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Old 6th Apr 2019, 16:24
  #3457 (permalink)  
Derfred
 
Join Date: Jun 2006
Location: Brisbane
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Originally Posted by MemberBerry
To stop it yes. But your "blip" still needs to be 50% longer than the "blip" from MCAS, to fully reverse it.

For example if you let MCAS run for 2 seconds, your "blip" needs to be 3 seconds long to not just stop MCAS, but fully reverse what it did.
Correct, or you could do 3x 1-second "blips", each 4 seconds apart. Or 6x half-second "blips". Or instead of counting, just trim repeatedly and/or continually until the elevator force is neutral, like a pilot. Which he never did.

He did say one strange thing though: if it is correct in translation, he asked the F/O "to trim up with him". This was after the second MCAS. He had only responded to the first MCAS with a relatively short "blip" (2.1 to 2.4 units). The response to the second MCAS (presumably with the F/O "helping") was around 11 seconds and took it from 0.4 to 2.3 units (if only they'd kept going another 11 seconds).

So why did he need the F/O's help to activate main electric trim? It's a thumb switch. Was the stick-shaker that annoying he couldn't activate the thumb switch? Could this mystery have anything to do with the two fatally short "blips" near the end of the flight?
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