Incident Details
During approach to the destination, the pilot experienced a variation in engine power and a low rotor RPM indication. In response, the pilot elected to perform an autorotation onto a taxiway. However, upon observing someone in the intended landing area, the pilot maneuvered the helicopter to land in a grassy area instead.
Sequence of Events
During the run-on landing, the helicopter encountered soft terrain and rocked forward. As the helicopter rocked forward, the main rotor blades struck the tail boom, severing the tail rotor assembly. The helicopter came to rest after the strike.
Subsequent Findings
Following the incident, an operational check of the engine was conducted. The engine ran normally during the check, and no reason was found for the reported variation of engine power and low rotor RPM.