TOKYO: All Nippon Airways (ANA) said on Monday it was having five Boeing 787 Dreamliner jets repaired for an engine defect, the latest problem to hit the troubled airliner.
The Japanese carrier grounded the planes following an announcement last week by the Dreamliner's engine manufacturer Rolls-Royce about a problem in its gearbox, a spokeswoman said.
"We've exchanged a total of seven engines in five aircraft, cancelling two domestic flights," she told AFP on Monday.
ANA said it immediately suspended service for two of the planes so the parts could be replaced, while it grounded another three after Boeing said more of the planes were at risk.
Two jets have since returned to service, the ANA spokeswoman said, adding that Rolls-Royce discovered the defect - corrosion inside the gearbox - during endurance tests.
"We have identified that a component on Trent 1000 engines fitted to Boeing 787 Dreamliners has a reduced service life," said a Rolls-Royce spokesman in Singapore, adding that no other airlines had been affected.
"This component is being replaced in a number of engines. We are working hard to minimise disruption to customer operations."
In February, Boeing said around 55 of its flagship Dreamliners were at risk of developing a fuselage problem and the jet had suffered severe production delays.
Built largely with lightweight composite materials, Boeing says the Dreamliner is about 20 percent more fuel efficient than similarly sized aircraft and is the first mid-size airplane capable of flying long-range routes.