Primary finding
Probable cause
The pilot’s failure to maintain a proper autorotation profile during deceleration that resulted in the tail rotor assembly impacting the ground.
Investigator assessment
Analysis narrative
During a proficiency flight, the pilot was demonstrating an autorotation, and the nonflying pilot was following on the flight controls. While holding the flare to land, an excessive amount of aft cyclic was abruptly applied, and the tailskid and tail rotor contacted the ground. The pilot leveled the helicopter and completed the autorotation. The helicopter spun about 90° to the right before it came to a stop. The tail rotor assembly, tail boom, horizontal and vertical stabilizers, and tail rotor drive shaft couplings sustained substantial damage. The operator reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.