Landing Gear
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Aircraft Landing Gear. Use and design. Landing gear failure.
Accident - LOT Polish Airlines Flight 16 - 767 Belly Landing
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00:00 Use and Problems
08:00 Large Landing Gear
12:48 Weight on Wheels Sensor
15:27 Walk Around
18:06 Nose Gear
22:18 Landing Gear Failures
24:46 Landing Gear Drag
26:55 Gear Limitations
31:27 Gear Pins
Transcripts are approximate. Email us if you have any questions.
Use and Problems
00:00
Adam Sam Landing Gear. Yeah, we do without them planes have landed without landing gear before either by mistake or by you know, being forced into it once you're airborne instead of like no use whatsoever. No. It's used for well taxing, the first 10 seconds of flight and the last 10 seconds of flight.
00:25
Other than that, it's just a draggy weight to carry around. Yeah, yeah. And takes a lot of space. Yeah, it takes a lot of space, I researched that it typically weighs about 5% of the aircraft weight which is quite a lot really for something that is crucial to the operation but for the actual amount you use it, I think getting around the airport you could do it without landing gear, you could invent something.
00:50
Planes take off without landing gear but I reckon you can't land and stop the plane that'll just be crazy. Yeah. Yeah. Agreed and like on a 380, like the impacts on like the shock absorbs and stuff can be up to like 391 metric tons. precise stays like a. Yeah, well yeah, that is a phenomenal.
01:11
Like, who's landings there that? Well, yeah, I don't know, but I, but they take an a crazy amount of yeah punishment. I've done some landings which definitely punish the landing care. All the landing should be sponsored by a Messier Dowty as much as we credit ourselves with the skill of the land in actually, the landing gear is making all the difference.
01:35
Yeah, in ways like, absorbing the shock and dampening in that out and so on and just taking the hard landings. And yeah, the landing gears. They're like the hidden genius in the landing manoeuvre. Yeah. So complicated there, it seems like the aircraft manufacturers kind of be bothered with it and they sub it out to you basically.
01:56
All I know, is messier dowty, who is messier dowty Bugatti, make all of them. Yeah. They I read there like the major player and I think this one or two others that the people amount of landing gear manufacturing. But yet there's not many companies out there like they've nailed it. Yeah.
02:13
And I was like, well just use that, we'll just use that. Yeah, then is the tires. And there's not many tire manufacturers. I don't think. And they're also pretty reliable, but when I was little, I used to watch Thunderbirds. Yeah, any came back to me this week, there's an episode where they go calling international rescue and I'm pretty sure it's an airliner, okay?
02:33
And one of the gears doesn't come down, right? So Thunderbirds come along and they drive underneath the plane. Okay. They happen to have like something machine, that's ready to and the pilot balances the wing on there on the side. Like, it's all in my memory. Yeah, I seem to remember that episode.
02:54
I'm about, I've watched like a hundred times and I was about five, but could technically do something like that and then you wouldn't have to have landing gear. Yeah. But, you know, and so we talks about it's it's heavy. It takes up space. A could there be an alternative?
03:09
I would say, out of all the minor technical problems I've had in my career when airborne and when flying not so much on the ground, a lot of them do so you seem to occur around like the landing gear or the brakes or really? Because I knows we're steering or, you know, I wake up in cold sweats thinking about the gear not coming down when I've got not very half an hour of fuel there.
03:30
Yeah, yeah, what have you had? I've had that sort of scenario coming into Malaga on tight on fuel because we've been holding and it been busy and it wasn't anything major. I can't remember. It's the exact problem. It was sort of problem with the brakes, basically, with the braking system, too much to process before landing.
03:50
So we ended up going around. And I think Malaga it's quite a long procedure to the mist approach point and then quite a long way back in. So we didn't have much time to sort of figure out what was wrong with it and make it go and approach. It also not find in the end, but yeah, I don't know.
04:05
I seems to recall probably like a disproportionate amount of you seem to be around the landing gear as well, which kind of makes sense because it's a huge moving part. Yeah. Of the aircraft that comes up and down every time, you know, big hydraulic forces on it. So the guys in listening to this from Messier Dowty like yeah.
04:23
Exactly. I mean it's impossible engineering. Yeah yeah the I think the flexible hoses that carry the hydraulic fluid in almost any airline is going to be hydraulically actuated. Yeah. Majority of the force on the landing gear, to push it down and pull it back up. There's like these flexible hoses that run the hydraulic fluid or probably to the brakes as well.
04:45
Yeah. They usually the culprits of loss of hydraulic fluid because all the hydraulic lines in the aircraft, a brilliant. But then the ones they have to dangle down fold backer over here, get hit by stuff, they're in the free stream, air different temperatures. And yeah so they are planning gears.
05:02
Gonna be responsible for a lots of hydraulics, which in turn might affect the landing gear. In the braking, anybody has had gear, not down. We do actually, we do. Yeah. Yeah. That was underneath, wasn't it? Yeah. And so pretty, pretty bad did sound pretty bad. They were, but even the gravity gear didn't solve it.
05:21
Yeah. The red light is sort of, the alternate system didn't work initially. Eventually it did. But we had in my previous airline an aircraft that took off when they took off all hell. Broke loose, couldn't engage your pilot, loads of ecams, okay, no automatics, no flight directors, gear and safe, kind of indication.
05:44
Some something leading towards that flew around manually had a helicopter police, helicopter film the gear, like they thought the news wheel was probably at 90 degrees on the 320, okay? Anyway landed safely layer on. But can you guess what? Caused all that mayhem. No, not really positive the LGCIU.
06:07
Yeah, yeah. So I was thinking about gear and I was thinking about the mechanical structure of it and how clever it is. But then the LGCIU the weight on wheel sensors. Basically controls linear gear basically yeah. And but also the computer controls the landing. Again they computer that tells the rest of the aircraft, whether it's on the ground or in flight.
