Originally Posted by Firemansam

Apologies I didn't go into my analogy further..
Of course that can be the case for building fires, some roof's are built to last so to speak, but an airplane skin is not built for that kind of heat, and with such small windows on a plane that heat can't be dissipated, therefore a lot of the heat builds in the roof of the airplane and burns through the skin with relative ease, with enough time and heat it would eventually burn the skin towards the underbelly of the plane.