of the runway before. So the difference the reactive in the predictive or exactly as they say really are on most modern commercial aircraft, the predictive, it tends to be a function of like the weather radar, so it's pretty projects ahead.

14:40

It predicts based on the sort of moisture ahead of the aircraft and has a look and basically assesses where it predicts, there might be. Yeah. Some some windshear I found out it uses the doppler effect. Yeah. Like a traffic cop trying to do for speeding. Yeah, exactly. So they measure the change in frequency.

14:58

Yep. When they, I mean the in layers turns, they bounce microwave signal offer. Yeah. As it comes back, the change of frequency. Will give you an idea of that particles velocity and I think it's looking for horizontal velocity. I might be wrong about that, but that's all I've ever had is the holding point of predictive wiring.

15:16

We had a look on the path and it was kind of quite close to where we were supposed to be flying so we just held off for a little while. I reckon I've had scenarios where I think probably it should have the reactive so go back to the reactive will be right?

15:29

Well, what is the reactive that is an actual? Yeah, that's the aircraft fly control. Computers actually taking all the data and info from externally. And I think clearly it's a comparison of the inertial data with the aerodynamic data. That's all it does. Yeah. So what the aircraft should be doing?

15:46

This is first is what actually achieved today is achieving. Yeah. And it will trigger windshear when you want it. Yeah, so I've never had an actual reactive warning but I think I have I recommend conditions where it probably should have gone out but not because of a microburst, no, no because microburst know what because it's gusty?

16:03

Well. Yeah. Because because of the strong change where particularly thinking about sort of airports, like Gibraltar or that's okay, or Tenerife, you talk about microburst being the classic. Yeah. But these obviously, like sort of graphical? Yeah. Reasons. So you imagine. So for those, you don't know, sort of say Tenerife if you're looking at Tenerife from like a drone above the island, it's a massive volcano basically.

16:28

And the airport is right on the south of the island and it's at East West facing runway. So if you've got, like a northerly winds, that's coming down, hit on mountain and just like water, the air will just take the path of least resistance. So yeah, it'll kind of swirl around the base of the volcano and a bit over the top as well.

16:50

Potentially. Yeah. So you could be coming down final approach for let's say the easily runways there are nine, so you're facing an easterly direction and all of a sudden, you get a sort of tailwind from there. The wind coming around the base of the mountain, but as you kind of get to the wrong way, you start getting a bit wind, that's coming the other way around the mountain, that which becomes a quick, a certain headwind.

17:13

Yeah. Plus the wind that's coming over the top and down the east side of the volcano as well. I didn't a bit of sort of crosswind element as well. So you got changing direction change direction and possibly speed. And yeah, so that's it. That's kind of wind shear. But not and you're saying market but in your experience, the reactive when she hasn't gone off.

17:33

Yeah, yeah. So when I felt, you know, as when you sort of certain the city, you feel that loss of energy. Yeah. Because I don't know what the they don't really tell you what the threshold for the system is, no, but it kind of good. They doesn't go off I guess because yeah, yeah, I guess so is the aircraft in danger at that.

17:48

But then what about PIREP learn about windshear at Tenerife? I think, you know, a pilot report while it report on the, a s, it might say. Yeah. Like negative. windshear. Positive windshear. Yeah, so what does that mean? So that's in terms of whether you're, you know, air speed is gonna increase.

18:09

Like, so you're gonna get a positive shear or whether you're gonna lose energy negative windshear and they usually give it a knots as well as to roughly how many knots. Yeah, you can expect, if you get a negative wind shear, you lose headwind, you have it, you gain a tailwind, which the aircraft air speed indicator sees, as a loss of airspeed.

18:28

Yeah. So your ground speed would be the same, right? So airbus would argue, well, we already deal with that because you have you fly consistent ground speed because you've told us what the ground wind conditions. Are you input that from the tower eighties? You put that in the FMS?

18:44

Yeah, I'm based on that. It knows that's where it's ending up, anyways. What the inertial wind data is at that time and so it tries to fly a constant ground speed all the way down Tenerife Gibraltar. Yeah. Like who built an airport there basically. Yeah, we end up thinking to a massive rock or mountain.

19:02

Like we were saying about fluid. If if you have a stream that's running down picture a river and then you put a rock in the middle of the river. You will see the water tries to obviously flow around the rock in there. On the other side of the rock you've got little whirlpools exactly swirls.

19:17

Yeah, that's exactly what's happening or here where I live on the case or anywhere really. You get these big coastal winds and then as you walk between the buildings yeah, you suddenly have this incredible like 60 knot wind. Yeah. Yeah. And your hair goes everywhere. Yeah. And as soon as you're out of the gap between the buildings and you're actually on the front, it's less wind.

19:37

So you've gone through a shear. Yeah. Created because of the venturi sort of effect of the yeah, the building. Yeah. Yeah. So reactive when shear systems almost are like the more primitive but actually they do something different to the predictive but they came first. Yes, I think NASA helped design predictive winter systems and they tried a bunch of stuff were like using infrared systems.

20:03

That look at aerosol particles which are really tiny and but the the system we use is the weather radar which we use for all sorts of things. But the weather radar is also has this function of being able to use the Doppler effect. But like I was saying earlier, if the microburst isn't wet, it might not be able to see the wind because the particles until you small.

20:24

But the reactive wind shear is just like got its eyes closed. It's not looking ahead of the area. It's nothing like that at all. It's just comparing the air data to the inertial data. And it thinks hold on, why am I being pushed down into the ground when I've got a normal power setting.

20:40

Yeah. And airspeed. And so on. And so then it shouts windshear. windshear, and we fly an escape manoeuvre. Yeah. But getting back to what you were saying earlier about. You had one at 10, a reef. Yeah. Or were you saying them you've had predictive so? How to here about they're holding point before, takeoff.

20:57

So prevention is better than cure. Yeah, or we talk about thinking ahead and in my mind that's you can't go to heavy on that message which is you don't have to make that approach that take off. And this is possibly a message that wasn't sort of around back in the sort of 60s and 70s, you know, I think there's, well, I think there's three three sub areas as to why accidents related to windshear happened, a lot less now a because systems are better at detecting shear and with the knack, what NASA helped to build weather forecasting and assessing of caring.

21:32

What you're saying I was gonna ask you about how helpful you think traffic controller. Well, yeah, okay. We could talk about that and as well. But then also pilot procedures and I suppose, you could put it under crew, resource management, and SOP start rate procedures, you know, ways of actual procedures for dealing with windshear that maybe weren't there in.

21:55

Yeah, it asked. And and that, that's sort of helping to reduce massively the number of accidents. So yeah. So sorry. So you asked me about prevention better than the cure. So yeah, so airlines will have sort of procedures in place. Now, for example, in my example a predictive windshear before I took off.

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Prevention

22:13

Well yeah, the obvious answer, there would be to delay the takeoff but anytime you can run out of fuel you may. Yeah. Impacts on the commercials. Yeah, they're willing they're like oh okay. Yeah you're blocking you know, the alpha holding point. Yeah. Yeah. Something like that. So it's, you know, ultimately safety first, but there is obviously the commercial side of it comes into eventually, so maybe you're in the situation where it's actually safe to take off and maybe the water the windshear you've held off long enough that the windshear windshear alert has gone but they're still obviously wind shear around so, but at the aircraft is using its doppler effect in its same monitor radar display or windshear head, something like this.

22:56

Yeah. And what, what sort of information could you be gathering? I mean, I guess you've got the meta. Yeah, local sort of weather pilot report. Yeah, traffic control, maybe information. So there are some turnarounds where I've gone and stood on the steps and just took it in. Yeah, there's 360 panorama maybe of the airfield.

23:18

Yeah, you can. So you can understand what's that over there. Like directions, the worst weather in which way is best. You know? What is our departure? Taking us in that direction. Yeah. Yeah I agree. I agree. It's funny that and if you are the first one to say, I'm not going.

23:34

You might start chain reaction of. Yeah, we're not going actually, but it's easy. I think to say, well no prevention is better than cure. You know, shouldn't have made that approach in the first place but that's our job. Yeah, you said safety first, but you know, that there's a risk.

