Circling
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Circling Approaches. Circling approach use and risks.
Accident - Air China 129.
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Transcripts are approximate. Email us if you have any questions.
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.
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
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
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
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
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
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.
