Diane over at NYC Activist continues to impress me with her well-reasoned posts. Check out this one on why the Troofers shouldn't hang their hats on controlled demolition.
For an example of what I mean by overstating the case, a lot of folks have claimed that the sheer speed of collapse inherently violates Newton’s laws.
In fact, the towers did not fall with exactly free-fall acceleration. They fell a little bit slower than that.
The question is whether they fell slower enough to be consistent with an alleged purely “natural” collapse. That’s a quantitative question, not one that can be answered with simple hand-waving.
Zdnenek Bazant and other defenders of the official story have claimed that, once the collapse of either of the Twin Towers got going, the resistance of the columns to being shattered was “negligible” compared to the impact of the top part of the building falling on top of them.
If indeed this claim is true, then what should be the expected collapse time? Using my own oversimplified computer model for WTC 1, assuming a top-down collapse starting at the 95th floor, with totally inelastic collisions and no matter being ejected out of the building, I got 10.5 seconds for the time of descent of the collapse front. Adjusting my model to eject about 70% of the mass of each floor outside the building (probably an unrealistically high estimate), I was able to increase the fall time only to 12 seconds.
So, it seems to me that we can’t prove demolition based on collapse times alone. Based on my own calculations, the fall time might be consistent with the official story, if indeed it’s possible that the resistance of the columns to being shattered could be “negligible” compared to the impact of the top part of the building falling on top of them. Is the latter claim plausible? That too is a quantitative question. It can be answered only by people with an in-depth familiarity with the properties of steel, including how steel deforms.
And she goes on to admit that's not an area in which she has expertise.
Now that strikes me as a truth-seeker. The post is not perfect (she apparently does not know about the photos of WTC 7 which clearly show the building collapsed slightly to the south, not symmetrically by any means). But she's serious about learning, as we can see from here:
For more about this issue, see the September 11 archives page on the Progressive Review site, including a synopsis of a 1976 book by New York City Fire Commissioner John O’Hagan, High Rise Fire and Life Safety, in which O’Hagan worried about the possibility of the Twin Towers collapsing due to fire.
Whether or not these worries were in fact justified on the grounds given, it would seem that the hypothetical possibility of a steel high-rise building collapsing was not totally unheard of among fire fighters or among fire safety experts before 2001.
It will be instructive to see how the "Truth" movement reacts to someone like Diane. Those who are sincerely interested in uncovering what happened that day will embrace her honesty and diligence because if there really is something to be uncovered, (something I admittedly doubt strongly) it will be folks like her who will uncover it. And those who are interested in selling DVDs and books and holding conferences will undoubtedly attack her for failing to toe the "Controlled Demolition is Truth inviolate" line.
Labels: Controlled Demolition