Primary finding
Probable cause
Inadequate fuel quality control procedures by the helicopter operator resulting in fuel contamination and a loss of engine power. The pilot's decision to extend the autorotative glide to avoid striking residential homes, which resulted in low main rotor rpm and a subsequent in-flight loss of control, is also causal in this accident. A factor in the accident was the unsuitable nature of the residential area over which the loss of power occurred for a successful forced landing.