06:28
Yeah, yeah. Makes that distinction. Yeah. Feeds into pretty much everything you can think of. Yeah. Imagine that like, they took off and the aircraft thought it was still on the ground and throw everything out on an airbus. Yeah. Everything. Well and all it was was a link rod.
06:46
Gear was bent slightly, right? And on the airbus, there's 36 way on wheel sensors, right? And one wasn't aligned. And that's enough for the airbus to be like, we're on the ground and gears. Not say even though the other 35. Yeah, that's incredible. Yeah, so all those sensors and I, you can see the weight on wheel sensor on the news gear, like quite easily.
07:07
Yeah. All that mechanical linkage is asked to all fold up and go up and down, and up and down. And if the aircraft thinks it's on the ground versus in the air, that's not good. You could have a lot of the systems name function. Yeah. Theoretically, you can't put the gear up on the ground.
07:26
No. Is it thinks it's on the ground because the aircraft needs a grounds on the ground. So, yeah. A big part of the landing gear is the electrical signals to the rest of plane. I think. Yeah. Which is a big part of here. I haven't thought about that but yeah, of course.
07:39
So yeah, I did. I just think overall we did get a pretty disproportionate amount of technical issues centred around, not just the gear, but the brakes and hydraulics, all around that, I've had some birds stuck in the landing gear and they, yeah, tire burst or anything. You've had I never had Thai burgers late but or deflate no but you do hear of that that does happen.
08:00
Large Landing Gear
We stop on our 330 fleet. You think of like bigger aircraft flying into like really well equipped airports but actually we're flying into a lot of old Russian runways in Cuba where you have to do 180 backtracks. Okay, on on 737s and 320s. It's dead by it, tight turn.
08:19
In fact, we drive out of stands and we turn the tiller wheel. And it's like a London, taxi cab, just like swings around. Yeah. But if you have multiple wheel bogies, if that's the right term, if you think about it, if you don't carry some forward momentum, yeah. You're scrubbing.
08:36
The tires? Yeah it's not one tire pivot in on it's axis, you're scrubbing. The tires literally you know like you're drifting in like some boy racer. Yeah, anyway, so we had instance where the tires would scrub at the 180 then the plane takes off and the wheel disintegrates on takeoff, right.
08:55
Okay. I know there's you know, famous like concorde for example accidents where the the tire debris and disintegration is caused they all crash. Yeah I think you know 380 whatever all big aircraft have video cameras, surveillance of landing gear help you taxi around and so on. I think also just to see how they're tracking along the ground and that you're not scrubbing them and stuff.
09:17
Yeah. See those. That the Antonov of yes. Like the answer of 225 or something. Right. I already got 32 wheels in 30 actual tires and I looked at a picture of like the layout, and it's just basically like a nose gear. And then the just two main gear with each with like 16 wheels on each side.
09:37
I mean, that's just keep adding more. They just keep adding more. Yeah, it's crazy the sort of layout of there, landing it. But that problem, you just described. Yeah, imagine that all 16 wheels just on one like bogey, one truck bogey. Yeah, I didn't really pay attention to any gear that much, but seven, four seven, as well as others, you know, has this incredible.
09:59
Got your main gear like kind of on the wingspar. Yeah. Then there's the two fuselage gear. Yeah. And then have you noticed that they're tilted? Yes. And the seven four. They're like vertical the, the main body one and then the wing one. Yeah, appar this say that they fit inside the aircraft when they fold up is that right?
10:22
All the tilted gears in the world it's because they have to tell to fit inside the fuselage because am I right thinking on the B767 they tilt forwards. Yeah. And the A350. They tilt forward. Yeah. And it's all about how they fit in fit and on the B777-300 of tail strike risk.
10:41
Yeah. When the pilots rotate, the rear gear gives them a little bump and that sounds ridiculous but it's held in a certain position so that it aids their rotations them off the runway rather than them continuing to pivot and scrape the tail. So that makes sense. That's interesting. Yeah, I didn't know.
11:01
It has an extra , what the piece is called, you know, that attaches those three or six tires yeah to keep it in a certain position which you won't see on the 777-200 and this and the concord that's where they were really worried about tail strike because of the, you know, angle of attack that it needed to fly at slow speed.
11:21
So it had a little wheel in the tail and which I didn't think you used. But in case it ever did tail strike that wheel would. It's not, you know, we all would take the impact rather than the tail strike. Yeah, of course, some aircraft won. The ones I've seen.
11:34
767 like a stick. This sticks out the back. Yes, tell you if you've done a tail strike, a concord just had a little wheel. Yeah. Yeah. So the gear is just like this crazy, jigsaw puzzle. Yeah it's a way. It's got to come down every time but also, it's got to nearly 200 miles an hour.
11:54
It's got to cushion. 200 tons or whatever. Yeah, yeah of whatever. Well you said whatever force it was. Yeah, well, 230, 400 tons on a 380. Yeah. But yeah, I mean, and I don't know if that's just a weight in the 380 but it could be more than that.
12:12
If it was a, I don't know where that figure is the actual impact. You know what the G, what the G would be. I imagine that's just the landing weight of a three. Like, I mean, the G like could be even bigger and at some point, it's somewhere. It's got to hit only one point of contact first, it's not going to just spread evenly overall, 22 wheels.
12:31
Oh yeah, I'm one tree. One wheel is gonna hit first which at which I guess the rest of the wheels will quickly. Follow soaking up wells, then start to until and then also that's where your LGCIU. Wait on wheel sensor comes in yes, you know, on the air bus when yeah.
Weight on Wheels Sensor
12:48
And what's the same on and once it senses partial touchdown, it will deploy spoilers for example to help everything sit down. I guess. So you're less. In fact, there was an accident where they greased on a 320 greased on meaning like they just really smooth touchdown. They did it so well that the weight on wheel sensors didn't detect that they were on the ground so they didn't get the spoilers.
