TryingtoLearn #4154 rightly asks “What went wrong within the engineering process and how can you prove that no other hazards excaped thru the exact same hole in your process.”
787 was first aircraft certificated (partly) under new ''Organisation Designation Authorisation'' (ODA) arrangements, specifically intended to reduce FAA involvement. NTSB Report 2014/AIR1401 tells us what went wrong and how hazardous batteries slipped thru.
“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"
.”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".
"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.”
787 battery fires could easily have cost two planes and all on board. Boeing/FAA Corp. failed to learn. 737 Max is second Boeing certificated under ODA.
Last edited by ozaub; 20th Apr 2019 at 06:28.
Reason: formatting went awry