Extreme lift with f450 apm2.6

A few months ago, I made my first quadcopter with following specs:
cheap f450 frame
1000kv aliexpress motors with 30A esc’s
APM2.6 v3.2.1
4s 5500mah lipo
battery monitoring module

After a few turbulent tests I fixed most of the major issues. But the next test started in stabilize and after switching in loiter the quad was stable for about 5 s (like it schould, constantly correcting) but then it abbruptley accended to 30m (from 2m) with the throttle in 50%. Something worth noting was a kind of delay I felt when handling the craft. Then I panicked and switched back to stabilize to land the craft safeley. Afther that I Reinstalled the firmware and did all the callibration again.

I don’t know what caused this. I checked the barometer and the measurments seem reasonable. I Attached the log below. Something worth watching is Alt, BarAlt, GPS; Alt. the x/y movement looked stable
Can anyone help?

19-04-18_18-31-24_1.bin (141 KB)

Please check your vibration level.

It isn’t mounted on a vibration mount, but how can that affect the height of the quad?

Reading this might help…

and search for “vibration” here.

Vibration effects the accelerometers which can cause exactly what you are reporting as Hari says. Enable vibration logging and make another flight. But you for sure need vibration isolation of same kind in any case particularly with that old and out-of-date Flight Controller.

Ok, I will do that. But I also crashed the drone and 1 esc is burned out, so I will need to order new one’s. Really appreciate the help!

4 small squares of Zeal gel work well or one of the many ball mounts.

Ok, I will make a custom vibration mount. I have the original one, but it didn’t fit the quad. I tought it wasn’t that important. Thanks everyone!