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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)

#151

Post by afterburner »

whycome wrote: post #42
braza wrote: post #38

Since I started to study airline accidents, so far this one of the most fascinating in terms of human aspects and Crew Resource Management. The fact that the whole situation deteriorated less than 10 minutes after the Captain went to rest, it’s one of the biggest contrafactuals about this case.

> contrafactuals As in “if the captain didn’t go to sleep, they’d have been fine”?

Not OP, but more specifically, if the most experienced flight officer didn't leave the cockpit just as they were flying into the worst part of a storm and left the matter to the reluctant and nervous junior officers.

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

#152

Post by ericbarrett »

local_issues wrote: post #80
turnsout wrote: post #56

Earlier quoted context omitted.

To be fair, it sounds like this crash caused airlines and regulators to demand much more adverse event training, including high-altitude stall recovery. But according to the article, Airbus hasn't addressed the split control issue…

There isn't a "split control issue," the split control setup is fundamental to the way the Airbus control schema works. Changing it would be a non-starter.

It seems like an avionics warning—“conflicting control input” or the like—would go a long way here, and not change anything fundamental. Maybe Airbus implemented that since?

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

#153

Post by boredemployee »

goles wrote: post #113
sambapa wrote: post #101

Earlier quoted context omitted.

If you are involved in a plane crash then statistically you survive. So microscopically small chances of something bad happening times not so small chance of dying in a plane crash = nothing to worry about, you have to be incredible lucky to be so unlucky.

Maybe I’m just fucked up but I think you missed the humor in describing to a guy who is terrified of flying exactly how he would die but that it’s all gonna be okay.

haha. the thing is that when you have this kinda fear you want to avoid feeling that fear at all costs. Even knowing that it is extremely rare to happen, even knowing that its easier to die seated on my chair while I type for whatever reason.

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

#154

Post by afterburner »

jmyeet wrote: post #2

It's kind of amazing how many of these accidents can come down to the pilots forgetting the most basic things. In this case, ultimately, the pilot and the co-pilot were exerting opposite controls. One to pull up, one to push the nose down. In a stall you push the nose down to gain aerodynamic lift. That's like Flying 101. But I guess when you panic, the natural instinct of wanting to pull up kicks in when you're rapi…

> But why keep climbing when something is wrong?

Two possible reasons in this case.

1) Bonin might not have understood he was in full manual control, and that the computer was no longer restricting his pitch up command to the maximum advisable pitch.

2) The stall warning was intermittent on the way down, because it turns off below a certain air speed. Of course, low air speed contributes to stalling. They were stalling the whole time, but ironically as they started to gain air speed (a good thing) the stall warning would kick in because it was no longer below the lower limit for a stall warning.

Also there's the ever present reason of panic, brain-lock, confusion, etc.

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

#155

Post by goles »

boredemployee wrote: post #153
goles wrote: post #113

Earlier quoted context omitted.

Maybe I’m just fucked up but I think you missed the humor in describing to a guy who is terrified of flying exactly how he would die but that it’s all gonna be okay.

haha. the thing is that when you have this kinda fear you want to avoid feeling that fear at all costs. Even knowing that it is extremely rare to happen, even knowing that its easier to die seated on my chair while I type for whatever reason.

I can’t tell you how happy I am you got it.

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

#156

Post by flerchin »

cedws wrote: post #126
Tronno wrote: post #98

In post-mortems involving pilot error, what strikes me is that airliner cockpit design sounds so convoluted, unintuitive, and just plain bad . The burden of disentangling this bad design is always placed on the pilots - through extensive training and rote memorization - which inevitably fails under stress. In this particular example, consider: - the opposing pilot inputs being signaled only by a pair of little green…

I also wonder why airspeed is derived by some formula applied to the measurement of flow along a tube that can be blocked by ice and become useless. Why not use GPS primarily and fall back to that if needed? Or the other way around even. If you expect an instrument to routinely fail, it just seems logical to at least have a backup.

Jetstreams are hundreds of kph. Meaning groundspeed can be hundreds of kph off of airspeed. Meaning GPS is a very poor backup airspeed indicator.

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

#158

Post by [deleted] »

jcalvinowens wrote: post #91

The article misses the key takeaway from this incident IMHO. When the controls were pegged at full aft deflection, the stall warning would cease , because instrument readings in the deep stall were considered invalid by the computer. Whenever the pilot would start to push forward to recover, the computer stopped rejecting the readings, and started sounding the stall warning again! So every time the pilot started to d…

[deleted]

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

#159

Post by afterburner »

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…

Perhaps the physical effort of struggling against his co-pilot would have made him realize he was doing something wrong. It's too easy to pull back full on a fully non-mechanical control, and just lock up there.

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

#160

Post by cccbbbaaa »

ericbarrett wrote: post #152
local_issues wrote: post #80

Earlier quoted context omitted.

There isn't a "split control issue," the split control setup is fundamental to the way the Airbus control schema works. Changing it would be a non-starter.

It seems like an avionics warning—“conflicting control input” or the like—would go a long way here, and not change anything fundamental. Maybe Airbus implemented that since?

There is an audible “dual input”, which was triggered on this flight.
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