13:15
So they didn't get auto break. Okay. And they may have got some reverse depending on I guess, what? They've I'm just trying to think through the, the deceleration logic but basically if you don't have weight on wheels that the logic of the deceleration, that's all automatic. Yeah. Doesn't start to occur.
13:34
So they had a landing overrun, right? The first officer died because he hit his head on the map light, which is in the spa between the windshield and the side window. Yeah. So on newer, airbus it's built in, isn't it? Yeah. On older air but you could pull it out and remove it around and they changed it.
13:54
Oh wow, because of that incident. So if you don't get wait on wheels, which could be through, for one of a better term, your own fault, basically, by maybe some kind of unstable approach or landing in conditions, you shouldn't be. But whatever is occurred, you don't get your deceleration is on, but the LGCIU or the fact that you've touched down is a big part of that say these landing gear as well, help you sit down on the runway.
14:19
Because once one is on. Yeah, I mean, some pilots always land. One wheel down first is like bit of a bad habit. Yeah, I've noticed that in a previous airline that was definitely a technique. Was like, if you just float in a long a little bit, they just dip the wing.
14:33
One way to get a wheel on, and then obviously, you get all the extra spoilers deploy and it helps so dumps and sits down to all the left and sit down here. But if you're on a 747, you might not want to try that because you get a pod scrape or even a 737 maybe where a bit lower down, when the engines are slung quite like, yeah, it's interesting.
14:52
It's quite like, yeah, it's quite love interesting things. It's what hey, what about? Wait on wheels now? NASA invented that like everything? Yeah, because when they touch down on the mean, you hear Buzz, say contact light? Oh yeah, yeah. So they had like a have we touched down sensor.
15:07
Yeah, on the LEM. Yeah. Wow. Yeah. They always invent everything because thinking about like a typical day, where the landing gear. The first time we approach it will be on our would be on our walk around. So the pilot flying generally, we're going to make an external inspection of the aircraft.
15:27
Walk Around
I always find the landing gear, the most interesting part, because the wheels are massive, and that's in a little airbus, they're huge like compared to a car tire, you know, they're they're incredible and they're rock. Solids 200 psi people always joke like you kick the tires but like, you hurt your foot, if you kick the tire, it's like get there, they're rock solid because they are thicker.
15:49
The idea is that once upon a time I don't know, on some US jet fighter, you kick the tires because you can't tell if it's deflated because the physical structure that's higher might maintain. See that's where it's supposed to do. Yeah. Yeah. They're like six times more inflated than a car tire.
16:06
Yeah. Yeah. They're filled with nitrogen. Actually. Yeah. So that it's, you know, it's more inert and all the temperature changes and stuff. I think less it. Go go to that. So so yeah we would you know, typically check the condition of the tire look for bold spots slightly, you mentioned earlier where you found anything in the tire.
16:26
Not found anything in the tire, but sometimes if you get like a bald spot, you see that like, webbing underneath like that white sort of webbing. That's generally the point of which I'd contacted an engineer for a worse. If people are always, I don't think there's anything ever written down as to when a wheel needs changing.
16:42
Well, there is but I mean for us as a pilot I don't ever been taught. That's that's a real change. That's not a oil change but they always say to me. That's fine. Yeah, basically yeah. He's a couple of grand for a tire. Yeah. Yeah. That lane like the cost of actually but they can change in like half an hour now.
17:02
Yeah, it's quite quick, pretty good. I live the aircraft up and not quite as quick as like formula one team. But like, they still pretty quick for the actual and they can do with passages on as well. I've I've had it done with passages on before as well. Maybe not.
17:15
Okay. Yeah. Maybe I can't remember. I always say to me that. Yeah. Because it will change. Yeah. Because they lift it any. A couple of centimeters off the ground. Sure. They have like a special like a formula aunty, right? Yeah slide. Just slides on and left it basically up.
17:30
Yeah. But they are like F1. I mean, they're like racing tires, because they, we're not, they're not designed for cornering. No, they don't have tread pattern, they just have a few couple of grooves in yeah. Yeah. But I've seen, you know, baggage tags and whatever FOD, that's lying around.
17:47
The apron can get so lodged in them space. You gotta look at stuff like that. Then obviously, we use some taxing around driving around on the ground. Generally, no problems there normally, but they, I mean, the. You can understand. Yeah. Yeah. They're not the grippiest thing.
Nose Gear
18:06
They're not grippiest. You have to be really careful in snow and icy conditions especially generally. When you're in snowy and icy conditions, runways have been cleared quite well but taxiways tend to not been attended to quite as well. So yeah, to get really slow because you think about you've only got even a 320 or 321.
18:22
So 60 70 tons aircraft. You only got three small points of contact on the ground. So in IC conditions. Yeah. You got to take it really, really carefully? Yeah, a space. Like your car, your average cars, sort of weight and balance even though the passengers changing a car licence and now, I feel like in an aircraft, you know, you could be totally empty, you could be full.
18:43
Yeah, the distribution. And so, yeah, it's not designed for like manoeuvring. It's just it's just a means of getting tip into the in balance episode. Yeah, in that. So a nice wheel. It's just a seesaw and the middle gear is like the pivot and the seal but you just hope that it's resting on the nose gear, just slightly on the nose gear.
19:04
But what about the news? Gear extension earlier extension? Do you like a bit of light? Do you look at that? Oh yeah. Sometimes or sometimes like so when you're disembarking you get oh yeah, get ground stuff, come up and say, you nose gears extenders. So you think about disembarking an aircraft generally passage at the front start getting off first.
19:25
So then all of a sudden all you wait is at the back with passages waiting to get off and the aircraft is slow very, very slowly starting to tip up. So I've had occasions where a ground can remember has come up and said your nose gear like oleo is massively extended.
19:42
As in it's almost is limit and it's about to start lifting the nose. We'll off the ground sort of thing. We used to get a tail tip message, didn't reach like advised you when it disinvert the back first, it's something made sure the bags have come off the bottom of the cargo, hold to the back first and see the air bridge, you'll find like the passengers.
