TAKEOFF mode is lowering throttle from 100% to ~72% during throw

ArduPlane Plane 4.5
1

During plane launch with AUTO mode starting with TAKEOFF wp, for some reason autopilot is lowering throttle from 100% to ~72% in ~0.3s time, and then gradually raising it back to 100% in ~1.0s of time.
For this plane this time period is crucial for good quatily takeoff, but i wonder why it happens.
Any ideas why its happening?

For that curious people, why ESC signal is starting from 1200us, that is done through lua script, to spin the motors to some idle, and prevent foldable propeller to fold. The only thing it’s doing is raising SERVOx_MIN & SERVOx_TRIM to certain number.

I’m not loading actual flight log, because it is 350+MB of space :slight_smile:

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2

Confirming that mode was definitely takeoff, not just waypoint

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3

It is likely an effect of going from scripting override to throttle control.

I would recommend using pre takeoff spinup in takeoff controller instead of scripting.

4

That script does not override throttle control. The only thing that does is just raising minimum PWM to ESC. Throttle is still controlled by autopilot.