Certification lessons learned by the following the battery incidents include the need to involve experts outside of aviation when developing airworthiness standards for new technologies, Peggy Gilligan, the agency’s associate administrator for aviation safety, told a congressional hearing on June 12.
When the special conditions for certification of the 787’s batteries were developed, the FAA “should have gone to experts on lithium-ion batteries” for comments, she told the House of Representatives subcommittee on aviation. “We will do that in the future,” she added.
Other lessons learned relate to’s “multi-tiered supplier dynamic.” While this approach is not new, “the FAA has determined that we need to spend more time overseeing communication and ensuring a clear line of accountability for all required changes down the supplier chain,” she said.
“We will also look for ways to improve the integrity of the [certification] process with the addition of an independent review of the work done,” Gilligan added.
Special conditions for certification of the 787’s lithium-ion batteries were developed following a review of available technical literature on the technology. This resulted in an issue paper and proposed special conditions that were published in April 2007.
The development of special conditions was required because existing certification standards for nickel-cadmium and lead-acid aircraft batteries did not address the issues with lithium-ion batteries, which provide higher energy with less weight but incur a fire risk.
“We developed the standards with industry and put them out for comment,” Gilligan said, but FAA did not actively seek input from lithium-ion battery experts outside aviation. “We need to find a way to reach out to the community of experts not in aviation when introducing new technologies.”
The special conditions for 787 battery certification were published in November 2007. In March 2008, industry standards body RTCA published safety guidelines for use of lithium-ion batteries in aircraft, but the 787 rules were not changed “because Boeing had already supplied data showing strong compliance with the special conditions the FAA had developed, and the new standards did not indicate anything unsafe,” she says.
Gilligan also defended the long-established use of designees to determine manufacturer compliance with certification regulations on behalf of the FAA. In place since 1938, the designee program “is critical to the success and effectiveness of the certification process,” she said.
The FAA review of 787 certification, started in early February after the two battery incidents, is to be completed in the summer, Gilligan said. The review is looking “beyond the battery, at all operational data from the aircraft from entry into service, to see any trends or set of incidents,” she said.
“We have identified a couple of areas and launched deeper dives. We expect the review to produce findings and recommendations for process improvements and other actions.”