Pilot Actions
After hearing an unusual noise from the engine, the pilot initiated a precautionary autorotation to land. The maneuver was performed to ensure a safe touchdown given the potential engine issue.
Landing Sequence
The helicopter touched down on uneven terrain in a nose-low attitude. The impact conditions resulted in the main rotor blades making contact with the tail boom. This contact chopped off the tail rotor assembly from the tail boom.
Post-Recovery Examination
Following recovery, the owner/operator examined the helicopter and reported finding no evidence of any pre-existing mechanical failure or anomaly. The owner/operator stated that the damage was consistent solely with a hard landing event, during which the main rotor blades contacted the tail boom, causing it to be severed in two.