20:02
Again, off last, I've got a big jump. Yes, from the aircraft. Yeah, because it's gone up by like a few inches but relating that to the gear. Yeah, you've got the oleo like like any bike now, really has like suspension. The earlier is nitrogen and that's right, isn't it?
20:19
Not just the tire and then fluid as well? Hi. So those combined create their, like we said earlier, they're dampening and the shock absorption. Well, it's my understanding. Oh, I couldn't pay any numbers on it. That the nose gear is not really designed for as much impact as like the main gear and even when you see it, it's not as big structurally.
20:41
You know. Yeah. The tires are generally but it's generally a steering aid. You hear very occasionally of people having like a wheelbarrow nose wheel first. Oh yeah. Because that causes it happened once in a previous airline to somebody they yeah they had a bad landing and ended up it knows we all touched down first and yet, of course, all sorts of problems.
21:01
Definitely, not designed to land on the news gear. Say, somehow that happens, yeah, you can have news gear collapse and you can have any gear collapse but that's having a few times or to come up through the yeah, the floor of the aircraft. Yeah, I think it happened to Southwest not that many years ago.
21:17
I'll ask you trainer on our little aircraft, the 320 at the moment. We don't fly the nose gear on to the runway. No. But in bigger aircraft to touch down the main gear. And there's quite a few seconds that go by before the and the deceleration starts. Yeah. And that and the and your deceleration and your you're breaking on the main gear can push the nose gear down too fast.
21:42
Yes you want to maybe reduce the the smash of the nose gear like into the runway. Yeah not keep the nose up for aerodynamic deceleration which I think a long time ago on some aircraft they were supposed to keep the nose gear up to have some kind of air dynamic deceleration something like that.
22:01
But yeah, fly the nose gear on and bigger aircraft. Yeah, I gentle nose gear turns down so you flares, not even over until well on the smaller. Aircraft, any tend to just let it smash that here. We can get on with the So what are the talk about malfunctions there?
22:18
Landing Gear Failures
You know, things that can go wrong with the nose gear and stuff? What are the problems? Have you heard of or either airborne or when you try and put the gear down? Or I mean your ultimate fear is the gear won't come down. So it's hydraulically actuated. So like all aircraft have some kind of backup system which is like gravity aided the gear should just fall down if you let it basically is is the way that it should work, is so heavy.
22:40
Yeah. So certainly on the airbus. It's like a gravity gear checklist. Yeah, essentially, just using the weight of the gear. It's not like that on every aircraft. Basically, the gravity should help it come down because the doors are kind of holding it up. Yeah. Or it's locked up in a way.
22:56
Yes. It's just a case of like, undoing. The pins basically that are holding. It has this hydraulically locked up above, 280 knots, or whatever, right? It could. Partially come down, the nose gear could come down, but be a 90 degrees, which is a specific thing that happened to a couple of airbus.
23:11
You could have a problem with one of the light bulbs. Yeah, it you for gears down and the gear is actually perfectly down. Yeah, we've talked about their weight on wheel sensors malfunctioning and causing problems. I think there is quite a lot. Yeah, I guess the point of making is there is quite a lot of things.
23:27
There's a lot of like moving parts and a lot of elements to the landing gear, but we practise, the landing gear gravity extension like quite yeah. Usually if company would like, hydraulic failure or something. Yeah, and all there's a whole checklist for it. It's pretty common sense, really? Yeah, but I've never done it.
23:44
But if you if you do that, you may or may not be able to retract it. So you can't just do that for a laugh. So if an aircraft lands with the landing gear doors open, it's really noticeable. Yes. Say just to state the obvious but just to make a point that the doors open, the gear comes down and then the doors closed.
24:07
Okay the doors on the on the seven four all big aircraft probably the same but they're they're like massive barn doors if you're gear doors are open. That's a massive amount of drag so they open and go away. Yeah. Also if you touch down with those down they might scrape the runway because they come down, come down quite low, but on air air, aircraft, a gravity or all, I guess, a gravity gear extension means that those doors open.
24:30
They then they don't fall away. Yes, there's no hydraulic assuming you've lost hydraulics but I did I did fly a seven five ones and we did a check flight and you'd all sort of stuff like depressurize, the aircraft and everything, but we did gravity extension, okay? But I think there's a maintenance way to, to reset.
24:46
Landing Gear Drag
I don't know if we talked about it on the windshear podcast but you know, through the landing gear doors. If you're trying to recover from a windshear, obviously, you know assuming like you the microburst is pushing you towards the ground but you would think oh gosh got this super draggy year like surely getting the gear up would help my situation but the reason we don't do that is because as soon as you try and put the gear up, the first thing that's gonna happen if the doors are gonna come down these big barn doors, they're gonna come down to allow the gates come up which is gonna increase your, your weight, your drag basically.
25:18
Yeah. So that's interesting fact, there's always stuck with me is to you know, why we don't do that? Because yeah, I mean the gear doors are huge. Well that leads us on to like what like do you ever use the gear for a? Yeah other purpose. Yeah, I was gonna ask you.
25:32
Exactly. Same question and I did it on my last flight. Yeah. So the gear can be a really useful aid on approach particularly or even on takeoff. So let's take off briefly sometimes people leave the gear down if you've got hot brakes. So if you need line to get down for a bit longer and like just a cold air, just going over them at sort of 200, mile an hour cools them down quite quickly.
25:54
It's quite noisy. But yeah, definitely more often or not on approach. So if you've been sort of shortcut maybe by air traffic control or you've, maybe mismanaged your approach slightly and you're getting a little bit higher, a little bit fast or just generally high energy, then gear is your friend, put the gear down and everything.
26:10
Just sort of nicely comes back to you slows. The aircraft right down helps if you descent rate because it is so. So big and draggy. But yeah, it's a bit like a glide slope from a above. Yeah. Something where you're trying to quickly catch the profile or something and you might want to be, we normally put the gear down so normally I mean yeah sort of five miles to landing 2,000 feet, maybe 1500 2,000 feet.