23:51

Yeah. That the wind shear will cause a loss of the aircraft and loss of life, but what's the likelihood of that occur in? Yeah. Okay. So what are we doing to mitigate that risk? We've got prevention, we've got windshear manoeuvre to escape. So, you know, we have to make approaches in weather in challenging.

24:11

Yeah, definitely. But we have also have to one day. Say not, not this time, not today. Yeah. What's a good piece of knowledge for me? I think would be to get an idea of how long that thunderstorms gonna sit there. Yeah. Because I've got a certain amount of fuel.

24:25

Yeah, so the whole point are in the air in the hold kind of have this feeling. Well, I've got to get on the ground somewhere, but I wonder how long I could hold, because even these microburst they only last couple of minutes you're not going to know if there is or isn't a market but of quickly a thunderstorm is going to move away from the airfield and that'd be good.

24:45

Good knowledge to have when you sort of planning. Yeah, I guess your fuel and your management. There is also things you can do to put yourself in a slightly better position. You can fly a faster speed if you're landing or take off. Performance permits it. Yeah. In land with different flap settings.

25:01

Yeah. So I think we're encouraged to take a stage of flat less on an Airbus flap three. That's for an escape manoeuvre. That will give you a better chance. Yeah. But if it's gusty conditions, you actually have better manoeuvrability with the standard flaps and so there's still nuances there and you can add airspeeds to approach speed.

25:20

Yeah. What else can we do? Brief rehearse, the manoeuvre. Yeah, very powerful tool to just rehearse the manoeuvre. So the first time you're doing it, it's not the first time you've what about monitoring is rolling the manoeuvre because I was gonna ask you what you thought about this because I just generally, if I'm PM read out a load of stuff.

25:38

Yeah, helpful. But I come to learn looking at some of this stuff that As speed might not really be a factor during the manoeuvre, so your angle of attack and your proximity to the ground. Kind of like the important things. Yeah, if you are saying the airspeed, I wonder if you'd actually almost tempted in the pilot flying to do something, they shouldn't do, because regardless, what the airspeed is doing, they shouldn't be reacting to that from my point of view, as any of this is, you know, as a trainer but as PM I wouldn't be so focused.

26:13

I try to think you know, and I'm in the simulator if I'm doing a windshear manoeuvre, I'm not really listening that much to what PMs, tell me, you know. Yeah. Speeds increasing speed. That means nothing to me. I'm just I'm doing the manoeuvre. Yeah. So as PM, what I try and do is I actually try and do the manoeuvre as well.

26:28

So yeah, that's more my focus on the meaning. That's obviously their first job of monitors to see that they're doing them an even correctly incorrectly, but yeah, in terms of actual information after that, just trying to be useful to try and say, but I just wonder if this is nuance.

26:42

I didn't pick up on that like telling the PF, how low you are to the ground is number one? Yes, you'd actually isn't relevant. It's probably less reverent. I do think simple. Terms, like climbing descending, like we're descending. Yeah, sending. That's probably the thing I learnt, I think I got this right there in the downdraft, the pressure can suddenly change.

27:01

And that will tell the VSI that you may be climbing or descending when you're not. Actually I really radalt is like the number one thing, because that's true. Yeah, that's interesting. Yeah, not talk about that. But yeah, I mean, when you're in a high workload situation, like a memory item.

27:17

Yeah. Potentially communications, the first thing, your brain shuts off. You might not be able to hear the PM anyway. Yeah, kind of easy for us to fly the manoeuvre now compared to before these systems, because we just have to follow the flight director, that's it. Yeah, yeah. Flight director is going to help us keep a high potential energy and then if hitting the ground becomes the threat, the flight director should just keep pitching the aircraft up until you're at the maximum angle of attack.

27:42

Yep, so that's quite straightforward. So that's so this is, if this is a change probably from back in the sort of 60s is that although there were maybe pilots had an idea of how to recover from a windshear there. Maybe wasn't sat down parameters for establishing when you're in it and possibly not specific procedures.

28:00

No, for getting out of it, you know some airlines call. It toga. windshear windshear. Yeah, the actual recovery manoeuvre. So on our currently, there's not many memory items like compared to what you'd think. But windshear is an absolute memory item. Yeah. So I think that's helped obviously over the years is having some sort of standard procedure to yeah.

28:20
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Delta 191

Escape manoeuvre basically. So let's talk about what they might have done before. They had an escapement over by looking at Delta 191. So Delta was Delta 191 back in 1985 so it was a flight from one coast to the other. I think across the states, but it had a stop off at Dallas Fort Worth which is where the accident occurred aircraft.

28:46

Not that it's really relevant. Was a Lockheed Tristar. Yeah. So how many I think there's three crew? Three crew yellows fighting. There was a flight engineer. Yeah. Yeah. Absolutely. From Fort Lauderdale on this leg. That's it to LA. Maybe I think it's going to LA but stop in it, but stop it.

29:02

Dallas. Yeah. Okay from why red there was sort of weather, Paul went half forecast in Dallas Fort Worth, the crew were aware of it pre-departure but also updating the weather on their way to Dallas. Okay? And as they got bit closer they had received reports of not windshear but rain showers, thunderstorms etc.

29:26

So this is continental North America you know we're talking potential for big thunderstorms even tornadoes in some parts of the country. Yeah today used to these things popping up. Yeah. And they I think they did some goods creatures some good avoiding in the early stages. So I I think the wrong ways they were landing on in Dallas was generally sort of north south orientation, their arrival initially, coming from the east.

29:51

But I think their original sort of star standard arrival. Procedure took them through some weather. So they actually asked for a different arrival, which brought them more northerly. And I have to say, I'm not sure about then, but now this states was quite different to Europe. Is the ATC have weather radar.

30:09

Yeah. And they do not expect you to ask for avoiding vectors. They give you them in advance as they get offended if you have. Yeah. Yeah. So, you know, they, they try to avoid by coming on a different arrival. There were preceding aircraft on that arrival, who reported? I think one reported line for a rain shower.

30:30

Yeah, one reported sort of light to moderate turbulence, but not more, was it? It was a leader. It was a sort of fairly light. Yeah. So there was nothing really to lead them into thinking. This was gonna be really, really bad. Yeah, and I've learnt that the two aircraft that were behind were interviewed and they their words were something online of all crews on those aircraft behind had no reason to do anything.

30:54

Other than continue, the approach, they were going to do exactly the same thing and they're very surprised when the aircraft in front crashed. Yeah, exactly. So yes, it wasn't. That would be interesting very reckless or anything like that. You know, say information they had there was an aircraft about to take off as soon as this aircraft would have passed in front of them.

31:14

And this aircraft take off path, would have been sort of more directly towards the thunderstorm and they were ready to stand up the throttles. Then they reported just after this aircraft crashed that their aircraft was rocking on its legs and their ASI. Even though their stationary on the taxiway, was reading 70 knots.

31:31

Wow. But they, he was about to take off about. So yeah, with no concerns, the they essentially they lost energy and crashed about they, like the classic they went to horrible way to sort of like summarise it, but they went through from one side to the other of the diagram.

31:48

It's such a short distant. Yeah. If you watch the computer and generated diagram of where they are on the glide path to CVR overlayed. Yeah, it's so quick so quick and what struck me? I can't remember the exact numbers but was the rate of descent. Okay was about a car I can't remember how many 3000 fpm.

32:08

Yeah, guys, it's converted from me to these are in meters. Maybe it's 3,000 feet per minute at one point and maybe up. It was, it was quite a normal rate descent on an ILS or 700 feet per minute. Yeah, so yeah, essentially for four times and if we got anywhere near thousands, we'd have to make calls as part of monitoring and basically go around pretty much after that.

32:28

Yeah. But if it's uncommanded, that would be extremely unusual. Yeah. So yeah, essentially so they got pushed into the ground basically. But actually I read that the aircraft landed in a ploughed field. Just just about two kilometres short of the runway. It was actually largely intact when it landed and it sort of skided along this ploughed field with everybody still alive, really initially it was only as it was sort of reducing speed actually got the highway and clipped.

32:59

Yes, like lamp posts. Then it started to break apart and something the water tower, then a big water tank. Yeah. And caught fire. And I think it was really the fire that killed, right? Most of the people almost everybody died. There was a few survivors he survivors at the back of the yeah the tail plane.

