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Old 27th May 2011, 17:28
  #114 (permalink)  
Join Date: May 2010
Location: Boston
Age: 68
Posts: 408
Extraction of actions from narrative

An attempt at extracting a logical flow from the narrative. Ellipses (...)
indicate portions I removed for clarity, items such as inline explanations,times and displayed speeds. <comment> are my thoughts.
Bold indicate possible action/reaction chains.

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.
The airplane's pitch attitude <corrected from AOA> 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 airplane was then at an altitude of about 37,500 ft and the recorded angle of attack was around 4 degrees.
<almost regained control?>
the stall warning was triggered again. < by the AOA greater 6 degrees?, mentioned later>

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. < as result of sustanined nose up input?>
The PF continued to make nose-up inputs. The airplane's altitude reached its maximum of about 38,000 ft, its pitch attitude and
angle of attack being 16 degrees.
During the following seconds, all of the recorded speeds became invalid and the stall warning stopped.

<possible "well that worked" reaction by PF who was ignoring displayed speeds at this point anyway? >
The altitude was then about 35,000 ft, the angle of attack exceeded 40 degrees and the vertical speed was about -10,000 ft/min.
The airplane was subject to roll oscillations that sometimes reached 40 degrees.
<falling like a leaf but only sensing side to side not down since steady state,not trusting displayed vertical rate?>

The PF made an input on the sidestick to the left and nose-up stops, which lasted about 30 seconds.
(both said) "we have no valid indications". At that moment, the thrust levers were in the IDLE detent
Around fifteen seconds later, the PF made pitch-down inputs. Inthe following moments, the angle of attack decreased, the speeds became valid again and the stall warning sounded again.

< return of stall warning was confusing since it coincided with actual improvement? Perhap led to nose up command? >
About fifteen seconds later, simultaneous inputs by both pilots on the sidesticks were recorded
<would be usefull to know the inputs and if they matched>
and the PF said "go ahead you have the controls".
The angle of attack, when it was valid, always remained above 35 degrees.

Last edited by MurphyWasRight; 27th May 2011 at 17:46. Reason: Chagnge AOA to pitch attitude Wozo points to /BEA correction
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