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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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Description

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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