Has Submitted Applications For Permission To Test Potential Battery Fixes

In what may be the first breakthrough in a return to flight for Boeing's Dreamliners, the planemaker has asked the FAA to allow it to begin conducting test flights with the airplane to evaluate potential fixes for battery issues.

Reuters relays a report from the Seattle Times that Boeing had submitted an application to the FAA seeking permission for the test flights. The entire Dreamliner fleet was grounded last month after a series of incidents involving the airliners' lithium-ion batteries, including one that caught fire on a JAL Dreamliner parked at a gate at Boston Logan International Airport. The request seems to indicate that Boeing at least has an idea about how to correct the problem.

The paper indicated that the FAA was "evaluating" Boeing's request, and while the agency had not set a date for testing to begin, sources said it could be this week. But that could still mean that it might be weeks or months before Dreamliners could begin carrying passengers again.

In its most recent update, the NTSB said that the auxiliary power unit battery, manufactured by GS Yuasa, was the original battery delivered with the airplane on December 20, 2012. The Boards' investigators were made aware of reports of prior battery replacements on aircraft in the 787 fleet, early in the investigation. As reported last week, Boeing, a party to the investigation, is providing pertinent fleet information which investigators will review to determine if there is any relevance to the JAL investigation.

An investigative group continued to interpret data from the two digital flight data recorders on the aircraft, and is examining recorded signals to determine if they might yield additional information about the performance of the battery and the operation of the charging system.

Next week, the NTSB battery testing team will initiate a non-invasive "soft short" test of all cells of the exemplar battery. This test will reveal the presence of any high resistance, small or "soft" shorts within a cell. Also, an NTSB investigator will travel to France with the battery contactor from the JAL event battery, for examination at the manufacturer. The battery contactor connects a wiring bundle from the airplane to the battery.

(Pictured: NTSB investigators and Boeing engineers examine the type of lithium ion battery used on the Boeing 787 to start the auxiliary power unit and to provide backup power for flight critical systems. NTSB Photo)

FMi: www.faa.gov, www.ntsb.gov