Fatigue cracking caused by the axial misalignment of an area of counter‑boring within the inner diameter of a stub pipe appears to be the cause of an engine failure on a Qantas A380 jet flying from Singapore to Sydney, Australia Nov. 4.
That’s the observation of a preliminary investigation by the Australian Transport Safety Bureau.
The misalignment produced a localized thinning of the pipe wall on one side, leading to a fatigue crack that spilled oil into a combustion chamber of the jet engine. That caused an explosion that splintered a turbine disc which subsequently damaged hte plane’s left wing and fuselage.
Qantas is still testing other Trent engines to see if they also have the defect. The fatigue cracks were discovered in testing at a Rolls-Royce facility in Derby, United Kingdom.
There were no reported injuries to the crew or passengers on the aircraft, which was able to land safely. There were reports of minor injuries to two persons on Batam Island, Indonesia.
The investigation is continuing.
Photo shows detail of combustion chamber oil pipe with misaligned counter-bore.
Source: Australian Transport Safety Bureau