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Fly-By-Wire Contributed To Air France 447 Disaster
Hugh Pickens writes "The Telegraph reports that although fly-by-wire technology has huge advantages, Airbus's 'brilliant' aircraft design may have contributed to one of the world's worst aviation disasters and the deaths of all 228 passengers onboard Air France Flight 447 from Rio de Janeiro to Paris. While there is no doubt that at least one of AF447's pilots made a fatal and sustained mistake, the errors committed by the pilot doing the flying were not corrected by his more experienced colleagues because they did not know he was behaving in a manner bound to induce a stall. The reason for that fatal lack of awareness lies partly in the design of the control stick – the 'side stick' – used in all Airbus cockpits. 'Most Airbus pilots I know love it because of the reliable automation that allows you to manage situations and not be so fatigued by the mechanics of flying,' says Stephen King of the British Airline Pilots' Association. But the fact that the second pilot's stick stays in neutral whatever there is input to the other is not a good thing. 'It's not immediately apparent to one pilot what the other may be doing with the control stick, unless he makes a big effort to look across to the other side of the flight deck, which is not easy. In any case, the side stick is held back for only a few seconds, so you have to see the action being taken.'"
Yes and no –the reason they were ignoring the voice saying STALL, STALL, STALL was because they believed that the computer software made it impossible to stall the aircraft, and that all the warning meant was "if you turn off all the computer assistance now, it'll stall", not "the computer assistance is already all off, I am stalling".
A second warning that doesn't ever sound in safe scenarios (e.g. FALLING, FALLING, FALLING) might just have made them twig to "crap, it really is stalling".