Originally Posted by
silverstrata
Yes, manual trimming with the trim wheel only shows up as trim position, not as trim input. So at the end of the previous flight, they were spinning the big wheel around by hand.
That seems to be the case, which then leads me to this question: why didn't this crew do likewise? (Day, VMC). As someone noted above, the CVR may give some insight on why.
Did they see (perceive) different symptoms than the previous sector's crew?
Did they diagnose the problem the same way?
Was this malfunction subtly different?
@CONSO: how can they afford not to?
From a CRM perspective, I'll make a case to you: one of them (whomever at that point is non flying, so left seat?) cranking on the manual trim wheel with great vigor would reduce the load to where one pilot can handle it. That trim wheel will move the control surface to relive "yoke forces" ... but as I've not flown that aircraft, I'll accept that this case may have holes in it. (Lack of CVR information also makes me wonder what else was going on in their crew coordination effort) And that's all good to consider ... unless ... the one who cranks the trim wheel (for an unknown reason) accidentally rotates it in the wrong direction. That would make things worse.
I make no assertion that this happened.
I only mention that outside chance because, under stress, sometimes people do stuff that you (and they) would not expect. (And from running aircrews through sim training some years ago, as you task load a crew more and more you get some oddball results some times ....)
That thought leads me back to .... pilot training.
Company issue: lion air.
Training materials issue: OEM, among others, differences courses, etc.