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Old 10th Nov 2011, 15:37
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Lyman
 
Join Date: Aug 2011
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There is (to me) a lack of technical discussion of the TRIM operation prior to its travel to NU stop at (near) the top of climb. The accepted wisdom is at 3 degrees NU (-3), the THS stopped moving. The rest of the climb was not followed (augmented, commanded) by TRIM.

It is said that it stopped because the elevators had requisite authority to change PITCH w/o the slab. This infers a data point at which the THS inhibits, leaving to the stick, commands that do not "require" THS follow.

This implies (to me), a computer generated point at which "maneuvering" is left to elevators alone. This is inconsistent (at least to me) with AB philosophy, even in ALTLAW2.

Had the TRIM continued, would we see less mayonnaise, and more stability in the climb to 38k? Was PF "hunting"? I think he was, and though that may be improper, I certainly see how that could happen. Afterall, we know he lost SA with PITCH/POWER from the git, with his intitial input.

The THS was articulating to, (and through) handoff to manual flight, why did it stop? It moved as the PF was ordering a climb, what was different about his initial input from the regime that prompted the FC to stop the THS in the zoom? Again, his initial input caused STALLWARN, so it wasn't for lack of emphasis, or authority, that the airframe sensed the lack of a need for continued THS?

What separates PITCH command (NOT LAW), in auto from PITCH command in ALTLAW2? In the time it takes (took), to climb 3k feet, the PF became accustomed to elevators/results? I realize there is room here for slandering the crew, but it seems to me, the computer was little help in the transition.

I'm looking for an honest answer to an honest question, not flames or politics.
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