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Old 23rd Nov 2013, 19:56
  #911 (permalink)  
Bpalmer
 
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>The experts are surprised that the auto trim doesn't stop trimming the plane up once alpha prot is reached, as it is the case in ALT1.<
That functionality only exists in Normal law.
In Alternate law, (if airspeed is available) the protections will provide Low Speed Stability, which is essentially direct law pitch (pitch trim stops, the airplane's natural tendencey to pitch down if faster than the trimmed speed).
If there is no valid airspeed, then that can't work, and you're left with g-load demand with no bottom end.
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