I watched a show on the Towers, and according to one of the designers, the building was designed to withstand a impact from a airplane, BUT they did not factor in the heat from the explosion, it was the heat, that added to the death blow for the buildings, the heat added to the stress on the structure, softing the steel.
Now no flames please, I watched the show on the history channel, or the discoery channel, it has been on several times.
In one of the interviews, the buildings designer said that when they designed the buildings, the line of thought was a lost plane, in dense fog, and impact with one of the buildings.
No matter if the buildings could have stood, or not, the fact that they stood as long as they did, I believe added to the list of people who survived the area. For that I am very gratefull.
I also think it is damn shitty for someone to sue the desiners of the Towers, why the hell dont they sue the damn terrorist who commited the act?