Rapidly climbing as soon as altitude hold is engaged

Hey Guys,

I got some problems with my quad. I use the 3DR ArduCopter Quad C Frame with the APM 2.6, the 3DR uBlox GPS with Compass, APC propellers 10x4.7 and Motor 850Kv

As soon as I switch to AltHold mode the copter climbs as fast as possible. I read in the common problems, that it is often caused by high vibrations. So I checked it as discribed, but I think it is not critical.

Maybe someone got some good ideas to help me.

kind regards,

Did you try adjusting your THR_MID?


Yes I adjusted the THR_MID allready

Today I reached the fence and the copter switched into RTL. It worked very well. Also the altitude control was no problem. After this I switched into AltHold and it was rocketing against the sky again. That makes no sense to me, in one mode it works and in the otherone it doesn´t.