pj2 / HN
I'm slightly mystified by the bulletin's discussion of High Angle of Attack Protection. Shouldn't they discuss the zoom-climb in the context of High Speed Protection:
My reading is partially as yours.
Crudely:
High Speed Protection:
Prevents exceeding VMO or MMO by introducing a pitch up load factor demand.
The pilot can NOT override the pitch up command.
This "protection" is entered at the same point as the AP disconnects. 0.86M is the limit, 1st excursion <<In
the two second period after the initial speed excursion above Mach 0.86 the Mach number decayed to 0.855>> to 0.87M disconnected the AP. The small / brief excursion probably did not generate much of a pitch up, but <<
and then increased again to 0.882. It remained above 0.86 for two seconds before decreasing and remaining below 0.86 for the remainder of the turbulence encounter>> the next probably did more (longer / greater exceedence) and the combined 2 excusions now left the aircraft in a climbing attitude.
Meanwhile <<
Five seconds after the autopilot disengaged, the thrust levers were closed>> and <<
Ten seconds after the autopilot disengaged, the corrected or phase-advanced angle of attack (a computed parameter which is not recorded but can be calculated by Airbus Industrie from the DFDR data) reached the 'alpha prot' value>> i.e. we had a climbing attitude, zero thrust, and reducing (due windshear) M No hence IAS etc., all at Cruise Alt. Hardly surprising it got to Alpha Prot - it would have to eventually.
For 18 seconds after the autopilot disengaged the aircraft remained within 200 feet altitude of FL360 but once AoA law was invoked at 14:21:50 hrs, the aircraft's attitude began to pitch nose-up.
The pitch-up trend continued for 17 seconds reaching a peak of 15° nose-up shortly before the first nose-down sidestick command was applied
I don't wish to judge, but 'AP Disconnect' is a Red Warning, and whatever else is going on, my training is someone (preferably HP) has to say "I have control" and fly the ac (Rule 1 of any emergency...)
NB the duration of this climb is 35s... that is a long time to leave an aircraft with nobody flying - especially in severe turbulence. 18s is still a long time, and the A340 hardly deviated in altitude more than the A330 (AP in throughout).
I only add this in answer to the points above - I have not followed the AF330 theories as to exactly how this incident might relate to that accident.