NTSB has just published its report on Boston battery fire. It's at
http://www.ntsb.gov/doclib/reports/2014/AIR1401.pdf . Have not finished studying it yet but conclusions (below) point to disturbing corner cutting by Boeing and FAA:
7. Boeing’s electrical power system safety assessment did not consider the most severe effects of a cell internal short circuit and include requirements to mitigate related risks, and the review of the assessment by Boeing authorized representatives and Federal Aviation Administration certification engineers did not reveal this deficiency.
8. Boeing failed to incorporate design requirements in the 787 main and auxiliary power unit battery specification control drawing to mitigate the most severe effects of a cell internal short circuit, and the Federal Aviation Administration failed to uncover this design vulnerability as part of its review and approval of Boeing’s electrical power system certification plan and proposed methods of compliance.
9. Unclear traceability among the individual special conditions, safety assessment assumptions and rationale, requirements, and proposed methods of compliance for the 787 main and auxiliary power unit battery likely contributed to the Federal Aviation Administration’s failure to identify the need for a thermal runaway certification test.
None of which will surprise those who have followed the sorry saga or read earlier JTSB report at
http://www.mlit.go.jp/jtsb/eng-air_report/JA804A.pdf.