33:18

So it broke away and right, made larger intact and that's where most of somebody, I think died in a car here because, yeah, hit the highway. Yes, I bet. Yeah, they touched down before that bounce and then killed somebody in a car across the highway and then these water tanks.

33:31

I think they unleashed a lot of water, which made it difficult for the fire and rescue to the ground was waterlogged. Right. Okay. Okay, a swamp. Yes, yes, exactly. Yeah. Well I didn't know I didn't read that a weird sort of snoring like a river. If you're a. Yeah and all the crew died, they're CVR is available.

33:51

And you can hear the communication between the two. They're wonder because they not doing anything wrong at all, but the PM that was a captain, the pilot. Not flying was obviously telling the first officer about their airspeed. Yeah, so they're reacting to that. Actually interesting thing about Boeing aircraft versus our Airbus is if if in an airbus, you go to, you know, what you'd call firewall the throttle, levers, the threshold is sorry, say, you go, you take, that actually is a switch as well triggers a switch, which means that we're now in a mode where it's just going to provide, toga thrust whatever happens and on their aircraft not boeing but with a more traditional auto throttle, although they physically push the thrust forwards.

34:38

When the airspeed went really high, the aircraft tried to help them by reducing the throttle, right? Okay. Okay. So kind of something that we don't have to worry about on an air by aircraft or if you do the procedure right on any aircraft but that you want to be building up as much energy as you can as you travel through this.

34:56

Microburst. So even if the ASI goes high you then got a later potential energy in the aircraft which you could trade for altitude. Yeah. So at. No. And would you want less than four power? Yes. Even if your ASI certainly jumps some USB centily jumps high. Yeah, yeah. So that's unfortunate.

35:11

So yeah. So these sort of NTSB concluded as they always do. With accidents, is never. Just one soul reason. It's this, this Swiss cheese, we talked about, and if you removed any one of these items, it probably wouldn't have happened switch cheap. I have Swiss cheese. I mean lots of holes in slices Swiss cheese, and if you put all the slices together and the holes, like holes, all line up that does that's when you have a nice cheese without any holes and then holes in and can't pack that would prevent the accident passing through.

35:44

That's the kind of analogy the NTSB concluded and there's three main contributing factors and the first one that they should be to pilot error for flying through a thunderstorm. Right. So that time pilot arrow obviously made me mad. Yeah, it makes me mad as well because then that's, that was used.

36:02

But now we would unpack that. Yeah, to the end of the earth. Yeah. You find out what we mean by that pilot error? The second reason was an extreme weather phenomenon, what they describe is a microburst induced wind shear which is what we've what we've talked about and then the final contribute to factors they say was a lack of specific training policies or procedures for detailed.

36:22

So remove any one of those three. Yeah. And the accident probably doesn't happen. Which is typical for air air aircraft accidents. Yeah, of course you know if there wasn't the microburst then it probably wouldn't have happened and half as a minute later. Could have been a different. Yeah. Yeah.

36:38

Might have just made the difference between hitting the ground and not. Yeah. Quite a few of them in those statistics in that time period. Where they've lost 650 lives in those more, that would be like 30 years or something. There's a lot as well that got away by the skin of their teeth.

36:54

They you know, got really low managed to risk to escape it. Yeah. So there's plenty that we're nearly accidents. Yeah. Okay, say I guess they were getting fed up by 1985 then. Yeah. So this was a significant accident and the reason that we kind of picked this one is because this was, when they're kind of FAA, right, America decided, right, we need to do something about these accidents.

37:15

And so you alluded to earlier, NASA actually at Langley. They used an old Boeing 727, I think it was to sort of trial and test. This doppler-based weather, radar and creates some sort of wind shear alerting. Yeah, our system. And this was quite quickly successful and inserted on to.

37:34

So that would be PWS. That would be predictive windshear. Yeah, so I'm unsure the timeline but they also would have introduced the reactivity before the partitions I think. Yeah. It's now mandated that all aircraft have to have predictive. That's right. Yeah, absolutely same. Yes. So that was mandated by the FAA.

37:51

Do you know of any say even more up-to-date aircraft if they have any more advances in? And what I'm imagining is that their information from the ground. So their data uplink, all yeah. Is a feature, even in light aircraft and so position of cells with data things like this, you're going from a from aircraft-based systems to ground-based systems so you can gather more data, more data.

38:15

I don't know about specific, wind shear warnings, but certainly things like lightning, strikes and can all be overlaid on a map inside the aircraft. Yeah, radar and things like that. So, I wonder if that helps pilots build up a picture while I'm on that. Actually, I wonder and how how often do you scan?

38:32

The wind trend arrow and wind data. Their inertial wind data in the aircraft because it's on our end, you know our PFD. Yeah. And I don't really know that after, but I reckon I was thinking if there's a hints of wind shear or unusual wind activity, I might I'm looking at I am and I think I need to actually cognitively kind of look at it in a different way than normal.

38:56

Because that from what I understand is going to give you much earlier. Clue. Yes. Send your airspeed and actually date. There's a problem. Yeah, definitely. Because of course, we can do a windshear escape manoeuvre even if the system doesn't go off, we can just say look this is when she is switching, it's going to perform the manoeuvre.

39:12

Yeah so we have a set of parameters listed in one of our operations manuals which says if if any of these parameters are exceeded and it's that is a sort of self-diagnosed windshear. It's such in such an attitude change or whatever. I can't memorise that. I say I sort of just think if it doesn't look right.

39:29

Yeah yeah, that's the way I train it. I've got a sort of for our airlines numbers and yes they use. Okay. I saw easy way to try and teach people to remember it but yeah, absolutely. Ultimately in the heater battle if it doesn't such a pilot fray every day.

39:45

If it doesn't look right. It looks really wrong. Yeah. And then yeah absolutely. It's it's becoming unsafe and therefore you need to carry out that windshear recovery escape manoeuvre. So I wonder if we're gonna have a have one in our, in our careers. Yeah, I'm sure one day we will like say I've seen a lot of them in the simulator.

40:06

In fact, it's one of the current topics. We're teaching in the simulator. Yeah. When she recovers, most cruise really good at dealing with it, but they obviously know it's coming. It's likely to be that day that it'll come where. I mean, I've diverted because of it, but I haven't actually gone into it.

40:21

And at a point where the airfield had so many, and if that, I'd say the most common windshear that I come across, is because of buildings. Yeah, so low level around an airfield, you got these big hangers. Yes, certain specific directions of the wind are really nasty, create really nasty environments at one of the threshold, maybe a hundred feet.

40:43

And if every aircraft is getting a windshear and going around, I think what happened to the effort I was approaching was there. I will wish shut then. Yeah, because it the airfield is the hazard. Yes, everyone had to divert, okay. But it was there was no wind shear until you're on the lease side of that hanger just here, that's a strong stormy day but not necessarily wind shear from any kind of phenomena, until unfortunately, someone's built a hanger in the way.

41:11

So quite a serious topic but aircraft still crash because of wind shear. Yeah, so if not, we've not got rid of the problem, you know, I've got all these systems we've got this system. I was looking into that, they just didn't follow there, the windshear. Manoeuvres say, yeah, even though they had the alerts going off.

41:30

Yeah, cool. Well, if you want to learn more about windshear, that's a good accident. Yeah, to look at Delta 191, that's one. Where else did you say? Yeah, I mean, obviously the sort of your, the ATPL studies will have more of the theory behind what wind shear is, but I always find.

41:48

Yeah, just just looking at windshear related accidents. So I always talked about good for what wind. She means to us as pilots. Yeah, of course. This upper altitude stuff and we could do a whole hour on a clear attabellence flying through jet streams, upsets aircraft upsets altitude, but that's why that down for a future.

42:08

Alright, well, if you episode say next time, then? Yes.


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Jet Engines

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Transcript Start

00:00

Sam. Adam jet engines. Yeah, jet engines. Well this runs through your blood. You're from Derby, the home of Rolls-Royce. Yeah, that's right. That make really nice cars. We're all very proud. No! nothing to do with the cars, I'm not interested in the cars, my Granddad who I didn't meet spent his whole career there, designing and building jet engines.

