But seriously, fires on aircraft are not always so considerate as to leave vital systems alone? Or to politely put themselves out?
Can't comment on aircraft engines, but for interiors there are flammability requirements and essentially yes, stuff are not allowed to burn or emmit toxic substantances and thick smoke.
Not my area of expertise but there are various tests that consider all possible scenarios including how hot something can get and whether it will affect something else, although that specific item might be okay.



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