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SYDNEY -- Australia's national airline is keeping its flagship superjumbos on the ground more than a week after a frightening midair engine disintegration, disrupting its most lucrative long-haul routes even as regulators and pilots say the Rolls-Royce motors are safe.

With its competitors' Airbus A380s back in service, Qantas appears caught between a drive to zealously protect its reputation as the world's safest airline, and the financial imperative to return its six spacious Airbus superjumbos to service on its grueling routes to the U.S. and Europe.

Lufthansa and Singapore Airlines are flying their 14 Airbus A380s again after carrying out extra inspections in the wake of the frightening engine problem on a Qantas flight to Singapore, which revealed a problem of potentially disastrous oil leaks in Rolls-Royce motors on the world's largest jetliner.

"We're not going to rush anybody, we're not going to be putting a deadline on it. We're going to make sure it's absolutely right before we have this aircraft start flying again," CEO Alan Joyce said Saturday at a celebration of the 90th anniversary of his airline, which began as a small-scale flier transporting pastoralists and miners across the northern Outback.

With no fatal crash since it introduced jet-powered planes in the late 1950s, Qantas enjoys a reputation made globally famous by the 1988 movie "Rainman," in which Dustin Hoffman's number-obsessed character insists it is the only airline he will use because "Qantas never crashed."

But a run of scares in a variey of planes in recent years have tarnished that image. The most serious -- when a faulty oxygen tank caused an explosion that blew a 5-foot hole in the fuselage of a Boeing 747-400 over the Philippines -- prompted aviation officials to order Qantas to upgrade maintenance procedures

Then on Nov. 4, leaking oil caught fire in the motor of a four-engine Qantas A380, heating metal parts and causing the disintegration over Indonesia before the jetliner returned safely to Singapore. Experts say chunks of flying metal damaged vital systems in the wing of the Sydney-bound plane, causing the pilots to lose control of the second engine and half of the brake flaps on the damaged wing in a situation far more serious than originally portrayed by the airline.

Qantas grounded its A380s within hours and said four days later that the checks had revealed suspicious oil leaks on three engines on three different grounded A380s.

Singapore Airlines replaced three engines after finding oil leaking in them but did not pull planes from service, saying "ongoing precautionary inspections enable the safe and continuous operation of the fleet."

Lufthansa found no leaks and spokesman Christian Gottschalk said the German carrier would keep flying its A380s, following the grounding of one plane to carry out special checks. He said Lufthansa continues to carry out extra inspections of the engines as recommended by the European Aviation Safety Agency.

"Through this, we feel that we have reached a high level of security on the existing routes," Gottschalk said.

Britain's Rolls-Royce Group PLC, the world's second-largest engine maker, said Friday that it would be replacing an unspecified module, or collection of linked parts, on the Trent 900. Airbus said Rolls-Royce would also be equipping the engines with software to shut them down before an oil leak could cause an engine to disintegrate.

It would be naive to think that Qantas management is not feeling financial pressure to return their A380s to the air, said Martin Chalk, head of the European Cockpit Association, a Brussels-based pilots' union.

"But they know it's not as strong as the pressure of adverse publicity if things go wrong," he said. "Another incident would be much more damaging than the current commercial losses."

Qantas has suffered financially along with other airlines during the global financial crisis, which slashed travel budgets especially in the high-marginal profit areas of business and first class tickets -- where A380s are marketed as state-of-the-art and ultra luxurious. Qantas Airways Ltd. in August posted a 4.3 percent fall in annual profit.

Chalk said that the A380s were "perfectly safe" to fly and Lufthansa was conducting engine checks before each departure as a precautionary measure, even though no problems had been identified so far.