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A comment on Ethiopian Airlines 737 MAX Investigation Preliminary Report. Parent comment

Re:Ethiopian Airlines 737 MAX Investigation Preliminary Report by cjbprime on Thursday April 04, 2019 @03:31PM (#19576226)
> Its been noted in previous discussions that while it would be difficult, the load can be overcome if both pilots were to operate the manual trim wheel at the same time.

I haven't seen that noted anywhere, and have seen it theorized as impossible without motor assist, given their airspeed and with the elevator opposing. Got a link?

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Re:Ethiopian Airlines 737 MAX Investigation Preliminary Report by swhitt on Thursday April 04, 2019 @06:01PM (#19577541)
Manual Stabilizer Trim

Excessive airloads on the stabilizer may require effort by both pilots to correct the mis-trim. In extreme cases it may be necessary to aerodynamically relieve the airloads to allow manual trimming. Accelerate or decelerate towards the in-trim speed while attempting to trim manually.

https://www.pilot18.com/wp-content/uploads/2017/01/B737NG_FC... page 312 (8.16)

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Re:Ethiopian Airlines 737 MAX Investigation Preliminary Report by cjbprime on Thursday April 04, 2019 @06:08PM (#19577598)
To be clear, that's a link that agrees with me that it can be impossible, not a link that says they just needed to work harder.

It's also from a 20 year-old manual, and isn't present on newer manuals, and pilots haven't trained on it in decades. Not appropriate to expect pilots to know, and possibly not helpful here: the pilots were low altitude, so allowing the nose to drop even further (to relieve aerodynamic load) may have been deadly too.

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Re:Ethiopian Airlines 737 MAX Investigation Preliminary Report by swhitt on Thursday April 04, 2019 @06:37PM (#19577793)
https://www.satcom.guru/2019/04/stabilizer-trim-loads-and-ra... does a pretty good job of summarizing it I think. It sounds incredibly difficult to do.
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