Cathay Pacific said it will resume full operations by Saturday after replacing defective engine fuel lines on its Airbus A350 planes, a problem that had forced it to cancel dozens of flights this week.
Hong Kong-based Cathay, one of the largest operators worldwide of the A350 jetliner, grounded 48 planes for checks on Monday after a Zurich-bound flight had to return to the city shortly after take-off.
The inspection found that components on 15 of the A350s -- whose engines are powered by British manufacturer Rolls-Royce -- had to be replaced.
"Fifteen aircraft were identified with engine fuel lines that require replacement. Of these, six have already undergone successful repairs and are cleared to operate," it said in a statement.
"The remaining nine aircraft will be repaired and are expected to resume operation by Saturday."
When Cathay had initially raised the alarm Monday, it said "the component was the first of its type to suffer such failure on any A350 aircraft worldwide".
The incident prompted other airlines in the region to carry out similar checks on their A350-900 and A350-1000 models.
Cathay so far have cancelled 90 flights between Monday to Saturday, with mainly regional routes including connections to Singapore, Taipei, Tokyo, and Bangkok hit.
Aboard a Cathay A350-900 plane to San Francisco on Wednesday, a Hong Kong passenger surnamed Yuen told AFP that he was "worried but I don't know who I can ask whether this aircraft has been checked".
"I thought it would be cancelled but it wasn't," Yuen texted from the runway.
"I would feel better if Cathay could send us a message saying the plane has been checked but they never did that."
Japan Airlines confirmed that three of their A350 jets turned up no issues, while two more were undergoing inspections Wednesday.
A Thai Airways spokesperson said on Wednesday no problems were found after they inspected their 23-plane fleet of A350s, and the airline was using their planes as normal.
Singapore Airlines said on Tuesday that they were also carrying out checks but that there was "no impact" on flights operating with their A350-900 fleet.
Airbus and Rolls-Royce have so far declined to provide details, saying an ongoing investigation prevents them from commenting further.
Terence Fan, an aviation expert at Singapore Management University, said the Airbus 350 planes had an "airworthiness directive" issued on them by the European Union Aviation Safety Agency this year.
"A350 is often deployed in long-haul flights, many of which traverse oceans or sparsely populated areas with few airports for the affected aircraft to immediately divert to if both engines lose power as a result of reduced fuel intake," he said.
"Clearly, the impairment was not to this extent at this point, but certainly sufficient to abort that flight to Zurich."
Last November, Emirates chief executive Tim Clark expressed concerns about the durability and longevity of A350 engines.
Rolls-Royce has defended its Trent XWB-97 engines and said it was taking steps to improve their durability.
