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Old 29th May 2011, 16:26
  #877 (permalink)  
Garrison
 
Join Date: Nov 2001
Location: Los Angeles
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> Could the crew break the stall, even if they had recognized it? With an
AOA of more than 40° that wouldn't have been to easy: With practically
no clean airflow over the elevators (close to a flat spin), those may not
have responded to a ND input, even if it had be given.


I have talked with several aerodynamicists who were generally in agreement (just theoretically -- no first-hand knowledge) that the A330 probably does not have an unrecoverable deep stall mode and that the airplane would have responded to a nose-down pitch command. In fact there was a brief moment during which an AND command was given, the airplane began to pitch down, and then lo and behold the stall warning came to life and discouraged the pilot from continuing the experiment. It would have been necessary, if I understand the control laws correctly, to manually trim out of the full ANU stabilizer setting of -13 deg. An important point is that the flight path was 25-30 degrees down, and so a stall recovery by reference to the PFD would have required putting the nose 20 degrees or more below the horizon.
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