"Bjørnar Bolsøy" wrote in message
...
Alan Minyard wrote in


Looking at the video of the south tower impact, doesn't the huge
fireball outside the building seem to suggest that much, if not
most, of the fuel burned up on the outside?


The fuel on the aircraft perhaps but the trouble is there was large
fuel load in the building in the form of furniture, carpets, paper
computers etc. The fireball ignited all of that fuel simultaneously
and the impact destroyed fireproof partitions and knocked
the fireprrofing off the floor struts. It was the heat from the subsequent
fire that cause those struts to fail. Once they had done so the bracing
between the outer wall and inner core that was essential to the
strength of the building was lost and outer skin failed in buckling.
The damager inner core was unable to tale the extra stress and also
failed.

This sequence can be clearly seen in the video footage.

Keith