Primary finding
Probable cause
The pilot’s failure to apply full power during the practice autorotation recovery, which resulted in a hard landing.
Investigator assessment
Analysis narrative
The flight instructor reported that he and pilot receiving instruction were conducting an instructional flight to include practice autorotation maneuvers. The flight instructor reported that he was demonstrating a straight-in autorotation with power recovery but did not apply full power as required. About 10 ft above the runway the low rotor horn sounded, and the pilot attempted to go around, but the helicopter bounced on the runway and pitched forward. The main rotor blades contacted and severed the tail boom, which resulted in substantial damage. The pilot reported there were no preimpact mechanical malfunctions or failures with the helicopter that would have precluded normal operation.