Running out of stab trim on the approach?? Real vs sim

[HighBypass 2,339]

This question is directed to pilots of the big iron, at heavy landing weights, specifically the MD-11  carrying about 90 tons of payload.

When the autopilot has captured the localiser and the plane is configured for the approach, does the autopilot run out of available stab trim?

I would suspect that the answer is a definitive NO! I also suspect the autopilot uses elevator input in conjunction with stab trim.

I think one of the issues within the SIM (FSX:SE) is that the autopilot controls pitch using stab trim alone even if the aircraft has elevators too.

(Yes, it seems that I appear to have found another of Sky Sim's MD-11 foibles..)

Thanks.

[FDEdev 955]

Maybe the CG is too far forward due to wrong loading? Another reason would be a too low approach speed. Theses are the only two reasons I can think of why you could run out of stab trim, regardless if the elevator is being used as well or not.

Edited November 11, 2019 by FDEdev

[HighBypass 2,339]

The CG was quite forward at around 20%, but still within limits according to the Sky Sim manual (12-34%).

[HighBypass 2,339]

I've revisited the cfg file with a "fudge" which at least seems to look "correct" when compared to the real thing. htail_incidence is now -1 rather than +2. My initial findings are at the end of my screenshot thread: https://www.avsim.com/forums/topic/563326-lima-to-miami-mad-dog-cargo-time/?tab=comments#comment-4105550

I shall carry out some more flights to see if this setting is good enough dynamics-wise, or if it is TOO good 😉