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Old 25th Nov 2011, 11:08
  #502 (permalink)  
Neptunus Rex
 
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Dear Dozy,

I agree with you about the speedbrakes, in that they should play no part in any stall recovery, other than to ensure that they are retracted.

However, I disagree about the stall being irrecoverable. In modern airliners, an irrecoverable stall (the oft misquoted 'Deep Stall') is purely a feature of 'T tailed' aircraft, hence the certification requirement for a Stick Pusher on such types.

A conventional, low tailplane type such as the A330 should never enter an irrecoverable stall. In the case of AF 447, the self-inflicted stall should have been recoverable by pushing the sidestick forward, then helping the desired pitch change with judicious use of nose-down trim. Depending on the altitude, recovery should be accomplished with no more than 3,000 feet of height loss. (IAS/TAS relationship + momentum.)

For the thinking Airbus pilot, on seeing the amber crosses on the Flight Director, which indicate reversion to Alternate Law, the first thought should be:
"Loss of protections - especially Stall Protection."

The next action (CRM) should be to pass that warning to the PNF, with the rider "Watch my back!" Simply, basic Airmanship.
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