Air Astana 1388
Posted by gromm93@reddit | flying | View on Reddit | 16 comments
So, I was catching up on Mayday (Air Crash Investigation to the Americans) today, and I came across the story of Air Astana flight 1388, where maintenance technicians installed a new aileron cabling system in an Embraer ERJ-190, and ended up reversing the aileron controls!
As a student, this very much drives home the checklist item "controls free and *correct*" as it's entirely possible that some mechanic has connected them all wrong. And checking the maintenance logs before flight to see what you should be watching out for in the first place.
But this seems like the kind of super-basic thing that airliner pilots are well past. I can understand that seeing the ailerons are difficult from the cabin, but... Still? Isn't this part of the pre-flight checklist after major maintenance? And isn't this driven home from the very earliest training onward?
In the accident investigation, it was found that the flight mechanics did a visual check of the control surfaces, and just didn't notice that it was all backwards. I can see how the point of view of the mechanic on the ground could be such that it wasn't quite obvious, even though the ERJ-190 has spoilers as well as ailerons for control through the horizontal axis, and they're supposed to work in unison.
Holes lining up in the Swiss cheese indeed! This should have been caught at many points along the chain.
Independent-Reveal86@reddit
I don’t know what can be seen from the cockpit of an E190, but don’t discount the fact that when you do a check 4-6 times a day, 4 days a week, 48 weeks a year, year after year after year, AND the check NEVER fails, you can get to the point where you’re not really checking anything anymore, you’re just going through a motion dictated by company policy.
ywgflyer@reddit
Our SOP on the E190 back when we had them was to have the flight control synoptic page up on one of the MFDs during the control check. If I recall, after they got on the ground, there was a photo of someone holding the yoke full one way and the synoptic was showing the ailerons the wrong way. So they would have had a chance to catch it if they had that page up. You can't easily see the ailerons from the flight deck.
On the 777 it's nice to have the cameras on the 300ER so you can see the ailerons with those. Usually the CA has the camera page up on the ground while taxiing.
Independent-Reveal86@reddit
On the A320 one pilot moves the controls full up, full down, full left, full right, while the other pilot calls out the position. It’s pretty easy to say the words without checking though, just like any other check, it’s only as good as the professionalism of the person doing it.
ywgflyer@reddit
Yeah, exactly.
On one of the older software versions on the E190 there was a nuisance EICAS caution that came up after the first engine start (I can't remember what it was). It became pretty common to see guys just cancel the caution without really looking at the display because it happened every time. One of the favorite tricks some of the instructors liked to play in the sim was to trigger something else and see how far guys would get before realizing they had a problem that you can't leave with. Lots took it into the air before realizing "hey wait what's this?".
Due-Letterhead6372@reddit
That is also a great example of how nuisance warnings can be dangerous
CashKeyboard@reddit
I've heard of a few carriers amending the Airbus SOP with the explicit order to do FCTL checks in a random order to prevent exactly that.
gromm93@reddit (OP)
The flight in question was a displacement flight post-maintenance. There were even maintenance engineers on board who actually knew what was replaced.
You'd think someone would check!
Independent-Reveal86@reddit
Yep, I know, the point still stands. Like it or not, there are people who pay lip service to procedures and checks and others who actually do them. The best of us get dragged in the wrong direction by repetition and constant reinforcement that the check isn’t really necessary.
The question I would ask is if they knew the flight controls had been pulled apart and reconnected. I’ve done post maintenance check flights before and took it as seriously as I could (I was never comfortable doing edge of the envelope stuff like stall warning and stick pusher tests) but if I didn’t know the flight controls had been pulled apart I MIGHT be guilty of treating the control check as more routine than it should be.
HardCorePawn@reddit
Indeed... the fact our SMS and the safety team are kept busy speaks volumes about how true this is.
Independent-Reveal86@reddit
Is it safe to start? How do I know? What if I’m wrong? 🤔
HardCorePawn@reddit
Touché
spacecadet2399@reddit
At some point, you have to trust that others are going to do their job properly too. There are a million ways maintenance could screw things up royally for the pilots if they do things incorrectly, and that we'd never be able to detect until it's too late. Ultimately, proper maintenance is just as important as any other part of aviation, and there are supposed to be checks and redundancies in place with maintenance procedures just like there are with pilot procedures.
