Twin Towers

[slimjim]

Do you think Osama knew that the towers would collapse or was this a 'bonus' as far as he was concerned? And, if he wanted maximum devastation, why didn't he plan it for later in the day when more people would have been there?

[straz]

I seem to remember video footage of Bin Laden saying he was surprised that the buildings actually collapsed.

[Cactus]

I agree with straz and Tj, i also remember seeing the video footage of him saying he didn't think they'd collapse. (although admittedly, we only have the translator's word for what he actually said). I don't believe he could have planned for the aviation fuel melting the very structure of the building. The twin towers were very strong, and designed to withstand earthquakes and impact from aircraft. I just don't think anyone accounted for the massive amount of heat caused by thousands of gallons of aviation fuel igniting in one hit. I think we give him too much credit for the accuracy of his plan, remember it wasn't an unmittigated success. A further plane was hijacked, destination uncertain, but it was brought down by the passengers and crew before it reached it's target. Hardly a foolproof plan. Having said that, he caused an unacceptable amount of destruction with the parts of his plan that DID work. He's a fanatic, not a mad genius. I really really hope they catch him before he manages to remind us that he's still alive in the worst possible way.

[Obo]

As with the answers above Osama (like he's a personal friend eh!) had no idea they would collapse. The reason they did collapse is because of the unique wat they were built. Instaed of having a ventral service tower housing the lifts and what not which provides most tall buildings with a rigid core the rigidity and strength of the twin towers came from the floors themselves and the exterior of the building. As the aviation fuel burnt (remember both planes where fairly longhaul flights and so were full of fuel) the mountings which held the floors to the exterior of the building melted, the floors began to collapse downward thereby reducing the rigidity of the exterior walls, as more and more floors collapsed the weight of the upperfloors eventually became too great, the walls began to buckle then gave way and the top floors effectively crushed the rest of the building. The reason that the towers were built like that is that to house the number of lifts required for 100+ floors would of meant a huge service tower which was impracticle to build