Boeing and All Nippon Airways (ANA) are investigating a landing gear problem on the 787 Dreamliner, the first technical glitch reported since the new jetliner entered service less than two weeks ago, the airline said on Monday.
Pilots on the first of two aircraft delivered so far to ANA were forced to deploy the landing gear using a manual backup system, after an indicator lamp suggested the wheels were not properly down.
They landed at Okayama at the second attempt following the incident which happened on Sunday, the airline said.
"We are not yet sure what the problem was, but we are investigating," an airline spokesman said, adding that Boeing is also involved in the investigation.
Kyodo news agency linked the problem to a hydraulic valve.
A Boeing spokesman in Europe said: "We are aware of this matter and are on site in Japan with ANA offering whatever assistance they require."
The 787 Dreamliner is a revolutionary lightweight aircraft built mainly of carbon composites designed to save fuel.
It was delivered in September after three years of production delays and made an inaugural flight on Oct. 26 from Tokyo to Hong Kong followed by regular services from Nov. 1.
ANA has said it will fly the aircraft domestically on a trial basis before putting it on long international routes.
The incident comes days after a Boeing 767 landed on its belly in Warsaw after the landing gear failed to deploy.
The wheels-up landing was hailed as a miraculous escape for 230 people on board, but aviation experts say such incidents are relatively rare.
There are have been 10 accidents involving stuck landing wheels since 2000, none of them fatal, according to a database run by the Flight Safety Foundation.
The landing gear for the 787 Dreamliner is made by Messier-Dowty. Parent Safran declined to comment.