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by StavrosK 4212 days ago
The Air France 447 crash was also caused by pilots thinking the autopilot was on when it was off.
1 comments

Honestly, that's not entirely true, and not very respectful to the pilots in that crash.

AF447 was caused (partially) by the pilot's misunderstanding that holding the control stick all the way back was gonna make the aircraft go up at the best rate of climb, and not put the control surfaces all the way back.

The AP (autopilot) was off for quite some time when the crash happened. What was supposed to be on though, as always, is the Airbus Fly-by-wire system in normal law, that is in between the pilot's controls and the actual commands sent to the control surfaces (ailerons, elevators...). This system was off (in it's direct control law, more precisely) due to the pitot tubes sending non accurate data, because of the icing problem. The pilot didn't notice that.

Yes, sorry, that's what I meant. They had turned the system to direct control law and one of the pilots was pulling back, and they were ignoring the "stall" warning blaring in the background.

Honestly, first of all, who averages two sticks? Like, when is averaging the input of the two sticks ever a reasonable thing to do? This is a major design flaw, in my opinion.

Second of all, why was the "stall" warning even on when the system was in normal law, and thus impossible to stall? All that did was desensitize the pilots, who learned to just ignore the warnings.