TOKYO--The two largest customers of Boeing Co.'s (BA) Dreamliner
jets said malfunctions had forced them to replace a series of their
planes' batteries, even before serious incidents of battery
overheating led global regulators to ground all of the flagship
787s two weeks ago.
Japan's All Nippon Airways Co. (9202.TO, ALNPY), which operates
17 Dreamliners, said Wednesday that during the roughly 14 months
since it began flying the planes commercially, it replaced 10 of
the lithium-ion batteries that are used to start the engines and
provide auxiliary power--largely because of problems holding
charges or providing sufficient power. That means the carrier
replaced nearly a third of their Dreamliner fleet's batteries
before they had even reached the halfway point before their first
routine maintenance check, which was scheduled at two years, an ANA
spokesman said.
Japan Airlines Co. (9201.TO), which operates seven Dreamliners,
also said it replaced some of its planes' batteries, but was still
checking into frequency and cause.
The primary reasons 787 batteries have been replaced have been
because they were improperly disconnected, they were left to
discharge without any other power sources on the aircraft, causing
a deep discharge, or they expired, said a person familiar with the
issue.
The ANA battery replacements were reported on Tuesday by the New
York Times.
The disclosures come as regulators, who have so far been unable
to pinpoint the cause of the battery problems by examining the
burned units or visiting the companies that made the pieces, are
broadening their probe to look at carriers' maintenance records--
including how often 787 operators in Japan and elsewhere had to
replace suspect or malfunctioning batteries, according to people
familiar with the matter. U.S. experts also are looking to collect
information about unusual charging or discharging incidents
recorded by those carriers, these people said.
The investigators are hoping to shed some light on what caused
batteries on two planes, one operated by ANA and the other by JAL,
to overheat and burn in recent weeks. The incidents led global
regulators to ground all 787s beginning on Jan. 16, until the
batteries can be shown to be safe. Aviation investigators from the
U.S. and Japan have been probing the production process of
Kyoto-based battery maker GS Yuasa Corp. (6674.TO) as well as
makers of the power units' chargers and circuitry in the U.S. and
Japan, but so far have found no obvious problems or defects.
Japanese and U.S. investigators who visited GS Yuasa also
inspected dozens of Dreamliner batteries that had been returned to
the maker--some by carriers--but weren't able to find any
connections with the overheating problem, said transport ministry
official Shigeru Takano. In some cases, the batteries were sent
back to GS Yuasa because they had been completely discharged by
mistake, he said.
In ANA's case, five of the 787 batteries, which use a powerful
but flammable lithium-ion technology that has only recently been
rolled out in commercial airplanes, were replaced because the units
had lost their ability to hold a full charge, said ANA spokesman
Ryosei Nomura. In three other cases, the batteries weren't able to
provide sufficient power to the systems they were connected to. The
reason for replacing the other two batteries wasn't immediately
clear, Mr. Nomura said.
In all but one of the 10 cases, the batteries were part of the
unit that starts the Dreamliner's engines, rather than the unit
that provides auxiliary power. The batteries came from seven
different planes, meaning that three of the aircraft had to get
replacements twice, Mr. Nomura said.
The carrier replaces batteries on its Boeing 777s--one of the
workhorses of its fleet-- at about the same rate, although the 777
batteries use a different nickel-cadmium technology, and are
replaced for a mix of defects and routine maintenance swap-outs,
said Mr. Nomura. The carrier reported the replacements to Boeing,
but didn't at the time tell Japanese authorities because the
incidents didn't rise to the level of seriousness required for such
reports, he said.
"Officially we can't comment as the NTSB has said this is now
part of their investigation," said Boeing spokesman Marc
Birtel.
--Jon Ostrower contributed to this report.
Write to Yoshio Takahashi at Yoshio.Takahashi@dowjones.com,
Yoree Koh at Yoree.Koh@wsj.com and Andy Pasztor at
Andy.Pasztor@wsj.com
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