Robinson Helicopter Company R44 II N424DP accident near Buffalo, South Dakota

Probable cause

The pilot’s failure to maintain adequate main rotor rpm while maneuvering at a low altitude in gusting wind conditions, which resulted in an emergency landing on uneven terrain.

NTSB analysis

The pilot stated that, while maneuvering during a sightseeing flight at an altitude of between 100 and 150 feet and an airspeed of 50 knots, he reversed course into a strong, gusting tailwind. After making the turn, the low-rotor rpm horn activated. The pilot lowered the collective and executed an emergency landing to uneven terrain, during which the tail boom and landing gear separated from the fuselage of the helicopter. An examination of the airframe and engine, which included a successful functional test of the engine, revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for CEN13LA228 for the full record.