PPRuNe Forums - View Single Post - MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures
Old 13th Jun 2019, 18:33
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DaveReidUK
 
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Originally Posted by safetypee
Also, an EASA certification query implied that electric trim would not be available, and not considering higher non-normal tail angles.
The main issue being that longitudinal trim cannot be achieved throughout the flight envelope using thumb switch trim only”
“Boeing set the thumb switch limits in order to increase the level of safety for out-of-trim dive characteristics”

https://www.easa.europa.eu/sites/def...20ISS%2010.pdf

My understanding of that ESF is that limit switches restrict trim switch movement of the stab towards the extremes of AND (and ANU), not that they remove the ability to trim from the extremes of the range back towards the green.

I'm pretty sure this was discussed extensively in one of the earlier threads.
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