Accident Details
A helicopter was involved in a training accident while practicing autorotations to a power-on recovery. During the maneuver, the pilot attempted to recover engine power, but the engine did not respond as quickly as anticipated. The helicopter made a hard landing, contacting the ground on the rear heels of both skids.
The flight instructor observed that the pilot was late in adding power and attempted to correct the situation, but was unsuccessful. The landing area was a dry riverbed with a surface consisting mostly of soft sand. During the hard landing, the left skid heel struck a log that was embedded in the sand. The impact caused the helicopter to pitch forward onto the skid toes and subsequently roll over onto its left side.
Post-Accident Examination
Both the flight instructor and the pilot reported that there were no problems with the engine during prior autorotations. Following the accident, the engine was still running when the helicopter came to rest. The engine was later removed and run in a test cell, where it met all of the manufacturer's parameters. No discrepancies were found in the control or fuel systems.