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Axial Flow and Bypass Size

00:26

But yeah. And then so we used to go and look at their jet engines in there museum when we were kids. So when you see them with the cowling off. Yeah. And that's like, ingrained in my brain that image of a axial flow jet engine and because that always strikes me, when you see on an aeroplane, you think of it with all the cowling, but actually step back, the jet engine itself is, I wouldn't say small.

00:51

But comparatively well, the turbo fan that. Yeah, yeah. They now they're so I think the 777. Yeah whether this rolls Royce or General Electric or whatever that they're wide enough to fit the 737 fuselage in the diameter of the cowling but that's mostly the fan. Yes. Yeah. And then if you took the cowling off is what you're saying?

01:14

You'd see the narrow core. Yeah. That's a lot smaller. 

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Principle of Jet Power

Yeah. So a hundred years of the jet engine which pretty much is almost but going way way back before, then the principle of jet power. It was the first century literally in like the Romans came up with the, the concept they created a device which kind of directed steam power.

01:37

Yeah, that ball. Yeah. Three two nozzles in it and it's spun a little ball. Yeah. On a sphere. It kind of writes in like a nice way. It said this was just seen as a curiosity at the time. Like. Yeah, somebody looked at it went, oh, that's curious but didnt do anything about it. Would like Indiana Jones raiding some tomb, you know and then yeah, find one of these devices is like use to open some giant door or something.

02:03

Yeah, I mean what about those squids or something or octopus? They like jet out to move. Yeah. For it's for. Yeah. Yeah, it's always nature. Yeah. The principal has been around for a long time. Getting back to the jet engine Newton's. Third law. Yeah, every action. There's a equal and opposite reaction.

02:25

Yeah. So a jet uses that motion engine. You sometimes they're called heat engines and their chemical reactions. 

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History, Whittle and War

So 1903 with the right brothers. Yeah, but then by 1927 Frank Whittle was already trying to patent the, yeah, the engine I got a confusion to like who. Really designed the first, you think it was the Germans.

02:54

German guy sort of, he has a bit of claim to it but Frank is kind of got there. He's got it in the bag, really, but I did feel a bit, sorry for Hans, Hans von Ohain, who actually did do quite a lot of work. We didn't really know that whittle is doing some work.

03:08

Okay. In those and then like a lot of British things, we like just sold it because we were broke. So yeah. So the yanks took it. Yeah. Yeah. And I think like the rocket engineers that famously were invited to to relocate by the Americans and the Russians and who got the best rocket engineers?

03:28

I think there was a bit of that in Germany with the jet engineer, okay? And they ended up in France forming Snecma. Okay. Which basically is now CFM, okay? Yeah. Say there is some of that from from the war but little is maybe because we're British. That's what we hear about the most but yeah the Americans credit have us.

03:50

They always put Whittle at the front of their story as well. Is then they took his ideas, his ideas. Yeah. And this was all going on kind of during know, we're really like there is yeah, but even before. Yeah, yeah. Because the first test flight from Frank, Whittle on a jet engine was 1941.

04:05

So kind of just after the war started but obviously been designing it a lot before that. Yeah, so it just strikes me as interesting that this was all it was almost like a race during the war but they're never actually was a some jet engine aircraft during the war.

04:20

Yeah. So some of the stories are that the British were the ones holding it back. Right? And the Americans got wind of Sir Frank Whittle and saw the potential of it or some other stories are that they wanted to win this war and the jet engine was for the next war that was away, okay?

04:40

And the Americans more so so they so they were still fighting, they thought the wars would gone longer because as the European sort of situation was perhaps coming to an end. They were still improving the piston engines because they were fighting the war with Japan. Yeah, which is why I think perhaps they're an aircraft exceed far, exceeded like the Mustang is like a it's like a suped-up spitfire because it kept pushing and pushing.

05:04

That's the way my mind sees it. But yeah. So I don't know how the changing gets lost, but the thread of it is, although it was envisaged by Whittle and the technology was far, far, far behind what, they imagined and patented and designed. So when we talk about there, the technology involved today, it's easy to see that in the 20s.

05:28

They were, they didn't have a chance of achieving some of the things that they, that they said, but then the tent, the advances, in the jet engine, from that time to today. If you just track them across the, the decades in their own right, they far exceed like okay you think of the modern world now and the internet and electronics, stuff like that.

05:50

But we're talking about materials engineering and fluid dynamics and I mean, the engine has a real fast pace. Yes, like this machine, exponential kind of, yeah, right evolution hasn't it and reliability efficiency. All those things have just gone but yeah, you don't necessarily a second world war, you don't I think.

06:09

But they were flying the, I think the Germans claimed to have shot down like by 500 allied aircraft using their jet fighters, but it's a disputed a bit. But okay, they were the first to fly, but the Meteor flew as well.

06:30

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Centrifugal Engine Evolution

So they're all centrifugal jet engines which is like the first, so like the. So anyone who like me has got a brother who's bit, a boy, racer. Who's souped up his car. I mean, a lot of cars now have a turbo and a supercharger. Yeah, they are associated with, you know, high performance cars but now they they use them I think for efficiency as well.

06:51

Yeah. But essentially they were taking the piston engine to the limits and they were fit in supercharger to it. So the Merlin engine that I said was in the spitfire that sounds amazing. It's supercharged. So you've got to get more air into it and of course as you go higher you know, the air is thinner.

07:10

And so these are some of the limits of propeller aircraft. Anyway never mind the actual propeller. So supercharged means you actually use fuel and to draw in more so turbo users waste gas to to draw in more air and but a supercharger use actual fuel to draw in. And I think they just took the supercharger to the limits.

07:34

I'm not sure. This is Frank Whittle’s mind process but that's got so how it seems and then they just did away with the piston part of the engine and the supercharger is is is a like the first jet engines which is called a centrifugal change engine, which we don't really, I don't know where they used any more but not in commercial.

07:52

Aviation they use the axial long thin but they looked totally different but they were the first ones. So they would be what they're The Meteor, is the aircraft. Sorry. But the engine was like the W1 and the these are the first genes of the centrifugal compressors. 

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Jet Engine Technical Description

Oh yeah, I don't know how technical we want to go into the engine because you could spend all day about if you notice there in simplicity but appreciate people, listening will have already studied yet engines.

08:20

But yeah, I did look through the ATP owners about how much they learn about it. I mean, I I find that the physics if you like of it. Like I never find that easy. A lot of it is described through equations. Yeah. And but I find some of it interesting.

08:37

Like I think it's most efficient if the speed of the jet velocity is exactly the same as the speed of the aircraft. Okay. Right. When you put that in practise, it means a turbo jet is is efficient at about 800 mph. That's way too fast. Yeah. So the reason we use turbo fans.

08:56

Yeah. Is because when you do the basic energy equation, either what's the right time for it? It's you can either move a small amount of air really fast or a large amount of air really slow. Okay. And you get the same thrust, but one is way more efficient. Is that, right?

09:15

Yeah. That sounds pretty good. It's basically putting this massive fan on the front means that you move a large volume of air. A small amount compared to a turbo jet, which has no bypass. Yes. Okay, so, just to state, the obvious, that turbo jet is a really thin narrow.

09:31

Like, we were saying earlier, and the turbo fan has this giant fan on the front. So if you look at like early 737s, I think 1200, you and I used to sit at the end of the runway in leads at any, if you remember but Ryanair was still flying into leads at that time.

09:43

B737-200 or something, okay? And engines, really narrow. Yeah, you wouldn't you would stand out in my life if you saw it today. Yeah, yeah. They are actually turbo fan, but the bypasses is ratios really small, okay. So they're still not only that, they're not just here by jets and I think even military you're a fire and stuff is still turbo fan.

10:04

Yeah, but the bypass ratios much smaller. Now we bypass a huge amounts, not just efficiency, a lot of that is noise as well and those, do you still love that Ryanair 737 coming in because it made a loads of noise and there was like black coming out the back of here.

10:22

Yeah well yeah, so that's summarises. You see when you dive into the is it right with the physics? The engineering mechanics of the and the form is and stuff. I I find it interesting but that's how a lot of it's described, and it's not my strong point, but what I do like talking about, is there the components?

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Components

10:42

Yeah, let's do that. Very fact, because there may be people listening who haven't studied at ATPL. So, let's really simply go through the parts of a jet engine and how it how it works. Yeah, just in dead. Simple terms. So big fan on the front. Okay, what happens to the air next?

