Helicopter Damaged in Hard Landing Following Loss of Engine Power (N2756A)

Incident Details

A helicopter sustained substantial damage during a hard landing following a loss of engine power. According to the operator, the accident occurred during a training flight when a check airman initiated a simulated engine failure. The pilot lowered the collective and entered an autorotation. When the throttle was advanced to recover from the autorotation, the engine out annunciator light illuminated. A full autorotation was then performed, which terminated in a hard landing. The main rotor subsequently contacted the tail boom, severing it.

Investigation Findings

Engine test runs conducted after the accident revealed that the engine could not reach 100 percent power, remaining at 95 to 98 percent (cruise) power. The fuel control unit and power turbine governor units were tested according to current production test specifications. Minor anomalies to the test requirements were observed on both units; however, none of the anomalies were consistent with a loss of engine power. The post-accident inspection and testing did not reveal any conditions that would have precluded sustained engine operation.