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Old 27th May 2011, 22:51
  #610 (permalink)  
JJFFC
 
Join Date: May 2011
Location: PARIS
Age: 62
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stall warning stops when you are in a stall

Contrary to what is mainly reported, it seems that the pilot recognized a stall but changed his mind because the stall warning stops when in a stall :

"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. "

=> One can understand : the PF is the cause of the stall.

"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 "

=> The pilot recognized a stall.

"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 PF is responsible for a new stall

"the Captain re-entered the cockpit. During the following seconds, all of the recorded speeds became invalid and the stall warning stopped. "

=> when the captain re-entered, no information was available to him

"the PF made pitch-down inputs. In the following moments, the angle of attack decreased, the speeds became valid again and the stall warning sounded again."

=> the stall warning sounded when he pitch-down then his reaction is to come back to the last situation when the stall warning didn't sounded i.e. with the nose up.

It is just a human reaction and the captain had no clue to help him.

QUESTION : since the stall warning stops when you are in a stall ( speed < 60 kt) but sounds when you are recovering, what has to be changed ?
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