@bnsgeyer ok, so there’s a problem with the math in the alt_hold angle limiter for heli. @tridge had noted this in the blog on the test QuadHeli as well:
It’s not a problem in the motors backend, it’s a problem in the attitude controller. The math for heli was copied and pasted from multi and the “throttle” in heli is essentially different than it is for multi’s because a good portion of the “throttle” is used for negative collective pitch. So the result is that angle limiter is effective at hover collective pitch.
I fixed it and I’ll test it tomorrow in a real heli. @joolayoyo do you happen to have the tlog for that flight that you posted the bin log for? I’d like to take a look at that if you have it from your ground station.