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WalterBrighttoday at 2:11 AM4 repliesview on HN

The AF 449 was in a stall, and the pilots panicked and did exactly the wrong thing. The pilot came out of the lavatory and immediately realized what was wrong, and pushed the stick forward. But it was too late.

If the captain could figure it out, so could the computer.

I recall another crash, not so long ago, of a commuter plane where the wings iced up a bit and the airplane stalled. The crew kept trying to pull the nose up, all the way to the ground. They could have recovered if they pushed the stick forward - failing basic stall recovery training.

There are many others - I've watched every episode of Aviation Disasters. Crew getting spatially disoriented is a common cause of crashes.


Replies

filleduchaostoday at 11:35 AM

No, one of the pilots put the plane into an aerodynamic stall because they had failed sensors giving them erroneous airspeed information and he kept overriding the other pilot who was doing the correct thing to recover from the stall he had put the aircraft in.

What exactly was a computer at the time supposed to figure out with unreliable data, especially after a stall had first developed?

Also in fairness I was a bit too opaque with my point, which is that 1) LVL requires the pilot to actually press it, which they are unlikely to do if like you yourself have mentioned they are clueless about what situation they're actually in, and 2) LVL is not appropriate stall recovery so I don't really see how it is relevant to a case of an aerodynamic stall.

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shmeeedtoday at 2:00 PM

(It was AF 447.) I take this opportunity to recommend Admiral Cloudberg's excellent analysis (longread): https://admiralcloudberg.medium.com/the-long-way-down-the-cr...

sseagulltoday at 4:27 AM

> a commuter plane where the wings iced up a bit and the airplane stalled. The crew kept trying to pull the nose up, all the way to the ground.

There’s probably a lot that match, but sounds like Colgan Air 3407 in 2009 (the last major commercial airline crash in the US before the mid-air collision earlier this year in DC)

https://en.wikipedia.org/wiki/Colgan_Air_Flight_3407

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manarthtoday at 9:41 AM

    > "If the captain could figure it out, so could the computer."
The autopilot had disengaged, most likely because the pitot tubes had iced over.

The aircraft system entered ALT2 mode, where bank-angle protection is lost. Protection for angle-of-attack is also lost when 2 or more input references are lost.

You might describe these circumstances as the computer saying "I don't know what the heck's going on, you humans figure it out please".