Originally Posted by alf5071h
...what we can learn is if the 767 AP is overpowered, the the auto-trim moving the stab to reduce stick force to help the pilot...
So this one's for you
Originally Posted by
testpanel
A simple 757/767 driver here....
I asked myself if this is a sort of CWS function in the 76, a leftover from former Boeing aircraft. Anyway, if you deflect Column to pitch, as A/P would do, the trim will follow with a delay, as A/P would do, well, rather that's what a still active A/P does, right?
I see a 5 second delay in the FDR, when trim starts to follow control input. And yes, when trim followed nose-down then ...
Originally Posted by alf5071h
...the recovery nose up pull is most disadvantaged by the need for more force to pull up
As a side note, I briefly thought of the Ethopian MAX trim as well, like you. I just wouldn't mention it, cause it had not much negative effect:
Ethopian suffered from large Trim down, combined with increasing airspeed. The result was eventual complete loss of pilot elevator authority, impossible to counter trim.
This ATLAS flight had eventually added 1 Trim Unit nose down, also combined with increasing airspeed. Had it not been G/A with trim up before, they'd ended with like +3.8 units. BUT: at the end they were able to pull +4g. So loss of control authority wasn't a factor.