Primary finding
Probable cause
The flight instructor’s improper recovery from a practice autorotation which resulted in a hard landing.
Investigator assessment
Analysis narrative
While conducting an instructional flight, the flight instructor reported that he and the student pilot were practicing straight-in autorotation approaches in the helicopter with a power recovery. The helicopter was configured with a throttle control switch rather than a twistable throttle control. During the fifth autorotation approach, the flight instructor forgot to move the throttle control from “Idle” to “Fly” prior to flaring the helicopter. The helicopter descended and landed hard on the runway. During the hard landing, the helicopter sustained substantial damage to the tailboom. The flight instructor reported that there were no mechanical malfunctions or failures that contributed to the accident.