10:59

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Compressors

Where does it go next? So that's that's where you see the cabin crew posing for pictures sound there on the cowl in which is the nice smooth rounded thing that shrouds the front of the fan. Yeah. The bypass ratio means the amount of air that passes around the side.

11:16

Yeah this is the amount that goes through the core. Oh yeah. So the fan is actually like a propeller on a propeller aircraft. Yep. And it's driven by a spool that runs through the centre of the core. Yeah, to the very back. So So it's a power that fan.

11:39

You have to first get air going through the back of the engine firing and then the low pressure turbine at the right back drives the very front of the engine. Yeah. Okay. And that's moving the air that we talked about and that's providing thrust. Yeah. But some air then goes into the core and starts to get compressed.

12:02

Yeah, by compressors compressor. Yeah. Okay. So compressed like, more than we can imagine like the compression of yeah. Like to a serious level of. I think it's insane. I think Trent 500. It's a trend is a Rolls-Royce variant river Trent. Yeah. I one of my local rivers. Yeah. That means a three spool.

12:25

All the trents are three spools. Okay. But you and I fly there A320 series which are two spools. Yeah so you've got N1 and N2 readouts yeah see and then one is your low I want to say pressure low speed spool. Yeah. And N2 is there high pressure spool, But the Trent 500, which I think you would see on A330 something like that is.

12:46

Obviously now we're on Trent 1000 that draws in basically 200 metres in front of that engine, right? And is sucked in every second and ejected every second. Okay, so that's a, that's a kind of nice way to so don't stand in the front of it when it's no because you can.

13:01

Yeah, exactly. So the compression to achieve that, that's insane. And if you went back to Whittle, he would get not, not a lot. I mean, the principle is like it sucks in so much air. If you just if you take a jet engine, that's the same physical size as a piston engine, right?

13:20

The jet engine just by just for its size, and it's weight sucks in way more air. Yeah, than the size of piston aircraft about 20 times more. Yep, and that's because these compressor blades are spinning around and they're like little aerofoils. Yeah, which might talk about in a bit because it, we might have to deal actually with that as pilots.

13:41

I mean all this stuff. We're talking about now. It doesn't really know any of it needs to know what happens if you move the thrust lever,you go faster. Yeah, and so, little little aerofoils been around incredible speeds and behind stationary ones, and then another row.

13:59

So you'll have lots of rows of these things. And then, the reason you might have more than one spool by the way, is because as there as you compress the air, the actual duct that the air is going through gets narrow and narrower to the blades can be shorter.

14:14

Yeah. So it's actually more efficient if they spin a different speeds. Yes. And that's why you have different spools and a different stages. Yeah. Yeah. So they compressor my favourite bit for some reason. Okay, nice. Yeah. So then this super compressed air then goes into the next phase which is the combustion chamber.

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Combustion Chamber

14:32

So, it's When I've read, I always visualised it with just something mixed with a fuel. I didn't realise. It was kind of like a spray. A few, like a fine spray, isn't it? It's like very, it's like atomized. Yeah, exactly. It's like in when you spray your aftershave on.

14:48

Yeah, you see that atomizer? I think yeah, yeah. I'm sure it's more complicated than that. Oh yeah. I think technologically, that is the hardest part. That's so overcome because the temperature that you actually get to is too hot, I think to burn the fuel. Yeah, because as you compress the air, the temperature rises.

15:08

Yeah. The speed that the air is moving is too fast. Yeah. So you've got to have these combustion experts to like we've got to burn fuel in an environment that doesn't want to burn. Yeah, yeah. And say you've got to have these complex ignition systems that a continuous. And then, as you burn the fuel, I think it lights, other fuel and, but then, as they obviously all this expands, that's great, you've got this explosion and that's going to drive the turbine, the next part, but you want that flow to be not to turbulent and so on.

15:42

And so, it's crazy. I think it goes in it. 150 metres per second. I think, is the airflow into the turbine, so imagine how fast the airflow. Imagine trying to light a match in a hurricane. Yeah, exactly. Yeah, yes. So though, the jet engine you can explain it really simply in these simple parts.

15:59

There's actually so much engineering gone on around it to make it all work correctly. And you know, like you say like the ignition has to compensate for the speed of the air coming in. It's, it's fascinating really. So, yeah. So, so we've got the in simplest form, the three, three things and need for fire, really, which is fuel air and a source of ignition.

16:20

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Turbine

So, and that happens in the combustion chamber. So then where does it go to that? Will have the turbine. Yeah. So that that drives turbine. Yeah so it's really hot. Yes. So work this out the the temperature in the turbines like 1600 degrees Celsius you might be relevant later actually.

16:39

Yeah. And talk about some accidents but the materials used in the turbine melt at 1200 C. Yeah. Okay, so it didn't ask me! but, you know, a long time ago, early jet engines, I think 60s that time my granddad would be working there. They're using titanium for these components say that, that is a long time ago to be using these advanced materials.

17:00

Yeah, that's the only way they could. You know, that's that when you think of back in the 30s and the 40s, there was no way of them having this technology that time, but pretty soon they were onto these advanced materials and now they're way more advanced and I don't understand they grow these blades from single crystals and yeah, also things.

17:18

But these turbine blades, which I have one and have tiny little holes in and for coolinf and I don't know, other reasons, but they're spinning very fast, 500 metres per second. And each each blade has 18, tons of force on it. So fugal force, something like that. I'll try to find the statistic.

17:40

Like how many London buses you can? Hang off a compressor, blade or press play for a turbine blade. Yeah, by fine. It's like an insane amount. How many episodes so strong? It would be, it would be crazy. So compress is spinning round. Ignite the fuel, then you go into the turbine.

17:55

And then you've got again, like the compressor, you've got rows of turning turbine blades, and then stationary ones, little aerofoils, directing the flow, and we're doing whatever that you want to the flow at that point to make it smoother or faster, or yeah. So importantly, then you're a starting to extract the energy and drive the compressor, and drive the fan in a turbo fan.

18:19

Yeah. Or I suppose we're not really talking too much about turbo props and turbo shafts. It's basically helicopters but all of the energy in those systems is then it to the shaft or that prop. Yeah, as opposed to a change in where you actually using the exhaust velocity to have the nerds use third law and of reaction.

18:38

Yeah. So then you've just got a lot of not hot noise coming out the back and basically, which is great. Yeah, I feel like when I was like a young boy, that's so exciting. But now we want them as quiet as they exactly. Exactly. And yeah good. That's it.

18:53

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Summary of Airflow and Engineering

Really. That is how a jet engine works. It's suck squeeze bang blow. Okay. Yeah yeah like that. You learn that way. Piston engine say. So suck you've draw the area in. Yeah. Compress it explode with the fuel and then it blows the piston up. Suck squeeze bang blow is the cycle of a piston engine in a jet engine we call it the Brayton cycle, but it's exactly the same.

19:14

Yeah, so squeeze bang black. Yeah, I like it easy way to remember it but what was it interesting to me? Is yeah, the amount of engineering that's gone into it to because yeah, it's not it's not no part is ideal. So everything has to on been safe, for everything else that makes sense.

19:31

And yeah, has to come in at that speed. So how can we provide an ignition? So you know the same thing just has to survive, you mean yeah. And don't forget, we've got these engines running for what like 16? 20 hours a day. Yeah. They just want to be running all day.

19:48

Yeah. And eventually they get taken off the wing and they get renewed and but they're just running the whole time that these temperatures for the turbine. If you looked in. I think my, my understand is right? It's glowing red hot, those those turbine blades are yeah, they look like they're melting.

20:02

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Pilots Point of View

Yeah, yeah. And what we want is just like this perfect airflow through it, but obviously work as pilots we're like doing all sorts to to the with taking the aircraft into all sorts of places and in the environment and stuff. Say the engine has to put with a lot.

20:19

Yeah, but it's running that whole time. I mean, my friend who's more of an outdoorsman like when there was the Hudson Sully, Sulenberger when they're double bird strike. So I think he said, why don't you just put chicken wire on the front of the engines just like perfectly legit question, isn't it?

