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Old 27th Jun 2011, 09:11
  #447 (permalink)  
sensor_validation
 
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Originally Posted by BOAC
below stall speed
Originally Posted by HazelNuts39
Are you sure?
In cruise, VLS is a speed that provides a certain margin (0,3 g?) to buffet onset. The zoom climb occurred because the FCS entered into alpha-prot law and then maintains AoA=alphaprot until the pilot moves the sidestick. Maintaining alphaprot stick-free prevents the airplane from stalling...
As we all now know from earlier posts, no such thing as "stall speed" its all about AoA. The A340 clearly went into a 'ballistic trajectory" too slow to maintain level flight at that altitude even with full thrust, around 20 seconds of "less than 1g" as it went over the top with a sharp drop in pitch angle? Its not too clear to me whether it was the pilot or protections that successfully managed the flightpath to recover speed. No mention of stall warnings, and as previously commented AoA not shown, nor how how deep the nose down pitch during recovery. See also Sully's landing on the Hudson - pilot or protections managing pitch/AoA?

Last edited by sensor_validation; 27th Jun 2011 at 13:14. Reason: Fix quote: apologies to HN39
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