Hughes 269A, VH-HOR, 15 km north-west of Yuendumu, Northern Territory, on 12 July 1990

Circumstances:

The helicopter was engaged in cattle mustering operations. Whilst in level flight at an altitude of 200 feet, the pilot heard a loud noise and felt severe vibration from the engine, which subsequently failed. Following autorotation to ground impact, the aircraft rolled onto its side. The semi-conscious pilot was assisted from the wreckage by the passenger who had evacuated the cockpit unassisted. Strip examination revealed that the engine had failed due to broken conrod bolts and a separated conrod big-end cap from the No. 4 cylinder conrod assembly. This had resulted in internal mechanical damage sufficient to stop the engine.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Conrod bolt failure.

2. Loss of control during the landing. This accident was not the subject of an on-scene investigation.