Trim Adjustment in planes with AP that use trim

[calypteaviation]

I’m working on profiles for Prepar3D (mostly A2A, but the problem affects default aircraft as well) and I stumbled upon a problem.

There is no (functional) trim adjustment in CLS profile manager (Movement % accepts values >100 and I need 60 or 70).

What happens in the sim. The problem.

When autopilot in C172 is engaged in any pitch mode (VS or ALT) it controls trim and by trimming the aircraft it achieves the selected condition (keeps the altitude or vertical speed). As CLS2Sim reads my P3D trim values – it adjusts trim on the device accordingly. However – if I disable the AP – I get a significant pitch up or pitch down effect as the device is over-trimmed.

This happens in both directions. When on AP and at low speed, the AP sets high nose-up trim. When AP is disabled – I get a strong pitch up command from the device (and I need to re-trim the plane). When flying at high speed – I get the opposite – significant nose-down effect.

The easiest solution for this would be to adjust the device trim to the simulator. Currently, there is a “Movement” option under Trim in Profile Manager. It seems to be scaling the trim effects on the device, but only one way – enlarging them. If I could scale it down (to 80, 70 or 50%) I would get exactly what I have in the simulator.

[calypteaviation]

I solved the problem with Autopilot settings – I set “Percent of way used by AP” to 10 in Cessna 172 by A2A (instead of 100). Currently, simulator trim while on AP matches CLS trimming.

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