I don't know what you can actually see from the E190 cockpit but in most airliners, you can't see the wings at all during a control check, and anyway what we're supposed to be looking at is what the instruments are telling us. I also don't know what the instruments would show if the controls were reversed in an E190. But we are taught to trust our instruments and if we start second-guessing them right from the get-go every flight, that's not going to end well for anybody. Again, maintenance just needs to be done properly and we have to be able to trust that that's happening. Everybody needs to follow their procedures.
Yes, it is a bit different than the world you're in right now. I was a private pilot before I was an airline pilot and there are a lot fewer checks and balances, legal requirements, regulations, procedures, etc. to keep you safe. Also, you can see your control surfaces in most small planes, and you don't necessarily have any instruments at all telling you what position they're in. And non-instrument rated private pilots are specifically taught *not* to rely on their instruments, so that's a different mentality to begin with.
But in the airline world, everybody has to follow their own procedures properly, and it is understood by everybody involved that if someone doesn't do that, bad things can happen. That's why so many redundancies and checks exist. Someone was supposed to check the work on those cables, I'm sure. I know about that accident but I'm not sure I watched that episode so I'm not sure what happened, but obviously some sort of maintenance procedure was not properly followed and the result was nothing good. I don't know if the pilots skipped over their own control checks or if the sensors were somehow fooled too by the position of the cables.
gromm93@reddit (OP)
Yup. This was, indeed, part of the problem! Maintenance came across an error message about the control surfaces (in particular: "FLT CTR NO DISPATCH") during testing, and it came up again and again. But I guess instead of calling out "ailerons right, ailerons left" over the radio for a visual check, the guy on the ground was just seeing "yeah, they're moving..." and gave up in frustration, actually replacing the control surface computers as a solution. This blanked the computer memory about how they're not dispatching, everything came up green, and "problem solved" in the maintenance logs.
And that also meant that no such error message came up during preflight.
At the same time, There were also three whole flight crew on board during preflight (plus 3 maintenance engineers!), and it's not a difficult task to send one of them outside to verify "and correct". Someone has to go outside to check for leaks and dents anyway. From a certain perspective, namely when you can see both spoilers and ailerons at the same time, it's really obvious. Someone did this during flight, which is how they caught on and, were able to recover some modicum of controlability.
I recognize that I'm 100% Monday morning quarterbacking on this, but it's also making me keenly aware about this, and every other checklist item. Which is a good thing.
minfremi@reddit
Always my worry when picking up a plane from heavy maintenance. Idk about the 190, but the EMB-145 doesn’t have control surface indication displays, and we can’t see the control surfaces from the flight deck.
The CRJ200, B-777, B787 all have the displays and I think it’s something Embraer should have implemented when making the 145 series.
ErmakDimon@reddit
I'm sure each and every one of us has had at least one flight control check where we weren't actually paying close attention to the flight control position.
Doing it hundreds and thousands of times over and over you just get used to everything being fine all the time. Add to that fatigue, potentially pressures for departing on time from an unfamiliar airport, etc etc and you get a good recipe of nobody in the flight deck noticing that something was off. Can't say I blame them, this could've happened to any of us.
rFlyingTower@reddit
This is a copy of the original post body for posterity:
So, I was catching up on Mayday (Air Crash Investigation to the Americans) today, and I came across the story of Air Astana flight 1388, where maintenance technicians installed a new aileron cabling system in an Embraer ERJ-190, and ended up reversing the aileron controls!
As a student, this very much drives home the checklist item "controls free and *correct*" as it's entirely possible that some mechanic has connected them all wrong. And checking the maintenance logs before flight to see what you should be watching out for in the first place.
But this seems like the kind of super-basic thing that airliner pilots are well past. I can understand that seeing the ailerons are difficult from the cabin, but... Still? Isn't this part of the pre-flight checklist after major maintenance? And isn't this driven home from the very earliest training onward?
In the accident investigation, it was found that the flight mechanics did a visual check of the control surfaces, and just didn't notice that it was all backwards. I can see how the point of view of the mechanic on the ground could be such that it wasn't quite obvious, even though the ERJ-190 has spoilers as well as ailerons for control through the horizontal axis, and they're supposed to work in unison.
Holes lining up in the Swiss cheese indeed! This should have been caught at many points along the chain.
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