26:36
So as late as possible because of the amount of drag on fuel burn but early enough to ensure the aircraft and a stable condition to land it interesting things, I think one is, if you don't put the gear up on takeoff, it's the first call after lift off, is from the PM was to climb.
26:55
Gear Limitations
And then opposite road, you know, if I reckon tonight while I'm asleep, if you came in my room and went “positive, climb” I go. “Gear up”. Yeah, it's gonna be the number one motor function. However you've got the have to the after take-off checklist, but you can easily leave the gear down by mistake and start to exceed the speed limit.
27:18
You have the landing gear. Yes, even though it's incredibly noisy. Yeah. I think you'll start as you excited. You start to go? What is that noise? Yeah. And then you might go shit. The gear is down. Yeah. And suddenly throw it up, try to track it. But you actually going past the gear attract speed.
27:38
He said, how's that say, you can fly with the gear down up to 280 knots or something? Yeah, say on airbus? Yeah. If you want to retract it, how you've got to be like 50 knots flowers, 220 knots to retract the gear, why? Most of the doors? Yes, you rip the doors off.
27:54
If you go to well the motors that pull the gear up maybe is into the airflow? Yes, there was not powerful enough to do it. So you remember, when we did light aircraft training used to do a limitation operation indication? Yeah someone said flap when a single pilot you see when you want to move the flap or the gear.
28:12
Yeah. Then that's the little checklist. You'd run in your mind. Yeah. And we don't really do that on our fleet because we kind of do, but it's sort of built in on your speed. Tape is the flap. Yep. Limitation speeds. Yeah. But I stick with the limitation operating indication and I give a little placard next to the gear if I'm unsure.
28:33
Yeah. And then we will. Once took off from Manchester to do a couple of flight, four hours or something, and we had like a rudder ECAM or EICAS, I can't remember. And main maintenance said, we want you to come back into Manchester but we don't want you to land over-weight and you we can't dump fuel.
28:53
You don't want to dump your fuel on the peak district or anyway but on an unlike aircraft on the on A320. Yeah. So we flew around in the hold say to burn for quicker and put again. Yeah, of course. So then we want to go from the hole to final and we want everything to be nice and standard so we were like we'll put it back up but I just at the last second realise it sounds like I'm saving the day.
29:18
I happen to get something right on this day. I I I was like they were too fast for retraction. Yeah. Say yeah. Retraction speeds are quite limiting compared to L E. Yes, Is that right? No, Yeah, that's right. Yeah, with landing gear extended. So, yes, BLA. So landing gear operation.
29:40
So, like, with with the gear out, right? Sorry, and this is 280 on an Airbus and then VLE, the extension, the extension, which is 250 and then the retraction 220, he's 20. Yeah. So in emergency, we generally all the profile on the airbuses that we don't lower the gear because we get much higher to send and get down to breathable air quicker with the gear down but we'd have to slow down first.
30:05
So in order to get a gear down, exactly. And then that's gonna actually take longer than just then starting a descent and say gear attraction there you go like lots to talk about but also putting the gear down yeah just generally for burning more fuel or so you can use it to your advances sometimes.
30:24
Yeah you know it's a it's a, it's a draggy heavy. What about? And we've got a checklist for flights with landing gear, stuck down. Yeah. And it's not uncommon for a pilot to be asked for maintenance reasons, to fly position and aircraft not with passengers on, I wouldn't think.
30:40
But from A to B to like to, to lose for say that Messier. Dowty you can fix it. Yeah yeah exactly yeah. Maybe if it's have had a hard landing. In fact there was a news gear potentially a nose gear. First landing at Manchester and not in my airline, I think it was, it was in an airline, I'd flame four and they hadn't really reported it and then the aircraft took off and then they couldn't get the gear back up.
31:04
All right, so often the gears damage but it's okay because it's down. Yeah, maybe you can fly it anyway. Next. Try to move tractor. Yeah so you can get it to somewhere to be fixed with the gear down about landing gear pins. Yeah pins. So if aircraft are not gonna fly for a while, then engineers might install like lockout pins into the landing gear.
31:27
Gear Pins
So basically which locks it just stops and retraction gear attractions but yeah you need to make sure the engineers have taken those out before you take off. Do you just? Yeah, I always check and I tell you why I always check because once there was one left in, yeah, on an engineering flight you're like an empty, an empty flight and it was first officer.
31:49
My first officer doing his walk around noticed the nose gear pin was still and it was extra good. That he noticed that because there is always a pin in the nose gear. Anyway, which is like the steering pin for the ground crew to steer on the pushback and what's that?
32:02
Then so he so that that was their pin, but there was two pins, you know I'm saying? Oh, I see. So for for the ground crew, when they're pushing the aircraft back with a tug, they used. Like a nose wheel steering pin to essentially. Well, what's the number? What was a disconnect?
32:25
Yeah, it's disconnect. The nose steering wheel steering so they can steer it further so that we can't try. And and time the. But if they left that in and we took off. Yeah. Well, if we manage to take off, well, we’d never taxy. Yeah, you won't be able to steer.
32:40
So when they walk off with the tug, they're also waving the pain in the pain. Passengers should be able to see that. Yeah, so I don't I always say man with pin you toe bar or something. Yeah, but a pin is quite important. Although we have a memo on the aircraft or tellers, but you're saying, there's also an engineering pin, which is there to prevent gear retraction.
33:01
But I, I thought it was, I think I would easily spot one on the mainland gear because you never see it there. But on the nose we gear, when you do the walk around, you quite often, see the ground cruise steering pin, which is look, look, similar to the lockout pins.
33:16
I now I'm like, very conscious and I do check, is there all greasy there if you want to get horrible? Yeah, if you get them out of the little locket, like a little wardrobe that they're in, yeah, they won't cover in grease, but I yeah, if you don't do it, you'll never do it.
