Originally Posted by
bratschewurst
What's not clear from the report is why the PF made any stick inputs at all. My understanding is that, even in alternate law, the computers maintain the pitch and roll attitudes previously commanded until the stick is moved, so presumably the aircraft would have continued straight and level, assuming that was the case when the a/p disengaged.
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But it does appear, if my understanding of the Airbus FBW system (gleaned mostly from these threads) is correct, that the aircraft would have continued in straight and level (and unstalled) flight absent the left nose-up input by the PF.
I think roll drops to direct in alternate law, but it is still a good question - if the aircraft was level it should stay that way. BEA don't indicate the cause of the first left roll - maybe turbulence, maybe the wing stalled, or maybe some input from FBW. They made a left turn shortly before - were they still in the turn when normal law dropped out, and what would that do ?