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Old 7th Apr 2019, 07:48
  #3531 (permalink)  
spornrad
 
Join Date: Jul 2009
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Originally Posted by Derfred


The earlier trim durations you refer to happened with flaps extended. The trim wheel moves faster with flaps extended. That explains the difference.

Nope. Look at the FO trim up input (long one) that stops MCAS. First 3 s of that input moves the stab appr. 1 U up. Even at the lousy resolution of the plot you can see the difference. I copy/pasted all 4 events together:


Or, for more precision: The FO input lasts 10 s and brings the stab up appr. 2.3 U 1.9 U. That is appr. 0.7 0.6 U / 3 s. The third blue arrow from the left does not show that much movement. Flaps up applies to both rightmost events.
And, again, as you raised: Why does PF ask FO to help with the trim (switch)? [Edited because Derfred gave more correct numbers in a later post]

Last edited by spornrad; 7th Apr 2019 at 09:00.
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