Summary
The aircraft took off from Runway 10 at Coffs Harbour and commenced to climb in an easterly direction.
At an altitude of about 300 feet, there was an abnormal engine noise and the pilot commenced a left hand turn with the intention of returning for a landing. Very shortly after the turn was commenced a substantial reduction of
engine power occurred and, in preparation for a forced landing, the pilot discontinued the turn and headed towards
what he believed to be a clear area. The pilot raised the nose of the aircraft as it descended and eventually
crashed into trees situated some 400 metres east-north-east of the upwind end of the runway from which it departed.
A detailed examination of the aircraft wreckage, including the engine, was carried out. It was found that
all the main engine bearing shells exhibited evidence of fretting on the outer surfaces as a result of micromovement within the crankcase halves and, at some considerable operating time prior to the accident, bearing
metal pick-up had occurred in the rear half of the front main bearing. It is unlikely that the condition of the
bearings would have resulted in any significant resistance to engine rotation.