33:28
Practise makes permanent, basic here. You'll never do it and then that'll be the day. You were it. Guess you should be too big deal. You try and retract the gear, and it won't come up because it's just mega embarrassment. Probably embarrassment more than actual. Yeah. If you've if you really want, you can get a car key car key fob.
33:48
When you call it, this says removed before flight. Yeah. Yeah. On your bag or whatever. Yeah. Hang like a bag tag here which would also be for like the air data stuff. But yeah, that brings up about and in a nasal steering and maybe that's part of landing gear.
34:04
I'm not sure but we can steer the aircraft without the nose wheel steering potentially with differential. Breaking differential. Thrusts, but we use the nose wheel. We can use the tiller or the rudder pedals to stay on the. I mean, if you, if nobody's got that far into aviation, that's what the pedals are.
34:18
They're their brakes, differential, like, you can break the right pedal, left pedal, and you can steer with that's what you use there. The pedals for that. Sounds pretty obvious, but hey, I'm flying a light aircraft. This is quite embarrassing. Not feeling a lot aircraft for a long time. Don't have noise of staying.
34:34
Today they have a castor that does turn, but you actually influence it by breaking on the main gear. Yeah, I think so. Right? Yeah. Because yeah, I've, there's never a tiller. Yeah, you got. So you would put in the turn in the rod and the rotor, but I spend so long that I forgot there isn't actually nosebleed in there.
34:55
It just saw pivots around like they're trolley wheel. Yeah, yeah, yeah. How am accidents and incidents? So many. I mean this year there's there's loads, we we obviously we've chosen one particular probably a fairly recent one to talk about but I mean, yeah, this this heat, there's loads and I remember what you videos of loads of it was like a virgin seven four landed at Gatwick a few years ago with it was missing.
35:23
LOT Flight 16 Belly Landing
The left main gear didn't come down so it had like it's right main gear, the nose gear and those two fuselage gears so it kind of landed. Okay. And it never tips but it was it was like a bit. What it looks about wonky on this. Slight video. Remember watching that with my captain at the time.
35:42
He was on the 747 and he went or you'll be embarrassed by that because he saw bounces it. Oh, right. Okay. You obviously won't like this me this one. I'm sure the guy did an amazing job and yeah, a lot of these incidents or maybe accidents like Sioux City.
35:58
Yeah. The media of all turned up in advance. Yeah. Yeah. It has the pilots usually know. They've got a problem. Yeah. And then going to a very long troubles, a thing why? Which time all the media, tenants the runway. Yeah watch. Yeah. So yeah blue. Yes. 320 where the nose gear is at 90 degrees to the direction.
36:17
You should be. Yeah. Even the passengers on board is JetBlue. Such a fancy airline. We're watching the live footage of their landing. Yeah. From a helicopter, news, helicopter from their seats. That's like some kind of like weird, like inception. Like yeah, yeah. Watching yourself land from a television. But it's funny because pretty much all fleets apart from us.
36:40
You can this cameras on the gear and stuff say see would be able to see and probably turn them off if I was a captain. Yeah, no problem. You don't want to watch this but and the one we gonna talk about was the Lot. Polish airlines 767 Flight 16 back in 2011 november the first nearly 10 years.
37:01
Okay, basics of the flight is yeah. 767 flying from Newark in to Warsaw in Poland. So quite a long flight that piece of eight hours, probably nine hour flight time, I would have guessed. So I had a hydraulics problem after takeoff shortly after leaving New York and my first question to you, you know, for the benefit the listener would be so.
37:27
Okay. So they had this problem with hydraulics, after takeoff, not a major problem but they continue. Let's continue to go to carry on to wars or nine hours. Why as a pilot, would you do that? What I'm not saying that's what you would do, but why could a pilot?
37:41
Why could you potentially continue the whole flight? Well, the complication there is that they're going across the ocean into a, quite a remote situation with only two engines. So they have an e-tops extended, twin operations rules, which is like more stringent. So if they're just flying across the states, you know, from east coast to west coast or something, be even as even more of a different question.
38:04
So the fact that they went all the way over the Atlantic with only two out of the three hydraulic systems is a more interesting question. When you and I were at uni, I remember reading British Airways 747 took off. I think from New York wasn't then lost an engine and one of the four engines, but went all the way back to LHR.
38:26
It didn't make it heathrow, but nearly did, but it diverted in Ireland. So why? Yeah. And I think, yeah. And I think the Americans were a bit annoyed. Yeah. But the British were like, well it's totally within the ruleset. Yeah. By the Americans a bit more. Like obviously, you would just go back to the airport like, why they were, you know, what I mean?
38:45
Say that it made me think about that. I don't know what I do. I did used to fly 767 and over the ocean, but they didn't definitely have to return and I don't I'm not sure. They knew exactly the extent of the problem at the time. I do know.
39:02
There is what we talked about. It was a hydraulic flexible hose on the gear. Yeah. Which was like, a bit twisted over the years had just given and you know the thought process could have been. Well, this is only going to cause a problem on landing and we have to land somewhere.
39:19
So well, why not at home and spend the next hours. Next nine hours sort of prepping for it essentially. Yeah. I guess. So, what I'm saying is you can't well, you know, we went there, so we don't know the full extent, well if I, but it's not on unbelievable decision to carry on to warsaw.
39:38
So when you, when you've only So the idea of having three redundant systems, you know, is important, especially when you're flying over a remote region or over the ocean. So, knowingly, going over with only two. Although I confess, I don't know if it was a total loss of a hydraulic system at that stage.
39:58
But anyway, yeah. I don't know what we transfer the question. No, no. The question was just like, why could you continue? Well, I had a, yeah, I mean, I had a, I've had a total hydraulic loss and you just quite, you know, quite often thing. Well could divert, but it's only gonna be a problem on landing somewhere.
