Copter oscillating in Loiter mode

ArduCopter Copter 4.5
1

I have a quad with the following specs:

Pixhawk cube orange with Here4 gps
T motor MN 5008 340Kv motors
T motor Alpha 6S 40A ESC
6S 22000mah li ion solid state battery
1855 Generic CF props
7.5kg MTOW

The quad flies very stable in Stabilize and AltHold modes but starts oscillating the moment i put it in Loiter mode. The oscillation is better in Poshold but it is still very much there. I Tried to Autotune the copter but it showed the error Autotune: Failing to level. So i’m guessing i need to get the oscillations sorted out before trying to autotune the copter.

I’m running the latest Copter 4.5.2 version and have also updated Here4 to the latest firmware.

Attaching the logs and the flight test videos here..

2

Use ArduPilot Methodic Configurator | MethodicConfigurator to tune it, you clearly missed a lot of required steps.
The existing ArduPilot wiki documentation is very good but it is easy to miss a step, the software in the other hand guides you in a way that is not possible to miss any step.

Without configuration and tuning it is not possible to fly safely and reliably.