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Time Is Ticking for NTSB Battery Investigation




The NTSB has issued an "urgent" procurement request to have a Maryland company perform computed tomography (CT) scans starting May 6 on as many as 48 Boeing 787 lithium-ion battery cells.

The work signals a rush for the Board to find a root cause for the battery issues that grounded the fleet as airlines begin revenue service with modified 787s this month and into June.

"[The tests] must also be completed within the shortest timeframe possible to provide the fastest possible receipt of this information to avoid potential future accidents involving this type of aircraft battery," says the NTSB in a "sources sought" notice published on May 3. "Since the FAA has recently approved a plan intended to result in the Boeing787 being approved for a return to service, the information from these tests (and the CT scans required to support these tests) is needed as soon as possible," says the NTSB.

The work is expected to take one week, with a final report issued no later than 10 days thereafter.
The request comes two weeks after the FAA on April 19 approved Boeing's fix for the battery problems that grounded the 50-aircraft fleet in January following two battery incidents, one on the ground and one in the air.

At issue are as of yet unexplained thermal runaways that began in one or more cells in the APU battery and spread to adjacent cells. Boeing's fix, which technicians are now installing on the fleet, includes batteries with more insulation between cells and a 1/8th-in.-thick stainless steel battery enclosure with a vent line assembly to dump smoke overboard if a thermal runaway in one cell does occur.

Based on the urgent procurement, the NTSB remains concerned that the root cause of the problem has not been identified, a stance the Board took during a two-day investigative hearing on April 23 and 24 regarding the troubled path to certification for the battery.

In the sources sought notification, the NTSB says it is planning to "conduct teardown examinations as soon as possible" of several aircraft batteries similar to the "one involved in an aircraft incident" as part of its Boston investigation.

Highlighting the continued concern in the aviation industry about lithium-ion battery technology, the NTSB mandated that the contract be issued to a local company, as the cells cannot be shipped via air cargo.