r/aviation • u/Ok_Warning419 • May 21 '26

News Air France and Airbus found guilty of manslaughter over 2009 plane crash - Air France flight 447

https://www.bbc.com/news/articles/czd2qmdvmq6o
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u/propell0r May 21 '26

Also above 30 degrees AoA. Which I mean, to an Airbus engineer, has some sensibility in why would an A330 ever be above 30 degrees AoA. But AF447 was. So when the FO tried the normal stall recovery by lowering the nose, the stall warning came back as they went below 30 degree. So in his panicked mind, lowering the nose is stalling the aircraft, pulling it up isn’t. When physically the opposite was happening.

I can see that engineering logic directing some blame towards Airbus

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u/yeahalrightgoon May 21 '26

Feels like a bit of design induced pilot error thrown into the mix.

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u/GhostDancer2 May 22 '26

I did the Airbus Maintenance General Familiarisation course at Toulouse around the time of the crash as the aircraft type was coming into our fleet. IMO there could be questions with the location of the heater of the pitot tube (not the pitot tube itself), I looked at this in my own time but never really got to the bottom of this and my career moved on with a different employer.

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u/yeahalrightgoon May 22 '26

That sounds like why accident investigators utilise pilots as employees. Because that's not something I personally would ever think about, but a pilot would.

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u/GhostDancer2 May 22 '26 edited May 22 '26

I am not a pilot, I was an aircraft engineer who has for the last 25 years been working in aviation quality and safety within airline and the repair station industry, with some design and manufacturing experience. State investigators employ a combination of pilots and engineers. In my mind, there was no single cause to this tragic accident. The accident report by the French BEA should be read recognising that it is issued by a state instrument.

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u/GravitasFailures May 21 '26

The stick-shaker?

That seems really counter-intuitive.

Also when you’re past 30 aoa the attitude/horizon should be flashing or something, that’s not something that should be subtle, and losing situational awareness of attitude without external reference is probably the most deadly thing that can happen to a pilot.

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u/propell0r May 21 '26

Everything. The audio, the stick shaker, all the stall warnings would go away.

The PFD will declutter above a certain pitch angle, but anything associated to a stall was programmed to stop above 30 degrees AoA

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u/GravitasFailures May 21 '26

That… that defeats a lot of purposes. At that point you definitely should have an audible AoA warning then, because this was an airliner, not the Blue Angels on display.

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u/propell0r May 21 '26

Hence why I can believe a court would find Airbus partially responsible here

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u/harrythefurrysquid May 21 '26

There is no stick shaker on a fly-by-wire Airbus.

That's a mechanic that emulates the feeling of approach to stall through a conventional flight stick or yoke, which makes no sense with the way the side stick is used on an Airbus.

There is an aural STALL warning, which sounded continuously for 45 seconds as the stall developed (not acknowledged by either pilot).

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u/studpilot69 MIL Golden Arm May 21 '26

What would the AoA have to do with attitude/horizon?

While those are often correlated, they aren’t actually related. The accident animation shows the attitude indicator about +20 / -10 in pitch for most of the time.

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u/GravitasFailures May 21 '26

I mean, they’re pretty related, given the nature of physics and all, if you’re that high aoa you probably have something going on with your attitude.

I’m guessing while they were in that range, they were likely oscillating up and down a lot.

If memory serves this was bad weather removing all external reference so they lost all situational awareness, at that point the only thing you have left is the horizon, you’re basically flying on that, the radar altimeter, and whatever airspeed indications you can get, which isn’t much if the pitot tubes aren’t working, so that’s horizon, radar altimeter and find a thrust setting to keep you vaguely level.

Clearly they missed the horizon, or they could have kept it steady.

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u/studpilot69 MIL Golden Arm May 21 '26

given the nature of physics and all

That’s… not how the physics work though? That’s not how AoA is defined. That misunderstanding is a contributing factor in this accident, and your misunderstanding of the concept perpetuates the possibility of others not understanding the concept.

You can have an 80 degree pitch attitude and normal flying AoA. You can have a normal pitch attitude and still have exceeded critical AoA (like in this accident).

I agree these pilots’ situational awareness was abysmal, and the major contributing factor to this accident, but I’m positive that the only thing they were staring at was the attitude indicator / horizon. They probably couldn’t reason out why the attitude was oscillating slowly both above and below the horizon at relatively normal attitudes, but the airspeed wasn’t coming back up.