[HELP} - Need stable loiter

ArduPlane
1

For a project I am working on, we need a very stable loiter. I notice I have an AltErr and the plane is oscillating while in loiter, about 10-15 meters and speed is varying as well. I suspect it is a gain on the GPS, but not sure. What do you all need to be able to help?

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image2138×710 418 KB

Appreciate any insights.

2

posting a full log would be helpful for sure.

3

Here’s the log:
https://drive.google.com/file/d/1wkmbGY-T0vkda4UgWW0FnoqZS8QrfJC5/view?usp=sharing