40:17
So sometimes you know there could be arguement for carrying on to also. Okay, so then they got to wars or eventually attempted an approach and that was when they really knew the extent of their of the problem of the hydraulics failure because the gear wouldn't come down. Well, it can get the gear down to think not to say that you got that wrong, but they knew it would have to be like an alternate gear extension.
40:48
Okay. Okay. Yes, they lost the heavy system, okay? Yeah. Fair enough. Yeah. But they, or they lost part of their system that uses but the alternate gear system that they were expecting to work on final approach didn't work. Yeah. So then this is yeah. Why is that related? You know.
41:05
Yeah, there's they they must have done a lot of think ahead. So okay we're gonna and we've lost a hydraulic system. What are the consequences for the flight? You know the cruise the approach? The land in the rollout? Yeah. And one of them was okay, the gear won't come down but we use what we call gravity.
41:24
Gear, extension. Alternate, great extension or something. On the 76 electric motor isn't it? Like is the a lot of the lock is. Yes, so that's kind of important to the story. So on our aircraft, it doesn't work like this. Once you open the hydraulic lock, the gear falls down.
41:37
Yeah. On the 767. There is an electric lock. Yeah, which has to be moved. Yeah and it's really important that that lot can be moved. So it's attached to like a battery bus that would function even in. Basically a total electrical failure you would still have access to that to get the gear down.
41:56
So no problem, but that didn't work, the alternate gear. So they ended up doing a go around and then exactly as you described, they held them for an hour trying to figure out like, what really has gone wrong here by which point everybody is alerted to the fact that this aircraft come in fact, I've even sure that I remember hearing it on the news before it actually left before the aircraft had actually landed.
42:21
I'm sure I got like a news update or something saying, there's a lot 767 with a landing gear about to make an emergency landing in Warsaw, so they evacuate the airport. I think close all the roads around the airport, setting up two fighter jets to go and have a look, you know, trying to get a look at the lots of the pilots near the gears not down, like it can hear it?
42:44
Yeah. But I guess they're looking for light is it's kind of stuck half down like any sort of information. And if you've listened to the oxygen episode, like we know how close like fighter jets will. Yeah, and probably Polish fighting yet. They're probably, like, stick hand out around out of wiggle.
43:01
Like, yeah, trying it down. So why jets site kind of went up to have a look at it but imagine you've done your 11 hours over the ocean. Probably even had like nice sleep controlled rest. Yeah. You just think you're gonna be filling in a minor ASR about a hydraulic loss or something and a minor report about a holly a hydraulic loss but that moment the gear didn't come down on your backup option.
43:27
You then started. I think that would have been shock and start all moment of like what have we misunderstood definitely how is that related? The gear should have come down. So every aircraft you're looking at has a way to put the gear down but there's always a backup option which basically means it will always come down.
43:45
Yeah, right. Yeah, even if you've lost all your fuel, all your hydraulic fluid, or your electrical systems, the gear is it's like him. So the the risks involved in a gear up, landing are really high, so it's like a system that has to the risk of it. Not coming down has to be like as close to zero as possible but there is a checklist for a gear up landing.
44:07
But I see that as more of like a team building exercise to distract you from. Yeah, your imminent catastrophic actually it's like the bomb on board checklist. I'm like this is just to distract you while. Yes, you don't sit and think about what's actually gonna happen. Yeah, I don't think it's of any use but that's not true.
44:28
I mean, partial gear extension and stuff, like very survivable but there's some bad examples of them as well. So just to be clear about this. There's no way in anybody's mind that the gear is not going to come down. And then all of a sudden, it doesn't come down now and we always talk about Swiss cheese and you know, holes in Swiss cheese lining up.
44:48
Yeah, you know, here you go. So there was a hydraulic failure, but that shouldn't mean an accident. It's funny. The Swiss cheese just one because there's not that many layers, but the two holes are like tiny, but they just perfectly lined up like, yeah, you know, it's not a matte, it's not lots of layers of Swiss cheese.
45:08
It's only really two kind of layers, but they're just like perfectly aligned. So we know about one hole so it's gonna hydrate failure, no big deal. Yeah. Say the pilots have gone to go into a whole troubleshoot and and come to the realisation that the gear is not gonna come down.
45:23
So want to perform the gear up landing checklist, which will tell them to do with this little fuel as possible. Yeah. Because obviously you then start to land on the structure of the aircraft and the only thing between you and the runway then is the skin of the aircraft and the fuel tanks are full of fuel.
45:40
Yeah. Say you don't really want fuel spilling out while you're sliding down the road. Am I right in thinking that whilst this was going on while they're holding for an hour that the pole? They're like also airport the poles like put some special stuff on the wrong way. Yeah, and they can do that everywhere.
45:56
They phone their own way, and I think it actually works as well to prevent fire. I think it's not just like another team building like, didn't worry like that. We've found the wrong way. Like you become party. Yeah. No. It's actually a fire retardant. You know idea? Yeah. I have a lot of fame, ready.
46:15
I'm just gonna say same around my favourite runway. I guess the managed to fame, probably like the most important bits of it. Yeah. And so yeah, they're gonna have to do a gear up landing. The one they, there's never thought they'd have today exposed to, in the back of the mind.
46:32
They got me thinking, how is this possible? But I guess they, in the end just thing, it's just not our day. Yeah, and the runway's phone, the airports have accurated, the roads are evacuated, there's not much fuel left in the tanks. The cabin crew have got time to prepare for it, the pilots the ground.
46:50
There's some what they made services are probably be thinking ahead. Yeah. It's almost, you know, if it planned. Yeah, yeah, yeah. It's like what you see, almost became. It's like we're gonna crash. Yeah, everyone ready? Yeah. Yeah. We've got an hour to sort it out. Yeah. Yeah. How long they had, which they're lucky because they continued all the way to Warsaw.
47:12
Yeah, and still had a bit of fuel to sort of stuff out. So what happens next? Well, by all accounts, like they kept in and the crew did like an amazing job of like this. Perfect gear up, landing hundred percent, everybody, survived minor. If any injuries everybody walks away basis.
