A line of Boeing 787 jets are parked at Paine Field Tuesday, Feb. 5, 2013, in Everett, Wash. Federal regulators say they are evaluating a Boeing request to conduct test flights of its 787 Dreamliners, which were grounded nearly three weeks ago after a battery fire in one plane and smoke in another. The Federal Aviation Administration confirmed the request, but officials declined to elaborate. (AP Photo/Elaine Thompson)
Updated: March 8, 2013 7:36AM
WASHINGTON — National Transportation Safety Board investigators are looking into the special conditions the Federal Aviation Administration required Boeing to meet in order to use lithium ion batteries to power the 787’s electrical systems, the nation’s top aviation safety investigator said Wednesday. At the same time, Boeing is proposing changes to its battery design to minimize the risk of fire while it searches for a long-term solution, according to the Wall Street Journal, which quotes unnamed sources.
Also Wednseday, Boeing received permission from the Federal Aviation Administration to fly one of its 787s from Fort Worth, Texas, to Everett, Wash., on Thursday. The permission is for a single flight for the purpose of relocating the plane, and is not a test flight, the FAA said in a statement. The FAA is still considering a separate Boeing request to conduct test flights, the agency said.
Boeing Co. spokesman Marc Birtel said that Boeing is still trying to find the cause of the battery incidents. “We are confident — as is the FAA — that the 787 is safe to operate for this activity. Safety of the crew on board is our top priority,” he said in a statement.
Investigators have been working very closely with the FAA on a review the agency has under way of its sanctioning of the 787’s certification for flight, Hersman said. The FAA awarded the certification in August 2011.
A government-industry advisory board that works closely with the FAA issued testing standards for lithium batteries used in aircraft operations several months after the agency had approved a separate testing regime for the 787’s batteries.
“What happens is that when an aircraft is certified it basically gets locked into the standards that were in existence at the time,” said NTSB Chairman Deborah Hersman. Oftentimes, tougher standards will come along later, but aren’t applied to already-approved aircraft designs. “Those are issues we do look at regularly in our investigations and it is something I’m sure we will be focusing on with the battery.”
“We are evaluating assessments that were made, whether or not those assessments were accurate, whether they were complied with and whether more needs to be done,” she said. “I think that is important before this airplane is back in the air, to really understand what the risks are and that they’re mitigated effectively.”
The use of lithium ion batteries to power aircraft systems isn’t necessarily unsafe despite a battery fire in one Boeing 787 Dreamliner and smoke in another, but manufacturers need to build in reliable safeguards, Hersman said.
Hersman said she doesn’t want to “categorically” rule out the use of lithium ion batteries to power aircraft systems, even though it’s clear that safeguards failed in the case of a Japan Airlines 787 that had a battery fire Jan. 7 while parked at Boston’s Logan International Airport last month.
Nine days after the battery fire in Boston, another battery overheated on an All Nippon Airways 787, leading to an emergency landing in Japan. The same day, FAA officials ordered U.S. carriers with 787s — there’s only one, United Airlines, with six planes — to ground the planes. Aviation authorities in other countries swiftly followed suit. In all, 50 planes operated by seven airlines in six countries are grounded.
“Obviously what we saw in the 787 battery fire in Boston shows us there were some risks that were not mitigated, that were not addressed,” Hersman told reporters in an interview. “We need to understand what happened.”
The board is still weeks away from determining the cause of that battery fire, she said.
The 787 is the first airliner to make extensive use of lithium batteries. Aircraft makers view lithium batteries, which are lighter and can store more energy than other types of batteries of an equivalent size, as an important way to save on fuel costs. The Airbus A350, expected to be ready next year, will also make extensive use of lithium ion batteries. Manufacturers are also looking to retrofit existing planes, replacing other types of batteries with lithium ion.
But lithium batteries are more likely to short circuit and start a fire than other batteries if they are damaged, if there is a manufacturing flaw or if they are exposed to excessive heat.