January 17, 2013 | 18
Boeing’s Dreamliner has likely become a nightmare for the company, its airline customers and regulators worldwide. An inflight lithium-ion battery fire broke out Wednesday on an All Nippon Airways 787 over Japan, forcing an emergency landing. And another battery fire occurred last week aboard a Japan Airlines 787 at Boston’s Logan International Airport. Both battery failures resulted in release of flammable electrolytes, heat damage and smoke on the aircraft, according to the U.S. Federal Aviation Administration (FAA).
The FAA on Wednesday ordered U.S. operators to temporarily ground the aircraft to avoid the risk of additional battery fires. Before any Dreamliners resume flight, operators of U.S.-registered 787s will have to demonstrate to the FAA that the batteries are safe. “These battery problems, if not corrected, could result in damage to critical systems and structures, and the potential for fire in the electrical compartment,” according to a statement issued by the FAA, which says it is investigating. The statement makes no mention of GS Yuasa Corp., the company that makes the 787’s batteries, nor does it call upon Boeing specifically to demonstrate battery safety.
In addition to reviewing the aircraft’s design, manufacture and assembly, the FAA says it also will validate that batteries and the battery system on the aircraft comply with the “special condition” the agency issued as part of the 787’s certification. This condition was that Boeing take a series of protective measures to ensure the batteries wouldn’t fail, causing the exact same problems the company now faces. The 787’s short history has been filled with battery and mechanical problems, as outlined in Patrick Smith’s “Ask the Pilot” January 16 blog post.
The 787 relies on two identical lithium-ion batteries, each about one and a half to two times the size of a typical car battery, The New York Times reported on Thursday. One battery starts the auxiliary power unit (a small tail engine that provides power for the plane while on the ground), and the other starts the pilot’s computer displays and serves as a backup for flight systems.
United Airlines is currently the only U.S. airline operating the 787, with six airplanes in service. All Nippon announced a grounding of all 17 of its Dreamliners on Wednesday, while Japan Airlines has likewise taken its seven 787s out of circulation pending a safety investigation.
Boeing CEO Jim McNerney responded to the FAA directive grounding the 787s with a statement indicating the company is working “around the clock” to help solve the problem and is “confident the 787 is safe.”
The 787 Dreamliner is a midsize aircraft capable of flying longer nonstop routes with cleaner, more humid cabin air pressurized to make passengers feel as though they are at 1,800 meters, instead of the usual 2,400 meters. Such modifications are made possible by the use of carbon fiber, which is stronger, lighter and rust-resistant compared with the typical aluminum fuselage. This strength also enables Boeing to make the aircraft with larger windows that feature electrochromic shading that automatically darkens in bright sunlight. In 2011, after a three-year delay, the 787 became the first commercial aircraft with a shell made primarily of carbon fiber, which promises 20 percent fuel savings for airlines.
Lithium-ion batteries—used to power mobile phones, laptops and electric vehicles—have summoned plenty of controversy during their relatively brief existence. Introduced commercially in 1991, by the mid 2000s they had become infamous for causing fires in laptop computers.
More recently, the plug-in hybrid electric Chevy Volt’s lithium-ion battery packs burst into flames following several National Highway Traffic Safety Administration (NHTSA) tests to measure the vehicle’s ability to protect occupants from injury in a side collision. The NHTSA investigated and concluded in January 2012 that Chevy Volts and other electric vehicles do not pose a greater risk of fire than gasoline-powered vehicles.
GS Yuasa says it may take months to investigate what caused the All Nippon incident, Bloomberg and the Associated Press reported Thursday. The key issue is whether the problem was caused by the battery itself or the electrical system as a whole.
Image of an All Nippon Airways Boeing 787-8 courtesy of hitachiota, via Wikimedia Commons
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