All Nippon flies 1st Dreamliner to test for battery glitch

All Nippon Airways (ANA), the Japanese launch customer for Boeing Co's 787, flew its first Dreamliner in more than three months on Sunday to test reinforced batteries installed by the US aircraft maker.

The ANA flight was the second by an airline since aviation regulators on Friday gave permission for 787 operations to restart after batteries on two of them overheated in mid January. One was on an ANA plane in Japan and another on a Japan Airlines jet parked at Boston's Logan airport.

Ethiopian Airlines on Saturday became the world's first carrier to resume flying Dreamliner passenger jets since the global fleet was grounded three months ago, carrying passengers to neighbouring Kenya from Ethiopia.

The ANA flight, with company president Shinichiro Ito and Boeing's chief of commercial aircraft, Ray Conner, among those on board, left Tokyo's Haneda airport at 8.59 am local time. It returned without incident at 10.54 am, a spokesman for the airline said.

ANA plans at least 230 test flights through May before resuming commercial operations. In addition to the battery fix approved by the Federal Aviation Administration (FAA) in the United States, Japan's Civil Aviation Bureau has requested its airlines monitor the battery current while the jet is in the air and inspect used batteries.

ANA owns 17 of the 50 Dreamliners, which have been grounded since mid January, while local rival JAL has seven of the carbon composite aircraft in its fleet.

JAL will start test flying its Dreamliners in early May with the aim of returning to normal operation in June. Neither Japanese carrier, which on Tuesday will release their earnings results for the three months that ended March 31, have said how much the 787 grounding has cost them in lost revenue.