Why does my trim keep snapping to maximum-up whenever I open the main menu?

Question

Just installed Microsoft Flight Simulator (2020), and got a Thrustmaster 16000 HOTAS + rudder pedals.

Hopped into the Mount Everest discovery flight to see what calibration I needed to make to the controls.

The instant the simulation begins, the nose pitched straight up into the vertical, and stall warning started going off. After a bit of wrestling with the stick, I realized the trim was maxed out in the "up" direction. I mashed the trim down button until I was able to get the thing stabilized. Weird but... okay.

I didn't like where my landing gear toggle was bound, so I hit ESC and changed that control binding to be where I wanted it.

The instant I return to the simulation from the Main Menu, the plane pitches up exactly like before - and lo, the trim is maxed out in the "up direction" again. I wrestle it back down again, and so on.

Every. Single. Time. I press the Escape key to bring up the menu, even if I make no changes, the moment the menu closes, the trim snaps to the maximum-up position and has to be wrestled down.

I've tried searching everywhere I can, but aside from a months-old posting on the MSFS 2020 official forums where someone is apparently having the same issue, I can't find discussion of this let alone steps to fix. How do I troubleshoot this?

Running on Windows 10, via Steam, issue began with all settings at default - including the control mapping for the HOTAS.

Answer 1

THIS is the culprit.

For reasons that defy explanation, the DEFAULT control assignment in MSFS2020 for the on-joystick throttle is:

1. Thrust 0 to 100%
2. Trim -100% to 100%

SIMULTANEOUSLY

If you allow MSFS2020 to assign controls for you based on its detection of the Thrustmaster 16000 HOTAS, you should expect to have to go in and resolve many conflicts in the control scheme - but this one is the most obnoxious in terms of it's impact on gameplay.

In my case, the throttle slider was in the full-off position, and so every time I exited the main menu, the simulation takes a survey of control positions, would see that pegged at the bottom of the range, and thus snap the trim to the maximum-up deflection.

You need to clear the assignment of "Control Surface Trimming" from the joystick's various axes unless you have specific intention to use it. I recommend also removing it from the throttle assignment, in case you bump it and override the main throttle control by accident.