PMDG 744 FMC Failure/Fix

[jimjones]

The FMC in the PMDG 744, which had several times successfully guided the plane in a
programmed flight began failing in a number of ways such as thrusting through a set altitude
and departing longitudinal courses and creating havoc along the way.

This plane, once thought airworthy and able to use the FMC reliably, continued to be used
only periodically to maintain knowlege of its use. New planes such as the P-51, Spitfire, B-17
and others interrupted flying the 744.

Recent 744 FMC flights failed. Why? After reloading the 744 with no improvement, recent
changes to FSX were considered. Finally, it was determmined that changes to the joystick
settings to better handle the spitfire were the blame. Reduced null zone values for all three
axes allowed the joystick to introduce spurious inputs to the plane, thus the failure for the
FMC to control. Increasing the null values was the solution. Also helps simple autopilot problems.

When confronted with my error the solution was like the joke: I could not understand why the
ball kept getting bigger and bigger, until it hit me.

Maybe this might help someone in the future.

[Clarke123]

It's quite realistic then, if I recall ther was a real world incident of a 737, I think. The co-pilot had gone to the head and when he came back bumped the yoke with his knee, which, disabled the autopilot because control inputs had priority incase of emergencies. I'm not sure if they crashed or not.

[jimjones]

Clarke, interesting real world incident!