Drone physics staggering after Z-rotation

Hey guys,

I recently switched from Unity to Unreal and my first project is a simple Drone-simulator.
So while the drone flys unrotated(Z=0), everything works fine and when i release the buttons, the drone returns to its starting position on x and y.
But when I rotate the drone around Z, instead of returning to 0-position the drone staggers more and more and at the end flips over. I don`t know what is wrong, would be very nice if someone could help me.

109099-drone_tumbeproblem_setangularrotation.png

I think it has to do something with the rotator.