The ATSB today released its preliminary investigation report into the 30 August 2010 incident involving an Australian operated Boeing 747 aircraft that experienced an engine failure not long after leaving San Francisco, en route to Sydney.
The preliminary report reveals the number 4 (right most) engine sustained an internal mechanical failure in the turbine area, rupturing the casing and ejecting debris that punctured a hole in the cowling. The plane's flaps and wing skin also incurred minor damage.
The initial ATSB investigation centred on gathering the facts associated with the engine failure. This included the inspection of the engine and aircraft in San Francisco, and the later detailed disassembly and technical examination in Hong Kong.
As part of the continuing investigation, the ATSB will examine the circumstances surrounding the release of debris from the engine. While 'uncontained' engine failures are relatively uncommon it is important to ensure the circumstances are examined thoroughly and any significant safety lessons are learnt from the incident.