On 16 October 2011 at 1033 Coordinated Universal Time, a Boeing Company 747-438 aircraft registered VH-OJS, operated by Qantas Airways departed Suvarnabhumi Airport, Bangkok, Thailand on a scheduled passenger flight to Sydney, Australia. Shortly after takeoff, the flight crew reported hearing a loud bang and experiencing vibrations and abnormal indications from the No.3 engine. The flight crew shut the engine down and declared a PAN before returning the aircraft safely to Bangkok.
Disassembly and inspection of the engine revealed that the engine failure was as a result of the release of a single, stage 7, intermediate pressure compressor blade from the compressor disc slot. The factors contributing to the blade release are the subject of an ongoing investigation by the engine manufacturer. If further information becomes available relating to the engine failure, the ATSB will update this report.