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Old 15th Apr 2019, 08:43
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The Mad Russian
 
Join Date: Mar 2001
Location: Left seat of a Boeing... mostly!
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[QUOTE=MurphyWasRight;10447583]Interesting experiment would be run the scenario and see if AND does work, which my understanding is that it should not due to column cutout switches. If it does the SIM has this backwards somewhere. Also to notice is whether electrical trim re-appears all at once or begins to work slowly at some point.

Useful discussion of stab screwjack loading here: https://www.satcom.guru/2019/04/stab...and-range.html

Would suggest that the effect we observed was correct for stab in (gross mis trimmed) AND position (stab leading edge UP) and aft elevator applied. We didn't try AND electric trim, just ANU electric to avoid impending terrain impact with our particular scenario.

During the described scenario, the reactivation or 'release' of the stab trim wheels was 'progressive' as the aft elevator back pressure/position from aft stop was released, certainly not a 'switch' like effect.

An aside, both the devices mentioned also have a faults for 'stab trim brake failure', this runs the stab according to aerodynamic loading on the stabiliser. A slow and insidious failure... requires NNC memory item for 'if runaway continues' ... stab trim wheel 'grasp and hold', very easily stopped with the palm of the hand on the opposite trim wheel for this simulated fault. I note this in passing, as not all FFS that I've used have such an expansive fault list.

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