In the krup video it looks like gyroscopic precession takes over once the wings stop providing lift and the aircraft is being controlled by the torque of the prop oriented from it's CG until lift is regained. The flaps on the K4 almost make it hover like a hover craft just before initiating that manuver and during the recovery exit from it. Don't we call that a ground loop when it happens during landing or takoff, except the runway gets in the way of the flip when the tail begins to swap places with the nose?
Didn't a P51 pilot in WW2 claim a kill based on this manuver?
