B.L.E.

I have heard or read that some high pitch fixed pitch racing props, particularly the ones on full scale pylon racers, will actually load as the airplane accelerates to a certain airspeed. The sound of the engine suddenly dropping rpm at 120 knots or so shortly after takeoff can be quite disconcerting to a pilot the first time he flys one of these planes. With high pitch props, the blades are in a partial stall at low airspeeds, as the airspeed increases, the blade's angle of attack to the airflow decreases and the blade unstalls pulling the engine rpm down as it gets a bite on the air.