Originally Posted by
Lyman
infrequentflyer789
Thanks for a meticulous and thoughtful reply. I quote the initial BEA text when they sought to describe PF's actions at a/p drop. One can fall back on the dual language, made an issue here, but I prefer to place more confidence in the text as translated, to avoid weasel wriggling.
Me, I'll go for numbers every time (blame it on engineering or software background, take your pick). Text has been written by a frenchman, edited by a lawyer and translated by a linguist - the numbers have far less room to wriggle.
As to overspeed, it
could have been - but I don't think it was. Overspeed is shown in the trace on P111, and doesn't trigger in the time region shown, which includes the A/P drop.
Also, PF pitch actions were NU first (see same page, below the line is stick-back, above is forward) - whatever the text might say
I notice your discomfort with a connection twixt UAS and the STALL. I share it. I also am not at all convinced the Pitots misbehaved in any way.
I think they
probably did, but my concern is more that beyond causing A/P drop and Alt Law, pitot failure may have no bearing on what happened. Which means that any
other failure leading to alt law could lead to the same result - and fixing the pitots is a convenient scapegoat that leaves larger problems unaddressed.
So it is possible yet to retain an open mind. Demonstrably it is also predictable to judge the pilots incompetent in the court of easy chair PPRuNe jurisprudence.
I judge them not (or try not to) - and am not qualified to do so anyway. I try to
understand their actions from a user-interface / controls / human-factors perspective, and I await the human factors report with interest.
If I have come to any judgement so far, it is that there were major systemic operational failures that put this crew up there (along with other AF crews if the sim test rumours are true)
unprepared to cope with this scenario. And it was a
known scenario,
precisely known, but clearly not assessed - until after the crash. To quote AF (from
Press Releases ):
Starting in May 2008 Air France experienced incidents involving a loss of airspeed data in flight, in cruise phase on A340s and A330s.
But did they train, or even assess, their A330/40 crews to handle a loss of airspeed in cruise ? It would appear not (according to the BEA).