Crash after autotune heavy lifter Octa 10 kg copter 3.5

ArduCopter Copter 3.5
1

After having a pretty good first flight with the default PID parameters, I made a successful autotune in poshold. I did it all at once not locking the pitch and roll first. Mabey this is not the way to go?
I saved the parameters and started a new flight. Systems started to wobble when taking off (pitch and roll, but yaw seems to be stable) and was not performing like before. I assumed I had to cancel the mission at that point but thats history now. I started a autotune again and system was more or less out of control. Switched of autotune and went back to poshold but couldn’t save the copter anymore. Despite a crashy landing, luckily, damage is almost zero!
I have added the log file links. One file is during the successful autotune, the other one is the second autotune and crash. Any advice is welcome!

Log during 1st autotune: https://1drv.ms/u/s!AsyuUF9kIzhqgpYCyu2EEDkcOtCv_A
Log with new autotune parameters and 2nd attempt for autotune and crash: https://1drv.ms/u/s!AsyuUF9kIzhqgpYD4_z3lM2SmzAVvQ

parameters_after_autotune.PNG748×445 19.5 KB

2

please share files in a usable way, not microstop, which is asking for login.
if you have a google account, share using drive.google.com

3

Link to google drive:

https://drive.google.com/drive/folders/1fE9CL2ULSPwTwZMQNbE82MOw2oAr5YOy?usp=sharing

4

I look at the *10-10-38 log:

the corrections are too big, I would reduce P,I and start over, or start over with defaults you found ok.
First, as you consider it to be a “heavy lifter” - I guess you have some bigger props on it, and/or it’s sluggish, reduce the ATC_RAT_RLL_FILT (and pitch) from 20hz to something like 8 or 6

if the weight distribution is the same in pitch/roll, and the frame is symmetrical, you can just tune one axis, then copy it over to the other.