PPRuNe Forums - View Single Post - AF 447 Thread no. 4
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Old 27th Jun 2011, 10:09
  #448 (permalink)  
BOAC
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No - you are right, HN, my mistake and I have edited my post - not stall speed, but pretty slow whatever you call it.
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. Alphaprot is less than alphamax and maintaining it stick-free prevents the airplane from stalling.
- please explain the logic here - the a/c was now here near 'stalling' when it all started and was then placed near it by the software??? So why? This defeats me. Suppose for a moment that this happened to 447. Desirable - no. Helpful - no. On a dark night in the ITCZ, confusing - yes. We know that the alpha-prot 'inhibit' would probably have been disabled by the IAS readings.
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