Sunday, January 20, 2013

Probe of Boeing 787 Battery Fire Expands

Updated January 20, 2013, 11:27 a.m. ET
 

By ANDY PASZTOR and JON OSTROWER
The Wall Street Journal

The National Transportation Safety Board Sunday added a new twist to the high-profile probes of electrical malfunctions aboard a pair of Boeing Co.'s 787 airliners by disclosing that the battery that caught fire on a parked Japan Airlines Co. jet earlier this month "did not exceed its designed voltage."

Japanese investigators looking into the cause of a second lithium-ion battery malfunction aboard an All Nippon Airways Co. 787, which occurred a little more than a week later, have indicated the battery in that incident may have been overcharged, leading to an emergency landing after pilots noticed a burning smell. They also have suggested similarities between the two incidents could help experts quickly get to the bottom of what happened.

The safety board's update, released early Sunday, suggests different circumstances may have preceded the two incidents and that at least to some extent, the investigations surprisingly may be headed in divergent directions.

If that is the case, it may complicate efforts to determine the root cause of the two incidents and potentially delay Boeing's effort to persuade regulators to allow the planes back into service.

Both batteries were heavily charred, according to previously released images. The Federal Aviation Administration last week said both batteries leaked electrolyte fluid and resulted in smoke damage to nearby portions of the aircraft.

U.S. and Japanese safety experts have been working together and sharing preliminary information, though their investigations are being run separately. It is too early to draw definitive conclusions, according to people familiar with both probes, and FAA officials are waiting for more data and analysis before agreeing on interim safeguards to allow 787 Dreamliners back in the air.

The NTSB's latest release, while highlighting the breadth and depth of its investigation, doesn't appear to resolve the most pressing questions.

The safety board disclosed that a team of investigators, including industry experts, are conducting detailed examinations of the internal structure of the battery in the JAL incident, which caught fire while it was being recharged on Jan. 7 at Boston's Logan International Airport following a flight from Tokyo. Various high-tech scans of the battery, and disassembly of a number of cells, appear intended to help investigators determine whether some type of internal fault or manufacturing defect prompted the battery to overheat and start the fire.

As part of its expanding probe, the safety board also is looking at external factors. On Sunday it said investigators already have examined wiring, circuit boards and other battery-related components removed from the aircraft. Investigators also intend to test components that feed power into the battery, according to the update.

On Tuesday, according to the NTSB, a group of safety experts will meet in Arizona "to test and examine the battery charger," which is manufactured there by Secureplane Technologies Inc., a unit of Meggitt PLC.

The safety board took the unusual step of releasing an update to its 787 investigation just after midnight, during a three-day weekend including a federal holiday. The world-wide grounding of Boeing 787s is now stretching into its fifth day, as the company and U.S. and Japanese investigators work to find the causes of the two incidents.

The NTSB also said that certain parts removed from the JAL 787 have been sent to Boeing for analysis and download of data at the company's facilities, a step that could assist the Chicago plane maker in developing potential interim safeguards needed to return the fleet to service. Previously, Boeing officials expressed frustration that some data gathered by government investigators hadn't yet been provided to the company.

When the FAA last Wednesday ordered the 787 fleet in the U.S. grounded, the emergency directive effectively put a halt to all deliveries of new Dreamliners because Boeing is prohibited from conducting test flights of yet-to-be-delivered 787s. Boeing formally announced a moratorium on Dreamliner deliveries Friday. 


Source:  http://online.wsj.com

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