Incident
A flight instructor and student were conducting autorotation landings in an open field. During one approach, the instructor attempted to recover by applying power, but the engine did not produce enough power. The helicopter subsequently landed hard, and the main rotor struck the tail boom, separating approximately half of the boom from the rest of the helicopter.
Investigation
An FAA inspector and an FAA-licensed company mechanic examined the helicopter and performed a static power test on the engine. The test lasted about 15 minutes, with the engine operating at idle and at full power. No abnormalities were observed during the test. Additionally, the fuel filter was inspected and showed no evidence of contamination.
No further details about the helicopter type, registration, or occupants were provided in the report.