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Old 5th Apr 2019, 11:21
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Rananim
 
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That said do disagree with statements on manual trim, pretty strong evidence that at the speed and trim they were in it would be physically very hard or impossible to trim manually without unloading maneuvers that the did not have the altitude for and/or knowledge/training of.
MurphywasRight
If the column forces were too high, one option (if you hadn't worked out how to engage the manual trim, which these guys hadn't) is to turn the trim back on, correct it with the normal electric trim switches, and then turn it off again before MCAS kicks back in. You asked what I would do, that's what I would do.
PaperHanger

They decide to cut out the trim switches at 0540:35, 35 seconds after first MCAS activation.N1 remains at 94% throughout leading to loss of speed control. But If ANU manual trim had been ordered immediately following cutout of stab trim switches, or better still, PF had trimmed back to 5 units(which has a visual marking on the trim index) and then disabled the trim switches,can we calculate if the aerodynamic loads were already too much for manual trim to work.What was the speed at 0540:35?
Captain asks if trim is functional at 0541:46,so that's 71 seconds after trim cutout where no attempt is made to relieve control forces and speed is allowed to build.

Last edited by Rananim; 5th Apr 2019 at 11:32.
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