I believe that plane was carrying lithium-ion batteries as cargo - something it would be illegal to do in the US on a passenger flight. A fire makes the most sense to me. Some investigator put together a fire scenario that explained all the observed happenings. I read it over two years ago but I don't remember the source.
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
Albert Einstein
Albert Einstein