Source:
http://tangibleinfo.blogspot.com/2008/08/wtc7-collapse-incredible-conclusive.html
Debunking NIST's conclusions about WTC 7 is as easy as shooting fish in a barrel.
Symmetrical Collapse
NIST lamely
tried to explain the symmetrically collapse as follows:
WTC 7’s collapse, viewed from the exterior (most videos were taken from the north), did appear to fall almost uniformly as a single unit. This occurred because the interior failures that took place did not cause the exterior framing to fail until the final stages of the building collapse. The interior floor framing and columns collapsed downward and pulled away from the exterior frame. There were clues that internal damage was taking place, prior to the downward movement of the exterior frame, such as when the east penthouse fell downward into the building and windows broke out on the north face at the ends of the building core. The symmetric appearance of the downward fall of the WTC 7 was primarily due to the greater stiffness and strength of its exterior frame relative to the interior framing.
NIST can't have it both ways. If the exterior frame was so stiff and strong, then it should have stopped the collapse, or - at the very least - we would have seen a bowing effect where tremendous opposing forces were battling each other for dominance in determining the direction of the fall.
In real life, the thick structural beams and "stiff [and strong]" exterior frame used in the building should have quickly stopped any partial collapse, unless the support columns were all blown. At the very worst, we should see a 1 or 2 floor partial collapse.
Freefall Speed
NIST said that WTC 7 fell at 40% slower than freefall speed. But it collapsed
alot faster than it would have if the structural supports were not all blown away at the same instant. 40% slower isn't very impressive -- that's like arguing that a rock falling through concrete 40% slower than a rock falling through the air is perfectly normal.
Again, why did the building collapse at all, given that the thick structural beams should have quickly stopped any partial collapse?
911 wtc 7 new angle
Bomberne der forsvandt 06