With 2.9.1b engaging Loiter the quad stays for 1-3 seconds and you can hear the motors are controlled, then suddenly it shoots up. Ive read about the throttle mid setting but if thats the case here wouldnt it shoot up straight away?
If someone could help me analyze the log that would be nice.
The next release of code will use x and y Accel for a much better position hold. It's good practice to check all three Accel values and make sure vibration is minimal.
Good luck and fly safe.
I have been told by people here that is caused by 'too much vibrations' on the APM, and that the APM needs to be isolated. I haven't dug through the 2.9.1x code yet to determine why excessive, presumably cyclical (no directional bias), noise in the Z axis acceleration would result in the craft thinking it needed to climb. But I'm told it does right now.
Current diagnostic ideas include during on 'raw' mode and dump the logs after landing and specifically look at the z acceleration when you have the craft reliably hovering in stablize mode (not alt-hold, but when you're moderating the throttle yourself to maintain hover).