Originally Posted by
predictorM9
I don't think that the airbus design philosophy of a sidestick without feedback has caused the accident. Also, how do you generate the feedback when the speed data is lost? You can synthetize something based on the AOA vane sensor, but the fact that there was icing in this case precisely meant that all data was suspect. IMHO generating a feedback based on faulty sensors is even worse than no feedback at all.
You are right about control feedback being wrong in UAS (it can only be thus), but Conf wasn't talking about that sort of feedback but rather visual feedback of what the other guy is doing with the controls.
Whilst I agree that is a potential disadvantage of side stick, I actually don't think it is relevant here - PNF seemed to know perfectly well when PF was climbing or overcontrolling roll (in fact he seemed more aware than PF himself).
See also Bearfoils post(s) on the other thread:
http://www.pprune.org/6619313-post1529.html
But that doesn't remove the fact that the stall alarm design is completely unnatural and misleading, which is a big design flaw.
It is, but I believe there are reasons behind that design and it would be foolish to just call for changes to it without understanding
all the logic fully. Clearly the designers never thought a bus would be <60kts in the air, or maybe they thought if it was, it was already lost (may be right), or that the crew must have had enough warning of stall already by that point.
In this case, by the time the SW goes on vacation, the AOA is up at 30deg or more, airdata is going haywire due to high AOA, and the crew have seconds to recognise stall (where they didn't in previous minute of continuous warning) and push nose down over 30degrees (from full NU trim) to get anywhere close to a recovery. With no outside visual reference. And we're so far outside flight envelope we have no real idea how the airframe would have responded to controls. Was it
really, practically (not theoretically) still recoverable at that point ?