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Old 1st May 2019, 12:33
  #4679 (permalink)  
GordonR_Cape
 
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Originally Posted by MurphyWasRight
It may (or may not) be helpful to remember that the autopilot does not require MCAS help.
This reinforces the fact that this is fundamentally a stick feel issue rather than a critical instability that could kick in under extreme but still in certified envelope conditions.
An interesting point! I can only assume that this has something to do with the autopilot not using AOA as an input like MCAS does, but rather gyro pitch (and other parameters).

I previously asked the question: How could the autopilot ever get into a high AOA situation? One answer was if the autothrottle is disabled. The implication being that the autopilot could keep increasing the nose up pitch until the stall warning activates, and the crew intervenes. I hope that scenario has been carefully tested?

This also touches on the question of whether the MAX autopilot was specifically programmed for the region of high AOA characteristics covered by MCAS, and whether it was tested under actual flight conditions?
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