As Boeing’s 787 enters the second month of its fleet-wide grounding, the U.S. airframer is poring over data collected on a series of flight and ground tests and says it is making “good progress” toward a solution.
The fix, at least in the short term, continues to be focused on improving containment of the aircraft’s two existing lithium-ion batteries and adding more temperature monitors to provide earlier warning of abnormal battery performance via the engine indicating and crew alerting system.
Program insiders say that initial data from the tests have reinforced the company’s confidence in its baseline redesign package and that it “feels good” about the revised configuration.
Boeing test captains Mike Bryan and Randy Neville, together with a crew of 11 flight test personnel, completed a second battery monitoring test flight on Feb. 11 on board 787 test aircraft ZA005.
The uneventful 1 hr. 29 min. flight followed an initial flight on Feb. 9, which lasted 2 hr. 19 min. The flights assessed the performance of the main and APU batteries over a matrix of altitudes and speeds. Further ground tests of batteries were conducted on ZA005 on Feb. 13 and the previous day on units in an aircraft destined for LOT Polish Airlines.
However, in addition to the technical challenge is whether the short term, containment-based option being studied by Boeing will be approved by the FAA.
Specifically, Boeing must comply with the agency’s Jan. 16 edict that “operators of U.S.-registered, Boeing 787 aircraft must demonstrate to the Federal Aviation Administration that these batteries are safe.” With the spotlight firmly on the FAA and Administrator Michael Huerta’s promise to “restore the highest level of safety and create the best methods and best procedures,” Boeing is preparing for a dialogue that could be as much political as technical.
Adding to the intensity are questions concerning the FAA’s original certification of the battery publicly posed Feb. 7 by NTSB Chairman Deborah Hersman. Together with its ongoing investigation into the cause of the first battery fire Jan. 7 on a Japan Airlines aircraft at Boston Logan International Airport, the NTSB is evaluating the validation methods originally used for certification of the battery, as well as testing of field replacement batteries.