A Qantas Airbus A380 in flight.
A fatigued oil line stemming from "a possible manufacturing issue" is believed to be at the root of an un-contained engine failure on an Australian superjumbo jet last month, according a preliminary report released by Australian investigators Friday.
The Airbus A380 operated by Qantas was forced to make an emergency landing after one of its four Rolls-Royce Trent 900 engines blew apart during a Singapore to Sydney flight on November 4.
The Australian findings suggest that an oil-line leak resulted in a fire that then lead to a catastrophic turbine failure.
A statement released by the ATSB with the preliminary report says:
The report identifies an overspeed-related failure in the intermediate pressure turbine disc in the aircraft's No 2 engine. Sections of the fractured disc and other engine components penetrated the aircraft's left wing and a number of other areas on the aircraft, resulting in significant structural and systems damage to the aircraft.
As a result of the investigation, the ATSB has issued a safety recommendation about potential engine problems in some Airbus A380 aircraft. The problem relates to a possible manufacturing issue with the high pressure/intermediate pressure (HP/IP) bearing structure oil pipes of some engines, which could lead to fatigue cracking, oil leakage and potential engine failure from an oil fire within the HP/IP bearing buffer space.
In response to the recommendation Rolls Royce, affected airlines and safety regulators have taken action to ensure the continued safe operation of A380 aircraft. The action involves the close inspection of affected engines and the removal from service of any engine which displays the suspected problem. In addition, the European Aviation Safety Agency has approved a modification to the engine control software to reduce the risk of an overspeed-related turbine disc failure.
The statement goes on to say:
The report also describes the flight crew's actions in dealing with the consequences of engine failure and in landing the aircraft safely in Singapore without injury to any of the 469 crew and passengers on board.