How does the Qstabilize and FBWA algorithm work without moment of inertia?

How does a VTOL quad plane level itself without the user telling it the moment of inertia?

Tuned PID loops.

The code’s all in there :wink:

Can you point me to something more detailed?

There is a Dev section in the WiKi called, Learning the ArduPilot Codebase. From there, you can check out the Coper Code Overview which has libraries that are shared with Plane and Rover.

Enjoy!

Thanks Greg, the links you provided were very insightful. Have a good one.