Australian investigators yesterday said an oil leak may have caused an engine blast on a Qantas Airbus A380 that badly damaged the plane, but were satisfied with the actions taken to prevent it happening again.
In a preliminary report, the Australian Transport Safety Bureau said a possible manufacturing issue related to the oil pipes on the Rolls-Royce Trent 900 engine could have caused the scare on last month’s flight out of Singapore.
The safety watchdog said the problem could lead to fatigue cracking, oil leakage and potential engine failure from an oil fire.
“We are yet at the stage where we can definitively say that the potential fatigue problem with the oil pipe that has been detected is the cause of what happened,” said Martin Dolan, the bureau’s chief commissioner.
“But it was significant enough ... that it needed to be identified and it has been safely dealt with,” he said.
The bureau’s preliminary report, the investigators’ first into the incident, was released a day after the watchdog issued an urgent safety recommendation warning of a “critical safety issue” with the Rolls-Royce engines’ oil pipe.
Dolan said Rolls-Royce had agreed to the bureau’s directive issued on Thursday to address the issue, but added that the engines would be taken out of service if the embattled British company detected the same issue again.
The bureau said it was also satisfied with the actions taken by Qantas since the incident — which prompted the Australian carrier to ground its six A380s for three weeks as investigations into the long-haul aircraft were carried out.
In addition, the European Aviation Safety Agency had decided to upgrade the engine’s control software to detect any problems earlier and ensure the engine would be shut down before it could explode, Dolan said.
“We’re still in the early stages of investigation, but significant action has already been taken to minimise the risk of a recurrence,” he said.
Qantas, which has flagged possible legal action against Rolls-Royce if no commercial settlement is reached over the Nov. 4 incident, welcomed the report.
It has brought two of its A380s back into service but barred them from flying Australia-Los Angeles because that route requires greater engine thrust. It said it had inspected the oil pipes on both planes and found no problems.
Dolan said the initial assessment was that an oil leak had caused a fire, which caused the turbine to break up, raining pieces down on an Indonesian island and into the double-decker plane itself.
Inspections of engines for oil leakages were then carried out ,but extra checks over the past 48 hours had prompted the safety recommendation to Rolls-Royce over potential manufacturing defects in oil pipes — internal elements of the engines that would have been difficult to access and inspect.
The preliminary report says sections of the fractured disc and other engine components smashed into the aircraft’s left wing and a number of other areas, resulting in “significant structural and systems damage”.
Dolan praised the Qantas pilots who managed to bring the damaged Sydney-bound plane back to Singapore trailing smoke and safely land it without injury to any of the 469 passengers and crew on board.
“The aircraft would not have arrived safely in Singapore without the focused and effective action of the flight crew,” he told reporters in Canberra.