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I had already asked you this earlier, but now that we have a much more detailed record of 447s final minutes maybe you're ready to answer - at which point didn't "the software" give them what they asked for?
Although this question wasn't addressed to me I'm going to answer it.
The question you ask is disingenuous. The complaint is not that the software didn't do what it was supposed to do but that what the software was doing was not communicated to the crew in an intelligible way.
It's simple.
(a) When the airplane is within the flight envelope the stall warning provides an aural communication to the pilots: SILENCE.
(b) when the software decides the airplane is outside established parameters it provide an aural communication to the pilots: STALL STALL STALL
(c) when the software decides that the airplane has so drastically exceeded established parameters that the data should be considered invalid it provides an aural communication to the pilots: SILENCE.
Now, if you think that the pilots were confused and failed to recognize the stall for what it was then you have to ask yourself how the above represents good software design. Because it does not. It's horrible software design. It's horrible software design for the software to communicate the exact same aural message (and silence is an aural message) to the pilots both when things are 100% good and when things have gone totally to hell.
The question here is not " at which point didn't "the software" give them what they asked for" (Airbus - and BEA - were very quick to answer that).
The problem here is that, FBW Airbuses are flown
differently from conventional airliners. They purely don't give you any feed-back on the side-sticks (and on ATS). And when confronted with a situation of multiple failures, pilots tend to fly by their pants...that is why the PF Co-Pilot voiced his impression about going with a crazy speed.
They were in a turbulent area (no sense of posture), they had no correct speed informations (no
complete visual clues) and
no feed-back on the side-sticks.
jcjeant shows it all...
The stick of PF busy making mayonnaise ..
Remember when you went to your first flying lessons? What were the first clues our instructors told us about identifying an approach to stall? The reduction on the forces needed to move the stick, the lack of reaction and amplitude required from the controls, the buffeting, etc...
The lack of feed-back (and interconnection between) the side-sticks was IMO a major factor, on the inability of the pilots to properly identify the stalling conditions.
One can always argue about the
stall stall synthetic voice warning, but we must remember also, the number of gear-up landings that have been made in the past with the horn ON, all the way down to the tarmac...
Now put that voice coming on when you put the nose down and turn that madness situation into an accident...
Yes, the systems behaved exactly as designed.
Yes the situation was poorly handled by the whole crew.
But when we take away from the man/machine interface such an important clue (feed-back) we are forgetting that those aircrafts are ultimately flown by men and that men revert to basics when in face of an outstanding dangerous situation.