Robinson Helicopter Company R22 N28VH accident near Bozeman, Montana

Probable cause

The flight instructor’s unstabilized autorotation, which resulted in a hard landing.

NTSB analysis

According to the helicopter flight instructor, he was demonstrating simulated 180° right turn autorotations. He reported that, during the entry of the third autorotation, the helicopter attitude was excessively nose low and the descent rate was high. He initiated a power-on recovery; however, the flare was initiated too late. He applied forward cyclic to level the skids and increased collective to its mechanical limit, but the helicopter touched down hard, and one of the main rotor blades struck the tailboom.

The helicopter sustained substantial damage to the tailboom.

The pilot reported in the National Transportation Safety Board's Pilot Aircraft Accident Report, "The event could have been avoided by recovering the autorotation sooner and doing a go-around."

The operator reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for GAA17CA434 for the full record.