Rolls Royce engine on Qantas A380 had manufacturing defect: ATSB

Australian investigators yesterday identified the source of an oil leak that led to the engine of a superjumbo to blow apart in mid air last month, and said it was a manufacturing defect in the Rolls-Royce engine that was to blame. They warned airlines that the potential flaw could result in engine failure.

According to the Australian Transport Safety Bureau (ATSB), the three airlines using Rolls-Royce's massive Trent 900 engines on their A380s need to go back and conduct more checks now that it had identified the problem area. Currently 20 such planes are in services which are being flown by three airlines.

According to an earlier warning, an oil leak was responsible for a fire and subsequent chain of failures, resulting in heavy parts flying off an engine on a Qantas A380 shortly after take off from Singapore on 4 November. Analysts say this is the most safety problem for the world's largest and newest jetliner.

Adding some more specifics, the ATSB which is leading the international investigation into the Qantas breakup, said a section of an oil tube that connects the high-pressure and intermediate-pressure bearing structures of the engine was the danger area.

"The problem relates to the potential for misaligned oil pipe counter-boring, which could lead to fatigue cracking, oil leakage and potential engine failure from an oil fire," the ATSB said in a brief statement.

In counterboring a larger hole is placed over a smaller hole to make room for a seal. According to the ATSB, a misalignment of those holes had caused a thinning of the oil pipe wall and fatigue cracks that could possibly have led to oil leaking into a section of the engine containing extremely hot gas -- a mixture of burned fuel and air. When oil comes in contact with hot gas it burns.