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The crash of Air France flight 447 (2021)

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Re: The crash of Air France flight 447 (2021)

#211

Post by wkat4242 »

jcalvinowens wrote: post #146
wkat4242 wrote: post #139

Earlier quoted context omitted.

It's a really long and clear paragraph, what more do you expect? The summary blames the accident on poor training and the typical EFIS "pilot out of the loop" problem, rather than very specific issues like this. Which makes very much sense IMO.

He spends a lot more time shitting on the pilot then he does talking about this, that's backwards IMHO.

He doesn't really shit on the pilot IMO. He clearly states that the pilot was a product of his generation and mindset and far from the only one. He clearly states it's more of a systemic failure than an individual one.

And this is only part of the many things that went wrong. Also it's important to realize the system worked as designed and in every other situation this behaviour would be beneficial. I don't think this was even changed after the accident.

As one of the other things that contributed, the pilot should never have got into this situation in the first place. Which is explained by the poor stall training focusing only on low altitude stalls (which makes sense as this is by far the most likely time for them to occur, but the difference with high altitude should of course be explained as it is being done now.

As with any major incident it's a matter of multiple errors compounding in just the worst way possible.

Re: The crash of Air France flight 447 (2021)

#212

Post by marvin »

jandrese wrote: post #99
psunavy03 wrote: post #46

I fly a desk herding cats, I mean devs, for a living now. But as a Navy-trained aviator, this and the Colgan Air mishap in Buffalo always make me cringe. I can't entirely judge the crew, because the human mind is a strange thing that has ways of rationalizing truly abnormal situations and behavior. That said, an obvious Crew Resource Management failure compounded the issues here. That said, I believe aerobatics and o…

Maybe not even acrobatic flying training but glider training. Pilots with glider experience are some of the best performers in emergencies.

You certainly learn to pay attention to the aerodynamics. Lots and lots and lots of high-bank turns. Many of them relatively low and close to stalling speed.

Some occasionally below stalling speed, if you're high enough to safely reduce margins so much that a gust of tailwind puts you below, which requires you to just calmly follow through with constant angle of attack, descending, rather than force the nose up.

Short-field landings in unfamiliar places, requiring judgements of both approach angle and terrain. Moderate to heavy turbulence all day, speed varying from stalling to redline. Retractable landing gear. Flaps if you want that source of mental load too, in all speed regimes. Constant consideration of wind. One shot landings. Mountain flying with constant consideration of where the safe exit is. Consideration of deteriorating weather. Always aware of nearest landing site.

It's really non-stop training in all the fundamental parts of flying, minus engine operation, airspace and ATC communication.

Re: The crash of Air France flight 447 (2021)

#213

Post by mardifoufs »

_cenw wrote: post #207
mardifoufs wrote: post #195

Earlier quoted context omitted.

No, some warnings were also thrown away and never shown to the pilots because the automated systems thought they were erroneous (since they were so outside the flight envelope IIRC).

If by warning you mean the audible stall warning - that's because below 50 knots, the airspeed is considered unreliable / erroneous, because to get to that speed without flaps you'd have to be stalling the aircraft for over a minute (getting that exact warning) and surely nobody would manage to do that... As I said elsewhere, the airplane was quite literally falling as fast as it was moving forward. I don't really fa…

Actually, you are right. I think I either got confused with another crash or thought it was more than just the audible stall warning.

And I totally agree, there's no good solution to helping the pilots in such a catastrophic situation. They were probably going to ignore audible warnings and most visual cues anyways, considering how tunnel visioned they were from the moment the auto pilot gave back the controls to the pilots.

Re: The crash of Air France flight 447 (2021)

#214

Post by rich_sasha »

davidktr wrote: post #199
rich_sasha wrote: post #182

As someone who follows aviation and flew the Flight Simulator quite a bit when young, I don't quite understand how it all happened. The mechanics are clear, but aren't pilots trained _ad nauseam_ precisely against this kind of events? It read like this was two panicking guys shouting at each other. By contrast, listening to the recording of the Hudson River landing, it was stunning just how eerily calm the pilots was…

If you have an hour to spare, I found this video by an experienced pilot extremely helpful: https://www.youtube.com/watch?v=e5AGHEUxLME

You're right, a great video, thanks for the top tip.

If nothing else, it provides complexity to the situation, which I felt was somewhat missing from the article.

Re: The crash of Air France flight 447 (2021)

#215

Post by kikokikokiko »

jstarfish wrote: post #183
kikokikokiko wrote: post #112

Earlier quoted context omitted.

