Japan Finds No Problems at 787’s Battery Supplier

The International Herald Tribune

January 29, 2013

Japanese investigators studying the potentially flammable batteries that have grounded Boeing's 787 fleet wrapped up an on-site inspection at the batteries' manufacturer on Monday and said they would continue their inquiry at a maker of a device that monitors the batteries.

The Japanese Ministry of Transport said that for now, investigators had found no quality-control problems during an eight-day investigation at GS Yuasa, the Japanese company that supplies the 787's lithium-ion batteries, which are at the center of the inquiry. But officials said that the cause of recent battery malfunctions was still unknown and that GS Yuasa remained under investigation.

A lithium-ion battery overheated during a flight in Japan this month on a 787 operated by All Nippon Airways, prompting an emergency landing. That incident came days after another GS Yuasa battery aboard a parked Japan Airlines 787 caught fire at Logan International Airport in Boston. The incidents have prompted regulators worldwide to ground all 787s, and led Boeing to halt deliveries of the aircraft, nicknamed the Dreamliner.

It is still unclear whether problems lie with the batteries themselves or with another part of the plane's complex electrical system. On Monday, the Ministry of Transport said inspectors would start checks at Kanto Aircraft Instrument, which makes a monitoring unit that detects voltage, current, temperature and other vital parameters for the lithium-ion batteries aboard the 787.

''We do not know where the problems lie, so we are simply doing checks in order,'' said an official at the ministry's Civil Aviation Bureau who declined to be quoted by name, citing protocol. It was too early to say that GS Yuasa was off the hook or that inspectors would not be back at the battery maker for more checks, he said. ''We have seen what we needed to see for now, and are moving on, but that does not mean that there was definitely no problem with the battery,'' the official said.

He said that at Kanto, officials would check manufacturing processes to make sure there were no quality control breaches. Kanto executives could not immediately be reached for comment. GS Yuasa said it could not comment on investigations in progress.

The U.S. National Transportation Safety Board, which is also investigating the batteries, has already completed an examination of the monitoring unit at Kanto, which is in Fujisawa, near Tokyo. The U.S.-led team, which also included Japanese officials, examined circuit boards that monitor the batteries and found the boards damaged, which limited the information the team could obtain. The team ''found no significant discoveries,'' the board said in a statement.

Plagued by production delays, the 787 finally went into service last year. The next-generation aircraft is made from lightweight composite materials that improve the jet's fuel efficiency. The 787 also relies on electrical systems far more than do current aircraft, including lithium-ion batteries, which are lighter but are more prone to overheating.

The Japanese government stepped in to give the plane and its made-in-Japan technology a boost in 2008 by easing safety regulations, fast-tracking the rollout of the groundbreaking jet for the biggest Japanese airlines, according to records and participants in the process, Reuters reported.

''I believe the request for the changes came initially from the airlines,'' Masatoshi Harigae, head of aviation at Japan's Aerospace Exploration Agency, told the news service. ''Ultimately, it was a discussion of measures to lower operating costs for the airlines.''

There is no suggestion that easing regulatory standards contributed to the problems facing the Dreamliner, and the looser regulations did not specifically address the risk of the plane's batteries catching fire.