Power loss involving a Robinson R44, VH-ZON, 11 km north-north-east of Arkaroola (ALA), South Australia, on 15 July 2013

On 15 July 2013, at about 1500 Central Standard Time, a Robinson R44 helicopter, registered VH-ZON (ZON), departed from the helipad at Arkaroola, South Australia on a short scenic flight. On board were the pilot and two passengers.

During the return leg, when only a few minutes from the helipad, the pilot heard a loud noise from the rear of the helicopter. The helicopter yawed to right and began to descend. The helicopter did not respond to the pilot’s attempt to correct the yaw, so he conducted an autorotation onto a suitable area in the rugged terrain. The helicopter touched down on the rocky ridge and sustained substantial damage. The pilot and passengers did not sustain any injury.

An engineering report found the left magneto had failed. The Civil Aviation Safety Authority (CASA) is aware of the existing problem with Teledyne Continental Motors and Champion Aerospace (Slick) magnetos. A search of the CASA Service Difficulty Report (SDR) database over the 24 months to June 2013 revealed nearly 45 per cent of ignition failures were attributed to magneto failures.

This accident also highlights the importance of thorough pre-flight safety briefs as conducted by the pilot in this situation. The ATSB safety research and analysis report B20040238, Public Attitudes, Perceptions and Behaviours towards Cabin Safety Communications, stated that when safety briefs are thoroughly and professionally delivered, the chances of survival for passengers increase.

Aviation Short Investigation Bulletin - Issue 23