Japan Airlines Co (JAL) <9201.T> said on Sunday that a Boeing Co 787 Dreamliner jet undergoing checks in Tokyo following a fuel leak at Boston airport last week had leaked fuel during tests earlier in the day.
An open valve on the aircraft caused fuel to leak from a nozzle on the left wing used to remove fuel, a company spokeswoman said. The jet is out of service after spilling about 40 gallons of fuel onto the airport taxiway in Boston due to a separate valve-related problem.
In Boston, a different valve on the plane opened, causing fuel to flow from the centre tank to the left main tank. When that tank filled up, it overflowed into a surge tank and out through a vent.
The causes of both the incidents are unknown, the JAL spokeswoman added.
There is no timetable for the plane to return to service.
On Friday, the U.S. government ordered a wide-ranging review of Boeing's 787 Dreamliner, citing concern over a fire and other problems, but insisted the passenger jet was still safe to fly.
JAL and local rival All Nippon Airways Co <9202.T> fly 24 of the 49 Dreamliners delivered to end-December.