Incident Overview
A flight instructor with 3,000 hours of flight experience and a private helicopter pilot were conducting proficiency flight training in a helicopter. The training involved autorotation maneuvers to practice emergency procedures.
Sequence of Events
During the second autorotation of the session, the helicopter was at an altitude of approximately 300 feet above ground level (AGL). The pilot flared the helicopter, which arrested the rate of descent. Shortly thereafter, the low rotor RPM warning horn sounded. In response, the certified flight instructor (CFI) decided to continue the landing and take the helicopter to the ground.
Outcome
The helicopter touched down hard. The impact caused the main rotor blade to strike and sever the tail boom, resulting in substantial damage to the aircraft.