I have zero flying experience, but man, just by playing Pilotwings on the SNES and Ace Combat on the PSX, it's ingrained in me that when you stall any aircraft, be it a hang glider or a fighter jet, you put your nose down, gain speed and recover your aircraft. I am Brazilian, and since the first time I read the accident report I couldn't believe how a professional pilot could keep pitching the nose up for minutes on…

My lack of credentials are identical to yours (fuck Lance) but this is way too harsh. When you witness a car veer off the side of the road, "what a moron, why didn't they just turn the wheel" is a logical question, but in reality the driver may have thought to do so and been physically unable to correct a power steering failure in time. The SNES controller had 8 buttons and was operated from the safety of your couch.…

All of your arguments are pretty valid, but still it DOES NOT excuse Bonin for keeping the damn joystick pointing the nose UP for MINUTES on end. At some point in time you must reflect upon what you are doing. If my hypothetical car needed to do a turn right, and I keep pointing the steering wheel left for many minutes and still do not realize that what I am doing is antithetical to what I want to happen, the blame is on me. I place the blame for this accident 75% on the crew, and 25% on the stupid design decisions made by Airbus. Averaging control inputs is an inexcusable design decision, and not mechanically linking the controls is the cherry on top. If those 2 design decicions weren't made, hundreds of lives wouldn't have been lost that day, even with the amazing level of incompetence shown by Bonin et all. And every Airbus flying nowadays still have this fatal flaw.

Re: The crash of Air France flight 447 (2021)

#216

Post by twelve40 »

jimmaswell wrote: post #162
mrguyorama wrote: post #82

Earlier quoted context omitted.

The reality is there is not a single thing you can legislate or train that will prevent a pilot from flying a perfectly working plane into the ground if they get stubborn. Aircraft emergencies are all about keeping you out of panic so that your natural instincts don't surface, because pretty much every natural or intrinsic human instinct, if followed, will just result in you flying the plane into the ground. Every se…

> The only fix in this case would have been literally evicting that pilot from the cockpit, and there's no button for that. Military jets have such a button. Maybe commercial needs to take some inspiration?

what, an ejector to parachute the pilots, fuck the passengers? that would be pretty funny. It does save the airline pilot replacement training though. Or maybe an ejector to throw just the bad pilot out?

Re: The crash of Air France flight 447 (2021)

#217

Post by brohee »

IMHO something is still missing. Bonin's father was a pilot (in Air France AFAIK) and I can't help but think the likelihood he was the best candidate was low, but that legacy played a part.

I also wonder if he had much passion for flying or was just following his father footsteps. I wish they would value passion more, easily demonstrated with military/glider (I must miss some..) experience.

Re: The crash of Air France flight 447 (2021)

#218

Post by Mawr »

mrguyorama wrote: post #92
dabluecaboose wrote: post #60

Earlier quoted context omitted.

Yeah, I guess as someone who's had minimal instruction it seemed obvious. But reading the article it's clear that the junior FO was trained basically exclusively on the fly-by-wire Airbuses and probably didn't have that intuitive understanding when that protection was stripped away.

The plane in this case doesn't matter. No training for stalls ever tells you to pull up. It's directly opposed to how stalls ARE trained. This pilot was a chaos monkey, and the other pilots were unable or unwilling to get the chaos monkey out of the situation. He had completely reverted to human instinct, which is terrible for flying, and also was letting himself override his copilot, who was handling the situation m…

With linked controls the captain would have instantly been able to tell what inputs the copilot was making and could have taken appropriate actions.

Aircraft UX should be made in such a way that there's never the slightest of doubts about something as fundamental to its function as where the inputs that its using are coming from.

Re: The crash of Air France flight 447 (2021)

#219

Post by jimmaswell »

twelve40 wrote: post #216
jimmaswell wrote: post #162

Earlier quoted context omitted.

> The only fix in this case would have been literally evicting that pilot from the cockpit, and there's no button for that. Military jets have such a button. Maybe commercial needs to take some inspiration?

what, an ejector to parachute the pilots, fuck the passengers? that would be pretty funny. It does save the airline pilot replacement training though. Or maybe an ejector to throw just the bad pilot out?

Just the bad pilot is what I had in mind

Re: The crash of Air France flight 447 (2021)

#220

Post by dreamcompiler »

thatswrong0 wrote: post #136
dreamcompiler wrote: post #133

I'm amazed that the autopilot kicked off just because the pitot tubes froze. The A330 has an inertial reference unit as well as (almost certainly) GPS, both of which could have provided ground speed. Air speed could be extrapolated from previous air speed and inferred from ground speed, engine thrust, and known weather. IRU and GPS could also have provided altitude and thus climb rate. And we know the plane had a bar…

> Air speed could be extrapolated from previous air speed and inferred from ground speed, engine thrust, and known weather. I think this is probably the main sticking point. I don't think you can do this accurately without some direct measurement. If the plane thinks its air speed is fine but it's actually approaching its stall speed because it guessed its airspeed incorrectly, that'd be really bad.

Stall is determined solely by angle-of-attack, which TFA points out. Airspeed doesn't factor in to whether the computer thinks it's about to stall.

Here's the relevant sentence: "Crews involved in similar incidents reported that they assumed the brief stall warnings were generated by the erroneous airspeed readings, a not unreasonable interpretation which breaks down only when one learns that the stall warning calculations are based on angle of attack and do not incorporate any airspeed data."

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