47:33
How to evacuate as a matter of proportion? Evacuating any aircraft? Let laying with 300 people on? Yeah, you might get a death because you throw in all sorts of different people down. Slides in a panic. Yeah, of course. But no, that was fine. One of the engines caught fire but don't worry the fire service were there.
47:52
So please put it out straight away. Initially like the guys were like hailed his heroes and I mean they did do an amazing job but there was like a little tinged here to the heroism discovered later on which was the reason why the alternate gear didn't work which was the circuit breaker.
48:12
Yeah. On the battery bus that has a couple of important things connected to, yeah. That circuit breaker was pulled that circuit breaker was popped pulled up up to you. Exactly. Yeah. That circuit breaker was out. Yes, which means that it's like you've unplugged those systems. Yeah. From the mains basically.
48:33
Yeah. And I don't think we ever really know why it was out whether it popped, or whether there was a, there was a suggestion that because it was next to one of the crew bags that a bag, you know, being slated into place had like popped it. I pulled it out by accident.
48:50
Yeah. So I think my understand is more than like a suggestion. It's like that is what happened, that's what happened. So they know for a fact that it there was no electrical failures that cause that circuit breaker to pop. So, in the flight deck, you've got a panel of circuit breakers and when their passengers come in to have a look around and they look at all the switches, they often look at the circuit breakers and go, oh my god, all the buttons.
49:14
How do you know what what they all do? They're not buttons. It's just like a fuse box at home, right? Yeah. And I can't remember about the seven six not but on our aircraft if one of them pops the ecamel tell you. Yes. And if it's, if it is a monitored, what colour is a monitor, lizard green.
49:35
Yeah. So it's a green circuit breaker. It means it's monitored. Yeah. It's music. E-cam will tell you, if one of them spots, any will tell you, like, look on this row and then you can see that that it's popped. And I guess the seven six doesn't have that. No, but yeah, when I feel, I was a first officer and right by your flight back, basically, and where you sort of walk into the sea.
49:58
Okay, there's a little wall of circuit breakers. Some of the most important circuit breakers. Yeah. That never probably the most important ones. So, somebody designed the aircraft and somebody decided to put them there, yeah, Boeing sold and optional extra which was a cover for that that particular panel, right?
50:20
Say that you couldn't accidentally knock them because it happened on loads of different aircraft already. Before this accident, these guys were just unlucky that it happened as well as failure. And essentially, they lost both mechanisms of low in the gear, That, that circuit breaker was kind of like damaged.
50:40
Like it'd been knocked. I probably more than once in its lifetime, Right? Right Bear. In mind, that while they're troubleshooting they're on the radio to, you know, maintenance operations. Yeah. And they gave them five different like maintenance kind of fixers. This is definitely going to work and including a circuit breaker for the alternate gear extension, Right?
51:05
Which is called like F1 or something. Then and there were like, all you got to do, is reset that. Yeah. And I think the FO did it like seven times. Wow. So, bear in mind that the flight crew at some point, probably the first officer is knocked, this circuit breaker because it, it was, would have been in before takeoff.
51:24
Yep, right. But the whole of lot airlines possibly even going on the end of the radio, couldn't figure out that it was that yeah. Boeing knew about this problem, but hadn't had designed the aircraft that way. Then knew about the problem, then some then offered a fix to people, but didn't enforce it and maybe even the regulators knew so were the pilots heroes as the media might say or you suggested.
51:52
Yeah. But where they like these antiheroes when you found out they were actually caused the, the last layer of the Swiss cheese. Well, no, because not one person on that day. No, came up with the idea of. Why have you just not here with your flight bag like? Yeah, right.
52:08
But imagine that writing off an aircraft in a belly up, land in down a runway and it's a tiny little circuit breaker. It was characters as a whole loss was there. Like, yeah, they wrote it off right now but a Polish prime minister rightly gave them like oh yeah, awards and they are and they are heroes and massively.
52:26
If you can understand that you might be that first officer one day. Yeah. And he does the most stupid thing in hindsight. Yeah. But does everything else according to their training and procedures? Absolutely perfectly and goes beyond then. Yeah, then you'll understand like the nature of the nature of aircraft accidents.
52:46
And when I started flying, the seven six seven. That's the first thing they told me. Yeah, don't knock that with. You fly back because you remember the lot thing and I was like, oh, right? Yeah, so I'm not gonna make that mistake. No thanks to those guys. Those guys you made who paid not the ultimate price, but managed to show how good they're their skills are.
53:08
Yeah, again like more evidence. We say, every time of just learning we learn so much from other aircraft accidents but we like to learn proactively from you know, occurrences and incidents say yep. Boeing should have put out a thing. Should have put a sticker in front of the FA saying, did you just knock that when you guy in the seat, just have a check or something like should even be on like the gear checklist?
53:30
Like the well, they get in the QRH like check CB I'm sure I'm sure is now this podcast isn't about circuit breakers but do you if you have a failure? Yeah, and you run three the ecam. You might do a bit of thinking outside the box, you might consult the manuals called main troll.
53:50
Do you personally are in your checklist, think? I'll just turn around and check the circuit breaker probably not. By not religiously. No. Say yeah we're not expected to you know we don't have I had a little fire basically in the flight deck and the on the checklist it says isolate faulty equipment.
54:10
Yeah. So as I wears the with, how do I isolate the printer? Yeah, and I went through the every row and then, it says PTR SPY, which I guess means still to this day I guess it means printer supply. Yeah, I was like well I'll pull that. Then try that but we don't have a list of the CBs and we're not that's not part of our chatlist to check them so the landing gear and was functioning perfectly that day.
54:37
Yeah, I guess the crew demonstrated how important they're landing gear is yeah. And and how you can pull off it and they're landing without the gear. Yeah, but in hindsight was preventable. Yeah, gets really interesting. I think that's it. Cool, yes. Bye.
