Qualityman,
I had read about a 109 (at speed) experiencing retreating blade stall with the appropriate roll and pitch. This came on quite fast and before the pilot could react the aircraft rolled the other direction. Also quite rapidly. The concensus was that the advancing tip had gone transonic with the corresponding huge increase in drag.
I don't even like imagining the forces on the blades and fuselage at that point.
Anyone know the tip speed at vne for the 109?
fly safe