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Old 8th Jun 2011, 16:36
  #1623 (permalink)  
GarageYears
 
Join Date: Jun 2009
Location: VA, USA
Age: 58
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bearfoil:

But she was trimming for climb, automatically, so much so that the a/c stalled, having lost autothrust and assumedly, "Stall" (aPROT). So this is the deadly combination. A/P drops, a/c climbs, and Stalls. Thirty seconds over Oraro.
I suppose it's a matter of opinion, but you do have a tendency to be a little inciteful...

"She was trimming for climb, automatically..." --- really? I can't find anything that states that is true.

From 2 h 10 min 05 , the autopilot then auto-thrust disengaged and the PF said "I have the controls". The airplane began to roll to the right and the PF made a left nose-up input. The stall warning sounded twice in a row.
<snip>
At 2 h 10 min 16, the PNF said "so, we’ve lost the speeds" then "alternate law […]".
<snip>
The airplane’s angle of attack increased progressively beyond 10 degrees and the plane started to climb. The PF made nose-down control inputs and alternately left and right roll inputs. The vertical speed, which had reached 7,000 ft/min, dropped to 700 ft/min and the roll varied between 12 degrees right and 10 degrees left. The speed displayed on the left side increased sharply to 215 kt (Mach 0.68). The airplane was then at an altitude of about 37,500 ft and the recorded angle of attack was around 4 degrees.
From 2 h 10 min 50, the PNF tried several times to call the Captain back.
At 2 h 10 min 51 , the stall warning was triggered again. The thrust levers were positioned in the TO/GA detent and the PF maintained nose-up inputs. The recorded angle of attack, of around 6 degrees at the triggering of the stall warning, continued to increase. The trimmable horizontal stabilizer (THS) passed from 3 to 13 degrees nose-up in about 1 minute and remained in the latter position until the end of the flight.
Any THS trim effect (due to PF input) did not ramp in until nearly 1 minute (46 seconds) into the reported sequence of events. There is nothing that indicates anything other than demanded trim (PF nose-up inputs).

Care to explain it differently?
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