20:38

Yeah you need engaged down the engine. Yeah, you're into frame with this beautiful perfectly built finally balanced. Yeah. Mechanical miracle. So you don't want to throw a bird down it ideally no. So why don't you just put chicken wire in front? Well it's all about having this uniform airflow airflow.

20:56

Yeah, exactly. Setting the chicken wire would disrupt that. Okay. So maybe let's talk more about the commercial. Yeah, side of engines and stuff so they're reliability. What else we used them for what it looks like and it's sort of day-to-day so they're obviously very reliable. I don't think you've ever had an engine failure.

21:18

Neither of I I think you'd be, they don't start sometimes but sometimes they want the ground. But yeah, I don't, I think you'd be you'd be unlikely to have one in your career probably an engine failure. You might have one. Yes, seems to be probably, I don't know, 50% of people, maybe have one in there.

21:33

Okay, an engine failure. So very, very reliable, considering the amount that we fly. Yeah. The amount of engines that you, you know, you might find a four engine aircraft eventually. So yeah, a lot of engine and a lot of time flying them. Yeah. To not really have an engine failure, he talks about starting proceeds, sometimes they don't start.

21:52

They're obviously been automated a lot nowadays, so it's just, I guess the analogy similar to starting an old car used to have like a choke and then you had to. Yeah. And then but then that evolved into like an ignition and like, yes and accelerator. Now it's just like a push button on most cars like you just press the start, is yours push to start?

22:13

Yeah, mine isn't okay. So yeah, okay. But it's, whereas an aircraft engine is similar. Yeah, has to have to, you know, manually start the engine and the some aircraft, you still have to do that. Whereas, well, there used to be an engineer. Yeah, engineer. Yeah. Who I guess a lot of his attention would be taking up by there, engine instruments.

22:33

Yeah, which I think basically, there is one for each suck squeeze bang blow. Those dials all day and get everything kind of. Yes I want to talk about starting I mean well no it was just I was just a little sidetracked really. I mean, it's just, it is a, how do you start an engine light in a car?

22:50

You do it electrically. Yeah, you just can't get enough. Electrical power to start this air size of jet engines. I think some you can, so we have to use another engine, which is called the APU. Yeah. And that provides high pressure air. Yeah. Which will spin in the, the engine around basically.

23:05

And once it's spinning, a certain speed, you throw a bit of fuel in and hopefully it all lights up. Yeah. I think like like layman people like my family and friends sort of imagine that I've got like a set of keys like yeah on like a like you would a car.

23:19

Okay. So talk to that. What else do you use? Sort of the, the power from the engine for like, what else does it power in the aircraft. So it's an electrical generator. Yeah, set powers and all the electrical system. Yep. And it pressurizes hydraulic. Yep systems. Yep. And it provides high pressure air.

23:40

Yeah. For all sorts of uses pneumatic, new users, and air conditioning. Say, pressure the aircraft and keeping the air conditioned. And yes, a lot of accessories and engine eyes. Bleed air coming. Yes it. So, the point I'm getting out is, if, if you have an engine failure, haha, you normally get a lot of secondary problems.

24:03

Like some right, some hydraulics might not be powered you lose yet. One of your generators. So that's one of the things we don't see often in our career. But we do see a lot in the simulator. Yes, six months, we tend to get engine failures and a lot of associated systems.

24:19

Obviously, a twin engine aircraft. You've got two or four engines and so and we've got the APU which had just talked about exactly power unit which is like a mini jet engine really. Yeah. So that can provide some bleed air. Yep. And for accessories and electrical power yeah which is maybe how we power the electrics on the ground.

24:37

Yeah. All we can do and provide air conditioning on the ground. Yeah. And we don't want to run jet engines on the ground because the very hazardous yes, as in when we're understand and we're near people and things like that. But you can refuel and technically load bags and stuff with an engine running.

24:56

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Jet Engines as Hazards

Yeah. Yeah. But you wouldn't want to go anywhere near it. Well, my favourite videos from we're at university was I know you guys a guy on an aircraft carrier. Yeah, he got sucked into might be a harrier. Oh yeah. I think it was a harrier and he survived because his helmet.

25:09

Yeah, yeah. It's because it's so grainy. It's almost comical. But yeah, sadly. A lot of people have died and from being sucked into engines and that would be not just being sucked in and the exhaust velocity is really high. So you see people stood at the end of runways hanging on to fences.

25:27

Yeah maybe in some less well regulated airports where the threshold is really close to yeah people. But if a bit of the wrong bit of debris happened to be kicked up, that wouldn't, they wouldn't enjoy it quite so much. I didn't top gear had like a Virgin, 747, blown a car.

25:45

It flipped a car over there. Yeah. A car drove in the engineer sort of, yeah, whether it's max power or not. But yeah, literally flips the car over. It was that powerful and the bleed air which I don't think would ever really be hazardous but when they're testing engines, you know, the bleed air is kind of just not being used for anything.

26:02

I mean that's so powerful that would, you know, decapitate you, if you like, go anywhere near it definitely. So definitely hazardous and on the ground, obviously, when we're, when we're around them need to be careful about whether we're running them or not. They provide a lot of accessories, right?

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Systems

26:19

Well, and, and run a lot of systems. I'm sorry, they're very and when we have engine failures, we have to deal with the loss of those or yeah. Having only one system provide, I mean, typically one engine drives one hydraulic system, the other drives the other, but it's back up and there's a way transfer options.

26:37

Yeah. Yeah. And not redundancy, but the pilot. I mean, so what you're talking about earlier with how automated they are, typically you'd call it FADEC, full authority, digital engine control. Yeah. So yeah, you don't need a flight engineer because the pilot has a lever, I mean, in the airbus, it's just a toy.

26:58

It's not actually physically connected to the fuel valve or anything. You know, if we if we just go full power, all of a sudden we're not going to put too much fuel into the engine like you would on a and a simpler single engine piston aircraft.

27:15

We have to gently put the power up or anything like that. The FADEC takes care of everything. Yeah the FADEC detects problems to the engine. Yeah. And that's been around a long time. Feel like systems. Yeah. But now there's people in Derby, in Rolls Royce, in control, rooms monitoring all sorts of parameters.

27:34

I have no idea in the engine for the health and the engine and yeah, and and the life of the engine. Yeah, So there's a lot of instrumentation in the engine but as pilots, you know, we just we just need the engine to do so. Yeah. I think our probably our knowledge of engines is it's getting less and less because to us like you say it's just a lever that we move forward and backward and yeah, I don't know.

27:57

I find maybe some new partner newer pilots have less. Yeah, understanding of a FADEC or flight engineer used to do or, you know, because it's is simply just an engine. That you, I mean, sometimes practical stuff we know about would be like, how slowly are to spool up? Yeah.

28:15

Because we fly high, drag approaches one of the reasons being that the engines are about 50% already. So yeah, it's a shorter time to go to take off. Go around power if we need it. Yeah, but being aware of how long they take to spool up because it takes a while to build up that air flow through the engine.

28:32

Yeah, the position of the engine. So, typically, under slung engines on aircraft. We fly means that there's a pitch power couple but not in the airbus because it's fly by wire. So these are some of the more handling practical characteristics, that pilots are aware of literally using the thrust levers, the the failures so we could talk about actual engine failures.

28:54

Yeah. And I think has reverse thrust is sort of interesting as well. But that could be its own whole podcast. I think probably could do a whole podcast on with so exciting here yeah or deceleration or something like that. Yeah yeah yeah incorporate. So yeah we've you and I haven't had an engine failure but you'll be giving them out all the time in the sim.

29:15

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Engine Failure

Yeah. The one I'm the only thing is we practise engine fairly on takeoff, quite a lot. And I saw a generation of pilots favourite videos there, 757 at Manchester Thomson. Where has it? Like two herons going? Yeah. Right at rotation. That's like the classic engine failure at takeoff.

29:35

Yeah, profile that that we have to fly because it's a high risk and a statistically a lot of people fail it. So we have to keep practising it, but the one I'm scared of if you like, is the engine stall or surge? Yeah, because I think that would be one of the biggest startle factors of your career.

29:56

Yeah. So I used to do a bit of teaching on it and my understanding is that it's so loud and violent. Yeah, it might not be too much of a problem, but it's so loud and violent. But perhaps talking about that, just, I don't want to gave it to technical stuff too much more, but it basically would help you understand that the flow through the engine.

