The Boeing Company

Two lithium-ion battery events in nine days exposed a gap between the safety proposition certified for the Boeing 787 and the behavior of its installed batteries. The first produced fire in a parked Japan Airlines aircraft at Boston; the second forced an All Nippon Airways 787 to divert and evacuate at Takamatsu. Investigators later found that a single-cell internal short could escalate into cell-to-cell thermal runaway, while the initiating defect could remain destroyed or unresolved. The fleet returned through a three-layer redesign that reduced initiation risk, impeded propagation, and contained and vented a failure outside the aircraft. That was an effective operational recovery, but it also changed the accountability question: certification could no longer depend on assuming propagation away; it had to demonstrate that even an unexplained cell failure would not threaten the aircraft.

Boeing 737 MAX MCAS is a risk and accountability case because two fatal crashes, a global grounding, public investigations, criminal-resolution records, regulator return-to-service actions, and continuing safety-governance scrutiny showed how safety-critical automation can shift practical control among manufacturer, regulator, airline, pilot, and passenger. The public record matters because certification evidence is not merely paperwork; it is the proof that design assumptions, human factors, training, delegation, and repair decisions protect people who cannot inspect the automation carrying them.

The opening in the side of Alaska Airlines flight 1282 was the visible failure. The harder accountability question lay behind it: how a safety-critical configuration could be changed on a factory floor without a durable record, restored without the required inspection, accepted behind finished cabin walls, and delivered into passenger service.