Robinson R22 - BETA N784SH accident near Moscow Mills, Missouri

Probable cause

The flight instructor’s delayed remedial action to correct the student pilot’s use of an excessive descent rate during a practice autorotation, which resulted in a hard landing.

NTSB analysis

The flight instructor reported that, about 1 hour into the instructional flight, the student pilot began to perform a practice 180-degree autorotation. While the helicopter was about 100 ft above ground level, the flight instructor noted that the helicopter was descending at an excessive rate, so he took the flight controls and added power in an attempt to flare the helicopter before it touched down. However, the flight instructor was unable to arrest the descent rate, and the helicopter impacted the ground hard. Examination of the helicopter revealed no mechanical anomalies that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for CEN14LA313 for the full record.