I think the physics of skyscrapers makes collapse IMPOSSIBLE.krammer wrote:If Fintan's theory that the angle of attack by the planes was the key factor in triggering the pancake collapse of the twin towers is correct, then it follows that building seven probably did collapse due to structural damage. The lack of cutter charge sounds in any of the broadcast audio or video precludes controlled demolition in my opinion. Although WTC 7 sure looks like a controlled demolition, pre-wiring an occupied office building with explosives does not seem to be a workable theory.
My Python program that runs only on the conservation of momentum with no physical supports takes 12 seconds to collapse. That is with the top mass hitting the lower masses and starting them falling. On various sites I have seen estimates of 8 and 10 seconds for the collapse time of the north tower. Dr. Sunder of the NIST says 11 seconds.
A skyscraper has to hold itself up. To get a collapse time of less than 12 seconds means NO RESISTANCE. Resistance should have definitely meant more than 18 seconds which would be 50% of free fall acceleration.
9/11 is the Piltdown Man incident of the 21st century.
It is an embarrassment to all of the people who claim to understand physics. It is somewhat curious all of the people who claim to know physics and talk about the collapse and then say nothing about the REALLY INTERESTING fact of the speed of that collapse. I would think anyone with SCIENTIFIC curiosity would be all over it. At least that is how scientists were portrayed when I was a kid.
Now they are more pompous and AUTHORITATIVE.