Quote:
emu787:
did the AFCS detect low speed - about to get a stall or low speed buffet boundary approaching (erroneous airspeed information) and the computer pitched the aircraft nose down and applied full power thinking this is the way to recover. This would almost certainly result in instantaneous excessive speed that would test the integrity of the airframe to its limit.
takata
It seems very improbable considering A/THR and AP OFF => Alternate Law2 (protection lost) due to unreliable Air Data (ADR disagree). Moreover, Air France ADIRUs (Honeywell) are different from Quanta's (Northrop-Grumman).
S~
Olivier
to
Takata :
How do you know the aircraft was actually aware of ADR DISAGREE at 0210Z ? The sequence of ACARS messages says NAV ADR DISAGREE (which sounds somehow something else than F/CTL ADR DISAGREE ?) at 0212Z, giving us a full minute at least between A/P OFF A/THR OFF and your proposed going into ALTN LAW 2.
I would rather suggest that the aircraft was, at 0210Z, just after AP disconnect, in ALTN LAW 1, not yet aware of ADR DISAGREE condition.
Which would mean that Low Speed Protection was active. Precisely, while the pilots were thinking "we're hand flying now", the aircraft applied "gentle progressive nose down input" without any kind of warning other than... STALL STALL STALL... Interesting ?
Anyone could disprove this, and do not hesitate to go very technical.