Bell 47G-2A-1 N73905 accident near Livonia, New York

Probable cause

The pilot’s delayed action to arrest the high descent rate during a practice autorotation in tailwind conditions which ultimately resulted in loss of control.

NTSB analysis

During a practice autorotation with a tail wind, the pilot began the maneuver and the helicopter initially lost airspeed; the pilot immediately corrected with forward cyclic input, which also increased his descent rate. The higher than normal descent rate continued, and he began the power recovery earlier than normal. Shortly before touchdown, the pilot noticed a slope in the terrain with the rising side to his aft. The helicopter continued to descend and the helicopter’s tail rotor contacted the ground during the landing flare. The resulting impact resulted in a loss of control and substantial damage to the tail boom and tail rotor. The pilot stated that there were no preimpact malfunctions or failures of the helicopter that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for ERA23LA157 for the full record.