ericmurphy
Posts: 2460
Joined: Oct. 2005
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As I said before, I'm not discussing (or at this point interested in) whether there is some conspiracy involving the government (and as I said, the official story is nothing if not a conspiracy theory). I'm interested in discovering if the official story is plausible, or even possible.
| Quote | | Here's how I understand it: The force that actually brought the towers down was gravity pulling straight down. The collapses started when just one or two of the few damaged floors gave way, basically all at once. It's impossible to say the exact sequence of events, but once one side of one floor gave out, the other sides of that floor couldn't hold. (If the side opposite the initial collapse was very very strong, it might have supported the structure long enough for it to start to topple over into the collapsed "notch"' like the felling of a tree) |
Actually, I've watched the video of the collapse of WTC 2 (the south tower) at least a dozen times. In that video, it is clear that the upper 30 stories of the tower actually do start to "topple" (i.e., do not fall straight down) to the south side of the tower. Obviously, the top 30 stories of the tower should be more or less structurally intact; certainly no floor above the 85th floor suffered any structural damage. In the first few seconds of the collapse, this large, 30-story tall structure rotates about 7 degrees as a unit. About five seconds into the collapse, however, this entire structure, weighing several tens of thousands of tons (and which should have reached the ground more or less intact) completely disintegrates losing all its angular momentum, and collapses into the lower portion of the tower. What caused this catastrophic and virtually instantaneous disintegration of an object the size of a large 30-story office building?
| Quote | | The buildings were designed as a light tubular structures, with much of their strength in their outside edges. |
This is incorrect. The major weight-bearing structures in WTC 1 and 2 were the immense core girders visible in the photos on this page. 47 box girders, 50 inches thick at their bases tapered to about 18 inches at their tops, were capable of supporting the entire weight of the building unaided. In the photo of the debris, none of these core girders shows any sign of deformation. They are all neatly snipped into 20-40 foot sections. In the video of the onset of collapse of the north tower, it is evident that the core structures, which may not have been damaged at all in the collision, failed before the perimeter columns.
WTC 1 and 2 each collapsed all the way to the ground in ~15 seconds. The free-fall time from 1,300 feet (the height of the towers) in a vacuum is ~9.5 seconds. Yet the towers fell through themselves, taking the path of most resistance. 500,000 tons of steel and concrete presented slightly more resistance to the falling debris than air would have.
The floors of the WTC towers consisted of lightweight concrete poured into steel pans, approximately 300,000 cubic yards' worth. All that concrete was converted into ~60-micron powder. There is insufficient gravitational potential energy in either tower to both cause the complete collapse of the towers and convert the entire non-ferrous contents of the tower to dust the consistency of talcum powder.
Each floor of the towers was approximately an acre in area. The floor pans surrounding the core structures was approximately half that area, meaning each tower had approximately 50 acres of steel floor pan topped with concrete. The concrete ended up spread over most of lower Manhattan and parts of Brooklyn, but I was unable to locate any evidence of the floor pans themselves in any of the photographs of of the debris. What happened to the floor pans?
| Quote | | A military aircraft not on high alert status can't just have a pilot jump in then take off. Lots of preperation (fuelling/armament/checks) need to be done before launch. |
But as I noted, more than 60 flights had been intercepted in the 18 months before 9-11. Despite the fact that hijacked aircraft had been in the air for more than an hour, not one of them had been intercepted, even though some interceptors were already in the air at the time Flight 11 was hijacked. Further, none of the aircraft that were (belatedly) scrambled flew at more than a minimal fraction of their top speed (e.g., 400 MPH vice 1,500 MPH). At a bare minimum, the inability to intercept even one of the hijacked aircraft points towards inexplicable incompetence at every level of government, and after all, NORAD has no other mission than to protect American airspace from exactly this sort of attack.
| Quote | | When terrorists fly huge planes at huge buildings they usually miss (and presumably give up on the idea?) |
As for the attack on the Pentagon, the maneuver taken by flight 77 was so extreme that military pilots questioned whether a human pilot could have executed it successfully.
| Quote | | When tall buildings fall down, they are supposed to 'topple over' like huge trees. |
How likely does it seem that very asymmetrical damage could cause perfectly symmetrical collapse? Given the vastly larger number of asymmetrical failure modes, it seems unlikely unless it was planned that way. Did the hijackers plan for a perfectly symmetrical collapse, doing as little damage to surrounding buildings as possible?
In any event, it seems to me that indisputably the single most significant political event of the century deserves something more than the cursory investigation it’s been given so far. Before you dismiss me as the victim of crankery, I think you should review some of the material I cited above, cited here. Surely it’s worth your time. After all, don’t you want to know what happened on September 11, 2001? Surely the topic is not without its fascination.
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2006 MVD award for most dogged defense of scientific sanity
"Atheism is a religion the same way NOT collecting stamps is a hobby." —Scott Adams
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