Originally Posted by vovachan
Why was the AOA protection shut off? The computer continued to receive valid AOA info (which is not available to the pilot btw).
Because flight controls computers must constantly crosscheck AoA info against measured airspeed and known weight to see whether they are valid and can be safely applied when alpha protection is needed. Firing AoA protection based solely on alpha info seemingly did not sit well with fellows developing and certifying Airbus flight controls. Firing stall warning is fine - it still leaves the last line of defence, the pilot, to determine whether AoA vane measures realistic AoA and its advice is best heeded or it got damaged and stall warning is to be disregarded.
EDIT: I have to stand corrected on this; system is a bit simpler as FCCs don't crosscheck AoA vs speed, they just check whether both signals are valid, not consistent with each other. Inconsistency won't trigger law degradation, jut CHECK GW mesage on MCDU.
Life in a cockpit can get tough sometimes.