Australia's Qantas Airways has grounded its A380 fleet for at least another three days as it investigates oil leaks as a possible cause of the explosion which tore apart one of the superjumbo's engines last week.
The incident has rattled the global aviation industry which is recovering from heavy losses during the global economic downturn and has been damaging for Rolls-Royce which is developing new engines for the next generation of commercial jets.
Qantas said its six Airbus A380 aircraft would be grounded for at least another 72 hours after an investigation found oil leaks on three Rolls-Royce engines which have been removed from the planes.
Oil leaks in the engines' turbine area were now the focus of the investigation into the incident on 4 November where an engine broke apart above Indonesia's Batam Island, forcing the world's largest passenger plane to make an emergency landing in Singapore.
"We are working with Rolls-Royce to ensure we have an appropriate fix to this issue. Our team, Airbus and Rolls-Royce are working around the clock to ensure that. We are not looking at any other alternatives," chief executive Alan Joyce told reporters.
Singapore Airlines said on Monday it had completed engine inspections all its A380s and did not find any issues of concern. Lufthansa has also been conducting additional tests of its A380 fleet.
Joyce said Qantas had no plans to change its delivery schedule for new A380 planes and it was too early to talk about any legal claim against Rolls-Royce or Airbus.
Qantas has never had a fatal accident since it start flying jetliners.
"For all businesses it is imperative that safety is front of mind when running the business. Qantas has a pretty good track record and they probably get a lot of unwarranted attention," said Jason Teh, portfolio manager at fund manager Investors Mutual.
Thursday's engine failure was the biggest incident to date for the A380, which went into service in 2007 and can carry more than 500 people.
Australian air safety investigators said the recovery of a broken engine disk may be crucial in understanding what caused the A380 engine failure.
The Australian Transport Safety Bureau (ATSB) issued a statement and photograph of the broken disk and called on residents of Indonesia's Batam Island who may have found the parts of the disk among debris to return it to the police.
Joyce said a huge amount of material had already been recovered. "All of this is starting to narrow the investigation back to the oil leak," he said.
* Rolls-Royce said on 8 November that it has "made progress in understanding" the cause of the Qantas engine failure, and that the incident is specific to the Trent 900 engine. The statement was intended to allay investor concerns that similar problems might occur in other Rolls-Royce aircraft engines.