An engine on an A380 belonging to Australian airline Qantas partially disintegrated mid flight earlier this month [AFP]

Up to half of the Rolls Royce engines of the type that disintegrated on an A380 airliner this month may need to be replaced by Australian, Singaporean and German airlines that use them, the Qantas chief executive has said.

Alan Joyce said on Thursday that the British enginemaker had indicated that up to 40 of the engines may need to be replaced.

"Rolls-Royce are still working through the criteria for which engines need to be changed," he said in Sydney.

Rolls Royce's move comes weeks after an engine partial disintegration mid-flight earlier this month forced a Qantas A380 jet with hundreds of passengers on board to make an emergency landing in Singapore.

A spokesman for Airbus, the maker of A380 planes, said in Singapore: "I can confirm that Rolls-Royce is arranging to supply some new engines from the production line to replace some engines removed from the serviced aircraft."

The Airbus A380, which cost $16.3bn to develop but has struggled to attract airlines in major markets, is the world's largest passenger aircraft with an average list price of about $350m.

Peter Harbison, the executive chairman for the Centre for Asia Pacific Aviation, told Al Jazeera that Rolls Royce's move is "still something that's obviously reflecting fairly badly on the manufacturer".

"It's rather uncertain what's exactly involved [in replacing the engines]," he said.

"If it's replacement of 40 engines, that's a big and time-consuming production. If it's modification, then it's not quite such an issue, as long as they get it right this time."

Rolls Royce's move could be another blow to a much-delayed A380 programme as Airbus was scheduled to deliver over a dozen Rolls Royce-powered A380s - primarily to Singapore Airlines, Qantas and Lufthansa by the end of next year.

But both Singapore Airlines and Qantas, with a combined 22 A380s still to be delivered, said on Tuesday they had not been informed of any delivery delays.

Customer reaction

Laurence Barron, Airbus's China chief, said the first delivery to China Southern Airlines Co Ltd, China's first A380 customer, would also go ahead as planned for next summer.

Airlines using the Rolls Royce Trent 900 engines have been ordered by European aviation authorities to undertake major tests, which analysts said were so strenuous they would likely disrupt schedules.

Shares in Rolls Royce, which on Friday said fixing the fault would lead to only slightly slower profit growth, have suffered during its probe.

They were 0.2 per cent down at 596.50 pence by 1130 GMT on Tuesday, around 9 per cent below their last trade before the Qantas incident.

Airbus parent EADS has lost five per cent since the incident and hit a one-month low on Monday. Its shares were 1.3 percent down at 17.78 euros.

Qantas is down 4.9 per cent since the incident.

"I suppose with an issue as complicated as this, Rolls Royce has no choice [but to ask Airbus to return some A380 engines]", Howard Wheeldon, a BGC Partners analyst, said.

He said there would "definitely be a financial hit" for Rolls Royce because of the move.

Airbus said last week that the problem with the Rolls Royce engine could have an impact on its earnings and delivery target for 2011 but did not give details, and airlines contacted on Tuesday had no knowledge of delivery timetable changes.

Source: Al Jazeera and agencies