NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this public aircraft accident report.
The commercial pilot was conducting a local public flight. He reported that, about 7 minutes into the flight, while the helicopter was orbiting over a fixed area, he noticed the engine and rotor rpm decrease. The pilot rolled the helicopter out of the orbit, and the engine and rotor rpm stabilized momentarily at 97%. The pilot then attempted to increase the engine and rotor rpm while turning the helicopter toward a nearby airport. During the maneuver, the engine and rotor rpm decreased rapidly. The pilot entered an autorotation and executed an emergency landing. The helicopter then landed hard, and the tail impacted the ground and separated from the airframe.
A postaccident examination of the airframe and the engine revealed no anomalies that would have precluded normal operation. During an engine test run, the engine produced rated power. Examination of the fuel system revealed no anomalies, and a fuel sample taken from the helicopter tested positive as jet fuel (Jet A). The reason for the loss of engine power could not be determined.