Incident
While en route at an altitude of 400 feet, the pilot heard a loud bang and felt a strong left and right yaw. He subsequently performed an emergency shutdown of the engine and executed an autorotation landing on a beach.
Investigation
Post-accident examination revealed a fracture failure of the no.4 engine bearing. At the time of the event, the roller bearings had accumulated approximately 5,487 hours since their installation in the engine on June 12, 1992. The engine was installed on the helicopter on September 3, 1992.
Findings
The investigation identified the fracture failure of the no.4 engine bearing as the initiating event.