Incident Description
A helicopter experienced a complete loss of engine power during flight, leading to a forced landing in a residential area. The pilot reported hearing a loud "bang" from the rear of the helicopter, after which all engine power was lost. The pilot performed an autorotation, landing in the backyard of a residence. During the landing, the main rotor struck a garage, causing the helicopter to roll onto its side. Subsequently, a fire broke out and the helicopter was destroyed.
Investigation Findings
An on-scene examination of the helicopter wreckage was conducted. The examination failed to reveal any anomalies that could be attributed to a pre-impact defect. Further detailed inspections were performed on the engine, fuel pump, fuel control unit, and the power turbine governor. These inspections found no defects that would have prevented normal operation. The cause of the engine power loss remains undetermined based on the available evidence.