30:16

All nice and uniform and in one direction believe it or not. There's little era for y'all and compressor blades can stall like a wing stalls. Yeah. And you really shouldn't happen in modern jet engines. But if there's something wrong with the engine, maybe like a bird's gone down it or something like that the you can affect the uniform flow of the air and if the airflow stalls I it's not travelling the direction or the angle that you want it to you can then get a surge where the thrust the engine's actually coming out the front.

30:50

Yeah, but just in one little explosion. Yeah. So they can be really loud bangs. Lots of vibration. Yeah, that could be and I don't think we train that scenario, very much no. And I've think it would be terrifying. I've started doing a few in the simulator and it's actually really loud, right?

31:05

Okay. The effects of the simulator are quite quite good and quite loud. And it's, yeah, it's it's a good one to do because it's not what we expect. Yeah, we train very much because we know what I'm in the trees, or maybe in the climb or something. What we do, we have an engine failure, but you've got that initial startle to deal with.

31:22

Yeah. And there is on the airbus the engine install checklist which me the FADEC might detect or you might have to call for the QRH. Yeah. And and that just basically says reduce the power and yeah. Maybe live with it or maybe not and then that's an interesting situation.

31:38

Yeah. So, a lot of the these sometimes you see on online are people from the passenger windows you film in stores and where you get fireball, come out the front or the back of it. Yeah, but yeah, really loud, bang. So we were saying you'd be very unlucky to have an engine failure in your career.

31:58

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British Airways 09

What about if you could really looking you had four engine failures in in one day, I wonder what you're talking about. I think, you know, I'm talking about. So as we always do maybe looking at little case study yeah, little accident and there's obviously a lot of accidents out there attributed to engine failures.

32:17

And yeah, but be a British Airways 09 and also known as the Jakarta right incident, it wasn't accident where they had all four engines fail. I think that's probably a good one to I think, say, because like you say, I mean every other aviation accent has some kind of here.

32:41

Yeah. Like that. Yeah. And but it's about demonstrates about tying in, with learning about the engine, the engine and how it works. Exactly exactly. So, so very briefly then, so the background. So this was Boeing 747 flying to, I can't remember it was going to actually, but was again, all sorts because it was doing it from London to that multiple legs, wasn't it?

33:03

But eventually to Auckland, was it? Yeah, that's right. Yeah, I think this one was to Melbourne. Okay. And then it would go to Auckland and it is took off from Singapore. Is it on this leg? Yes, that's right. That's right. So flight crew, just flying along in the cruise night time there, sort of about a hundred miles southeast of Jakarta in Indonesia and they get an St Elmos fire.

33:25

I think is the first indication they get some St Elmos fire on the on the windshield. Those you that haven't heard of St Elmos fire. It's like little what looks like kind of static. Yes, that's all. She put your hands on. Yeah. And then your hair sticks, her hair sticks out.

33:39

Yeah. A little this that's St. Elmo. And then they started to get some smells in the cabin, a sulfury smoking a bit, sulphur smell. And then essentially, as they were, just trying to sort of figure out what was going on. The number four engine, I think failed, first, followed shortly after by the other three as they lost all four four engines.

34:56

So what was happening? What was going on? There's three of them because 747-200 flight engineer. Yeah. And Eric 40 minutes into the flight Eric moody, the captain is already gone back. Yeah. And decided to go downstairs to the toilet. He claims someone in the upstairs to it.

35:12

I think I thought the 747 maybe now the engineers not there and there's more room, but I thought it had a toilet in the flight deck, but maybe that the 400 anyway. So he's downstairs. And I think they call him back up initially, because it's the most amazing St Elmos fire ever seen.

35:27

On his is way back. He starts to see smoke coming through the floor ducts, okay, but people can still smoke in 1982. Yeah. June forth and but this doesn't look right. These scientists smell sulphur. By the time it gets in the flight deck, there's more smoke. Yeah, but it doesn't when he recalls it, he doesn't seem that panicked that recalling at that time that there might have had a fire.

35:52

He's like, well we had fire bottles in the cargo containers and we could have turned around Jakarta in 20 minutes and all this. So he sits in his seat and like you say, then an engine fails. Yeah, but the RB 211, which my granddad had something to do with, which it would have had four of, I think, right about this.

36:13

There was a different engine originally on the 747. Okay, not Rolls-Royce. Okay. And they failed like every other day, really? I think every, so these just consistently fail at top of descent anyway. Not not all four. No, one. So maybe the new and I there might be slightly less of a statle factor.

36:32

Like number fours failed. And like you said and it's St Elmos fire. So they're looking for the thunderstorm. Yeah. But there isn't one and then they are running the checklist. For number four shutting down with fire bottles potentially armed I think and then they are the rest of the engines fail.

36:50

Yeah. But the problem with Eric Moody is he is so chilled. Yeah. Can't get a sense of how they felt at that point. So unlike Chesney Sullenberger at 2,000 feet. Yeah. There at 37,000 feet. Yeah, so I think on the airbus you glide for about three miles per thousand feet.

37:11

Yep. And but then you are in the sea at that point? Yeah. I said they was starting to think they might ditch. Yeah, they had some, there's a mountains to make it over on the coast of Indonesia to get to Jakarta and it was a gamble to whether they would make it overtons and their decision was.

37:26

If they weren't gonna make it over the mountains, they would turn back to see and try and ditch in the sea. But yeah, I read something about you say about Eric Moody being really chilled out. His PA is like it got a title of like the most understated quote ever.

37:42

I mean, I haven't written down. Actually even remember it. It was something along the lines of ladies and gentlemen. All four engines have failed. We're working on it. I hope you comfortable listening. Hey there's our dinner. Damnedest. That's right. Okay I'm going again. I trust you're not in too much to stress.

38:01

Yeah and which apparently had quite a common effect. Yeah these are British Airways pilots and say well she spent there's a quite a few statements I think that were like very understated that they may that the crew made to each other throughout. And when Eric Moody talks about it it's all like tea and medals sort of just in a day's work.

38:22

Like yeah. Yeah. And I think one thing that em may be saved them. So if that's right, they had to put on their oxygen masks so we would do that for any smoke fire fumes. Yep. Because before you're overcome by maybe the fumes or the smoke you need to protect yourself.

38:42

Yeah. So they put on their oxygen masks and the first officers oxygen mass. The pipe. The pipe disconnected. You imagine Eric Moody and the engineer have a little discussion or all three of them decided to descend so that they can get oxygen. Yes you know they get them they're descending anyway because all four engine felt but they sped up there decent.

39:04

Yes. And they increase their rate of descent. Yeah. Directly breathable. Oxygen. Yes. So I tried a sort of find a bit more about that decision making process, but I think Eric had a little discussion about it because clearly all your energy is is in your altitude. So if you suddenly descend down to 10,000 feet.

39:21

Yeah, it's not got that long now until you ditch, but it's about dealing with the biggest threat at the time. And so the smoke in the flight deck and in the rest of the cabin was sort of like the biggest threat. So they decided to send down to 12,000.

39:37

So they could clear the smoke out the aircraft. Yeah. Because I'm guessing there what they would do is open like a Ram air system. Yeah, so I purge the, the smoke. Yeah, three, which is similar to what we do in any smoke situation, which is maybe prioritise the descent, but they still got no engines.

39:54

Yeah, however, once they are at a lower altitude. Yeah, I think their flying engine was busy trying to start these engines the whole time. One of them started up. Yeah. So they obviously had descended out of the hazard. Yeah. So maybe we should rewind. Well, yeah. What happens now is that when we didn't know?

40:13

Well, yeah. So now we can turn it relative to the jet engine and why the jet engine failed, right? So those of you that haven't sort of read about BA flight 9, it was actually a cash that they were in. They didn't know but their Mount Galunggung in. Indonesia had erupted, obviously couldn't see the volcanic ash at night time but that's why they were getting the St Elmos fire on the windscreen like ash particles basically hit.

40:41

Not the windscreen and becoming electricity, charged. I ionized particle. Yeah. And obviously volcanic ash going into the jet engine. So what happens to cause the so it's a unfortunate trick of nature that. Yeah you get these fine ash particles less than two millimetres come out of a volcano.

