Looking Beyond Single Incident To Underlying Process
The NTSB on Tuesday opened two days of hearings focusing on the battery fire that occurred aboard a Boeing Dreamliner in January, and to hear from representatives of the FAA, The Boeing Company, GS-Yuasa and Thales about the design, testing, certification and operation of the lithium-ion battery on the Boeing 787 and the battery fire incident.
"We are looking for lessons learned, not just for the design and certification of the failed battery, but for knowledge that can be applied to emerging technologies," NTSB Chairman Deborah Hersman said in opening the hearing.
Reuters reports that Hersman occasionally had to act as a referee between those asking questions and the witnesses, at one point telling Boeing executives that they should be cautious about giving vague answers to the questions.
But both the FAA and Boeing stood behind the certification decision made while the Dreamliner was being designed and built. Mike Sinnett, Boeing's chief 787 engineer, said that because there was not a larger "catastrophe" aboard the airplane on which the battery caught fire, the process was validated.
He did say that the incident showed that the planemaker should go further in challenging test assumptions, and that the company should "seek to understand the test criteria a little bit more."
Ali Bahrami, the transport airplane manager for the FAA agreed that the agency needs to "dig deeper to find out what (an incident) is telling us, so that we can absorb that information and roll it into future designs," adding that the FAA did not conduct its own tests, but relied on Boeing and its contractors to complete testing and analysis. The FAA is "an independent set of eyes," Bahrami said.
The batteries failed at about 60,000 hours of fleet flight time, rather than the one-in-one-million flight hours odds predicted by the testing.
A new standard established by the RTCA (Radio Technical Commission for Aeronautics) for lithium-ion batteries was released five months after the battery systems were certified by the FAA. When asked why the systems were not re-tested to the new standard, FAA manager Steve Boyd said that "in some cases (the RCTA standards are) more severe than they needed to be."
At a news conference following the hearing, Hersman said the testing that was conducted "really didn't replicate the worst-case conditions that we saw in the events of January."
(NTSB Images)