Originally Posted by CONF iture
It must be a big question mark for Airbus why a single faulty ADR allowed the AOA protection to take control of the aircraft. Aircraft was under manual control but the “protection” prevailed … !?
Please refer to the QRH 2.43 for what you should do for speed discrepancies between ADR 1,2,3 , fluctuating or unexpected speed, abnormal correlation of basic flight parameters, abnormal AP/FD/ATHR behaviour, STALL warnings or OVERSPEED warnings etc......
AP/FD ___________________OFF
A/THR____________________OFF
……
Faulty ADR(s) __________ OFF
Remaining Air Data______ CONFIRM
Until we have the final report I am unable to confirm if the crew did/did not follow the UNRELIABLE SPEED INDIC/ADR CHECK PROC and turn off the erroneous ADR output. They received spikes in airspeed giving STALL/OVERSPEED warnings and all the other symptoms of a faulty ADR, and you WILL get a nose down/up bias until that ADR is turned off.
I am still not convinced the GNADIRU was faulty, problems with the output of the GNADIRU unit in the past have been traced back to things like the racking of the box (e.g. hitting the shelf above causing excessive vertical g), or a probe/sensor/air data module failure.
Please do not jump to conclusions.