The National Transportation Safety Board held a news conference about the progress on its investigation into the grounded fleet of Boeing 787s.
Investigators said they still don't know why the battery on a Japan Airlines 787 caught fire in Boston and said they're working around the clock to find out.
Boeing has invested billions in the jet, and the futures of the company and many people who live in Western Washington are riding on what investigators find.
The NTSB released a photo of an engineer inspecting the charred battery casing from the Japan Airlines 787 that had a fire on Jan. 7 in Boston.
Engineers have been pulling apart the battery, taking pictures of it and examining each of the battery's electrodes at the National Transportation Safety Board Lab in Washington.
The Safety Board said heat charred all eight of the battery’s lithium-ion cells.
Smoking or burning lithium ion batteries are blamed for fires in cell phones, electric cars and mp3 players as well.
Investigators could be focusing on some wiring inside the battery because they're examining it under a microscope.
Because the fire happened in the U.S., the NTSB is leading the probe. It said the voltage of the battery on the All Nippon Airways plane was just below maximum.
Japan's Space Agency and the battery's manufacturer are now pulling it apart. Officials said the batteries on both planes could have been charged too quickly or components could have been defective.
Two shifts of investigators are working in Japan and in the United States on the problem.
"We are evaluating scenarios, reviewing maintenance records and gathering information collected in recent supplier audits," said NTSB Chairman Deborah Hersman.
Representative Rick Larsen of Everett, who is on the House Aviation Subcommittee, is hopeful the problem won’t take a long-term fix.
“My impression is that this is a short-term issue, that it'll be sooner rather than later for the 787 to get back up in the air,” said Larsen.
But a second overheated battery on an All Nippon Dreamliner last week caused the FAA and other governments to ground all 50 of the jets in the world fleet.
Some have criticized that decision, but Larsen still thinks it was the right thing to do.
“The FAA is on top of it. They made the right decision to ground the airplane, and they're making the right decisions now to make a thorough review of this particular issue,” said Larsen.
So what will it take for the FAA to allow the Dreamliners back in the air?
The FAA hasn't really said yet.
The order that grounded the planes requires an "approved modification" of the batteries, but no one's decided what that modification is.
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