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Old 4th Apr 2019, 19:51
  #3159 (permalink)  
GordonR_Cape
 
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Originally Posted by infrequentflyer789
This MCAS signal got through, which some will take as proving the switch position was changed, there is so much else going wrong not sure I would agree (that it is proven). Also, this still doesn't look right per the descriptions we've had:
- MCAS is supposed to have less authority at higher speed (maybe that's it, it is shorter input?)
- If AOA reduces then MCAS is apparently supposed to put the trim back up, if no pilot trim input - yet there isn't and it doesn't
AFAIK MCAS uses the same rate of nose down trim of 0.27 units per second, it is the duration that varies, with a maximum of 9 seconds.
MCAS will 'unwind' the trim only when the AOA reduces below the 10 degree threshold, not when AOA reduces relative to its previous value.
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