41:04

Don't show up on weather radar because they're too small no moisture either. Yeah. And they happily go down your jet engine, whether the temperature, if you remember, is, I don't know, 1400 or 1300 degrees. Yeah, which is exactly the right temperature to melt the silica, which is glass basically.

41:25

Yeah. So now you've got molting glass, which starts to melt and build up on the inside of the turbine where that temperature is and effect. Effectively choke the engine. Yeah. Until you get a stall surge which we described because you've got a breakdown of the flow through the engine.

41:45

You're basically choking it and just the ash can actually choke up. I think the compressor as well. Yeah, so that's what happened to the engine and also the bleed air system is taken in this, this ash cloud and we all know that volcanoes smell like sulphur I think hopefully.

42:03

And so they were smelling that in the flight deck with this with this smoke that they thought they had which is actually the ash particles. So, all the engines gave up. Yeah, and one more thing as well, I want to put out a mayday. So you're gonna aviate. So you're gonna keep the aircraft from stalling.

42:20

You'll start this later. then navigate. Yeah, we're gonna ditch, we can give the mountains, communicate power mayday. Well, if you're in a big ball of ionized particles, yeah, statically charged your radios. Probably don't work very well. No, but I think was a problem. They had then telling air traffic control but luckily somebody kindly relayed.

42:41

Yeah, their transmission. Yes. Or it was a breakdown in the fact that they couldn't believe that they were saying, well four. Yeah, I felt they thought there's a numbers. Yeah, there was a bit of that as well. I think a bit of communication language barrier as well, potentially, what possibly happened was they dropped out the bottom of this ash cloud.

42:59

Yep. And you've got loads of air going through the engine. Yeah, it's starting to cool down. The glass is starting to break off and fall out in the engines become clear. And then they just start back up. Let's start by locally. Yeah, and they all forced our back up.

43:11

And for one more number three, I think didn't like it, so they shut it down, they didn't touch it again. Yeah, so they got three engines now but at one point they thought if we just get one engine going. Yeah. Which again, if they thought they could, or they would just theorizing the 747

43:26

can fly on one engine only but just limp around the island. Yeah, not over the terrain about 12,000 feet. So quite high. Yeah, yeah. So that's what happened is that, right? Yeah, yeah. That's perfect. It's below. And also, some of these ashes abrasive. Some is less abrasive but either way it does damage the aircraft.

43:47

So you're so their windscreen had been attacked by their sun blasted effectively. Yeah. Which will come on to, in a second, I suppose. Yeah, I guess it's less relevant, isn't realised? Yeah. Engine. But they hadn't realised. And as they came down, they diverted into Jakarta onto it. It was a localised DME approach which was a bit unfortunate that they didn't have a.

44:07

Yeah, kind of nice. Simple IS, but yeah. And so the probably there's a clear night and they said oh what's the vis? And they said, like, you know, unlimited and they said no no, we can't see anything. Actually, it's is the windows. I hadn't turned the lights on either.

44:22

Maybe said, they'd and bothered to put the runway lights on, but anyway, he flew a lot. The eyeless stood up, I think. Yeah, yeah. I mean, imagine they're flying like, you know, an approach to the engine failure on a 200. It's a lot of rudder input and yeah, balance of the and that, but they weren't stressed out by any of that.

44:39

And then he so repeats that about 100 feet. He could do this little slit to the window that happened, not to be affected, he saw that, they were about the right place, so he just sat down and went, oh, we're not gonna die now. And then he just, they did like a really smooth touchdown.

44:55

It's not really. Yeah. And then they were left baffled for a while. Yeah, it took him a long time to figure out it was no time or volcanic and they call volcano he call it sometimes. Yeah, I think so. Is you and I had a, I've lived through. Yeah.

45:12

What do you call it? The 2012. It was no 2010 when he 10. Yeah, but not pronounced that volcanoes named Iceland. Yeah, that stopped air travel around from. Well, it was kind of transit from like Greenland across most of Europe. Yeah, basically but we used to read an ashtam every day basically.

45:36

Yeah. It was called that and yeah say that. Yeah, a 1982 and then plenty of aircraft are flown into ash clouds after that. Yeah. But at that point, I don't think the aviation industry knew that much. Well even some flew into that same ash clouds a couple days after oh yeah like that Singapore Singapore flight and had an engine failure.

45:59

Triple engine failure same sort of thing. So and only then did they close the estimate? Yeah, exactly. And yeah. So but yeah, it kind of the point of that, talk about that accident, is it? Incident is it emphasises the habitat? Engine works and how any little disruption to that airflow.

46:22

Yeah. You know, don't can cause it's fail. We have also checklist procedures for it now. Yeah. Volcanic ash. Yes. What would we do? I'm, I don't remember exactly, but the first line is basically 180 degrees. Yeah, I think I remember. Just get back out of it. Basically, remember what I was saying about, it's just unfortunate, the silicon melts at the temperature of maybe like a cruise power setting.

46:46

Yeah. And doesn't an idle power sensor. If you just go idle the turbine and temperatures drop low enough that you won't start melting the glass onto the inside. So maybe a 180 and a dissent idle descent and then put it on usually put on the bleed engine anti-systems because they provider a higher margin for the on surge.

47:10

Yeah, and situations and that's pretty much it. However, I say something we didn't mention is I think that unreliable speed as well. And what did they? How I didn't know that. Yeah, so obviously, the probes probes full of ashes. Well, yeah, say it makes sense. They had to realise the engines that to 270 knots or something and want it.

47:29

That's been indicated. 301 said 250. Wow. Yes, it hadn't reliable speed as well. And so I think the checklist that we have also guides you into potential and reliable or looking for a while. Yes. I think it does actually I do recall that. Yeah so but all in a day's work moody like just hope you're not too just you know was it.

47:49

Hope you're not you too much to stress the United stress. Yeah. We're just dealing with four engine failures and on reliable speed at the moment. When I first heard him, say that all four angels fell. I thought, what I say that, I just say, we've got problems. No problem with our engines.

48:04

I don't know. He's just like a bit of a character today. He's, I like him. He spoke it, thats before lots of different ways. Yeah. So lucky and then I guess David is slowly. Maybe learnt a lot from from that and then overreacted when the Icelandic volcano happened? Yeah, because I think they used like a nuclear fallout models, okay?

49:20

How particle spread. Okay. But they were maybe cautious though they weren't suitable or something like that and so they just grounded all. Aviation everything, go grand. They lie, this will gone from time. Yeah, yeah. And now and that time they theorize putting pods on aircraft and stuff to detect ash particles and things like that so you can find in them, but a lot of airlines fly in the shadow of volcanoes.

49:41

I mean we fly into Naples. Yeah. Sorry that's dormant, isn't it? And into call it sicily Sicily. Yeah. Okay. Name of the volcano. That's embarrassing. The airport of the volcano the airport. Yes. Anyway just escapes there's plenty of volcanoes around the world where including in Jakarta and you know what?

50:08

The most volcanic areas, the Pacific Rim, yeah, is basically the the line that all their aircraft travel on. Yeah. Fly around the Pacific. Yeah. Right over these volcanoes. 

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the end.

So maybe that was a introduction to the jet engine. Yeah I feel like we could do more maybe some. Yeah I think the practical stuff probably more interesting from us about how the pilot took you know things about the engine and but maybe you could do a whole podcast on your your childhood basically visiting Rolls-Royce because that's how it's interesting.

50:41

I just need to get engineers. Awesome. Yeah and I like you to go into the museum and you could the the dark which was one of the first jet engines was a turbo prop and you could touch the in the back of the engine. You put your hand in and you I put your finger on there, one of the turbine.

51:01

Yeah. Sections and move it with one finger and this giant propeller on the front. I mean, it's huge right? Would like move, you know? Feet. Yeah. Because even sat in this museum for years, it's so well engineered like without any oil in it. Yeah, you know, I mean and that's one of the that's like the first ever change in the Dart was like, really, really early on.

51:20

Yeah. So I don't know, if a pilot ever will be the person to do justice to a jet engine. Our job is to just take it for granted. Yeah, yeah. And let's yeah, literally moves a lever that makes it faster. Yeah. And I like the noise but that'll probably disappear as well gets.

51:40

Well, that's it for this one. Thanks for listening. Bye.

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