Qantas Airways chief executive Alan Joyce has said an engine failure on an A380 superjumbo should be blamed on the engine's design and had nothing to do with the airline's operations.

A mid-flight failure of a Rolls-Royce Trent 900 engine on November 4 forced Qantas to ground its six-plane A380 fleet. On Saturday, the airline resumed some A380 operations but four of the planes remain grounded.

Joyce told the Australian Broadcasting Corporation (ABC)  in an interview broadcast on Sunday that his airline performed  'exceptionally well' over the incident, which forced an A380  with 459 on board to make an emergency landing in Singapore.

'It was a new engine and it was absolutely clear nothing to do with anything Qantas was doing,' Joyce told Inside  Business in a recorded interview. 'It was an engine that  didn't perform to the parameters that we would've expected.'

Although he admitted the bill was 'still mounting', he  said that Qantas' handling of the incident had probably  enhanced its brand rather than damaged it.

'In the research we're doing, people are aware that this  was a Rolls-Royce problem, so that when we survey the general  population the vast majority of people know that there's a  problem with the design of the engines,' he said.

Joyce dismissed several other incidents involving  turn-backs of Qantas planes since November 4 as minor in  global aviation terms, saying there were 'hundreds of them  that take place every year'.

'It's how you handle them, and how you manage them,' he  said. 'And each one of these when I look at them I can see  that Qantas performed exceptionally well in how it managed  them.'

Safety remained the airline's top priority, he said.

Joyce said that Qantas was maintaining some restrictions  on its A380s, and they would not yet be operating across the  Pacific to Los Angeles.

The decision not to operate the A380s across the Pacific  had been taken in consultation with Rolls-Royce and Airbus,  Joyce said, as the engines needed to be operated at a higher  power setting for longer distances on that route.

'We introduce the aircraft to make sure that we understand  how the engines are performing before we put them back on LA,'  he said.

The November 4 incident was the most serious so far for  the world's largest passenger aircraft. It hit shares in  Qantas, Airbus parent EADS and Rolls-Royce. – Reuters