In “War ? Part VII” on March 4, Al Duncan asks a number of questions basically aimed at luring readers to the conclusion that the collapse of the World Trade Center (WTC) buildings was some sort of planned event by our government.
Al”s first question is: “Did you know that jet-grade kerosene burns at 1,200?F and that it takes 2,750?F to melt steel? …” However, nobody claims the steel in the WTC melted. Rather than melting, steel fails at roughly 1,000?F. By fails I mean that it loses its ability to support a load. Heated to around 1,000?F, the steel begins to sag and induces tension between the supports (columns) which pulls them together quite forcefully.
As stated in http://en.wikipedia.org/wiki/Collapse_of_the_World_Trade_Center the National Institute for Science and Technology found that sagging floors pulled inward on the perimeter columns and “This led to the inward bowing of the perimeter columns and failure of the south face of WTC No. 1 and the east face of WTC No. 2, initiating the collapse of each of the towers.” This is entirely in agreement with what I learned during my 34- year career as an industrial fire protection engineer.
Al”s next question is: “Did you know that in all of history, a steel building has never collapsed due to fire?” This is false. Two classic examples are the fire in the General Motors Hydra-matic transmission plant in Livonia, Michigan which destroyed the entire plant in about 45 minutes and the spectacular McCormack Place Exhibition Hall fire in Chicago. Numerous smaller examples exist.
Third: “Did you know that both WTC towers collapsed straight down, directly into the path of most resistance ? which would be utterly impossible under the government”s official “pancake” scenario?” Wrong again. Since the collapses began in intermediate floors, the entire weight of the floors above bore down on the floors below, crushing them. This took two seconds longer than free fall. For a scholarly discussion of this see http://www.tms.org/pubs/journals/JOM/0112/Eagar/Eagar-0112.html.
Fourth: “Did you know that three buildings within the WTC came down on Sept. 11?” This is true.
Fifth: “Did you know that Building 7, the third building, was pulled (a demolition term) on Sept. 11, a last-minute decision by the WTC owner?” This is false. Falling debris from the North Tower (WTC No. 1) seriously injured Building 7 and subsequent fires burned long into the day, eventually resulting in collapse of the building. See: http://www.debunk911myths.org/topics/Collapse_of_7_World_Trade_Center.
Bert L. Atwood, P.E. (Retired)
Kelseyville
