Was Prof. Chris Wise a scoundrel?
Was Jon Magnusson insane when talking about the insulation?

On Tuesday, the 110-floor twin towers collapsed on to a relatively small footprint, said John MacArthur of Arup consulting engineers in London. "Thank God they came down on top, rather than tilted over. Obviously it was catastrophic but it could have been worse if they went sideways." Designed by the late architect Minoru Yamasaki and Emery Roth and Sons, the facades of each tower formed, in effect, a tube consisting of a lattice of prefabricated steel that supported each floor but was mostly designed to absorb wind forces, providing increasing support towards the base of the building. Central steel columns also took the gravity loads of each floor. A network of steel trusses ran between the two sets of columns, holding up each concrete floor, and a set of plates ran among the trusses to dampen the stress. The towers could deal with ordinary fires, minor earthquakes and hurricanes but not the world's worst terrorist attack. They were rocked first by the impact of each plane, then explosions and finally intense jet fuel blazes. Each plane was on a cross-continental route and would have been carrying heavy fuel loads. The impacts were relatively high up on the towers, stymieing firemen's ability to contain the ensuing blaze. Because the steel tube design is weaker at higher floors, greater damage would have resulted than at the sturdier ground levels. However, Prof Chris Wise of Imperial College said that the impact forces were no more than 20 per cent of the wind forces the towers could handle, so without the fires it is unlikely that the towers would have collapsed. "The most amazing thing is that the buildings stood up at all. Because the buildings did not collapse for at least an hour after impact, there is a fighting chance that maybe half the people got out." Had they collapsed immediately, which probably would have happened without this external steel skeleton, the death toll would have been higher, he said. However, the towers were eventually felled when temperatures reached around 1,000C in the heart of the buildings. The skyscrapers had fire defences, said Jon Magnusson, chairman of Skilling Ward Magnusson Barkshire in Seattle, a firm that worked on the original design. But layers of insulation sprayed on to the steel beams could have been breached by the initial crash and the sprinkler systems may have been disabled or useless in the heat of the jet fuel fire. Prof Wise, who designed the tallest building in Europe, Commerzbank's headquarters in Frankfurt, said that temperatures were highest in the core of the towers, where interior steel columns failed first. They buckled and the collapse of the top of the building overloaded floors below, causing a progressive floor-by-floor collapse. Although it could not prevent the collapse, the steel tube design did contain it.
On Tuesday, the 110-floor twin towers collapsed on to a relatively small footprint, said John MacArthur of Arup consulting engineers in London. "Thank God they came down on top, rather than tilted over. Obviously it was catastrophic but it could have been worse if they went sideways." Designed by the late architect Minoru Yamasaki and Emery Roth and Sons, the facades of each tower formed, in effect, a tube consisting of a lattice of prefabricated steel that supported each floor but was mostly designed to absorb wind forces, providing increasing support towards the base of the building. Central steel columns also took the gravity loads of each floor. A network of steel trusses ran between the two sets of columns, holding up each concrete floor, and a set of plates ran among the trusses to dampen the stress. The towers could deal with ordinary fires, minor earthquakes and hurricanes but not the world's worst terrorist attack. They were rocked first by the impact of each plane, then explosions and finally intense jet fuel blazes. Each plane was on a cross-continental route and would have been carrying heavy fuel loads. The impacts were relatively high up on the towers, stymieing firemen's ability to contain the ensuing blaze. Because the steel tube design is weaker at higher floors, greater damage would have resulted than at the sturdier ground levels. However, Prof Chris Wise of Imperial College said that the impact forces were no more than 20 per cent of the wind forces the towers could handle, so without the fires it is unlikely that the towers would have collapsed. "The most amazing thing is that the buildings stood up at all. Because the buildings did not collapse for at least an hour after impact, there is a fighting chance that maybe half the people got out." Had they collapsed immediately, which probably would have happened without this external steel skeleton, the death toll would have been higher, he said. However, the towers were eventually felled when temperatures reached around 1,000C in the heart of the buildings. The skyscrapers had fire defences, said Jon Magnusson, chairman of Skilling Ward Magnusson Barkshire in Seattle, a firm that worked on the original design. But layers of insulation sprayed on to the steel beams could have been breached by the initial crash and the sprinkler systems may have been disabled or useless in the heat of the jet fuel fire. Prof Wise, who designed the tallest building in Europe, Commerzbank's headquarters in Frankfurt, said that temperatures were highest in the core of the towers, where interior steel columns failed first. They buckled and the collapse of the top of the building overloaded floors below, causing a progressive floor-by-floor collapse. Although it could not prevent the collapse, the steel tube design did contain it.(footnote: http://www.greatdreams.com/trade_day2.htm, also http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2001/09/13/wtower13.xml)