What was the free-fall time for the top part of the WTC?
Assuming the top bit of WTC-1 weighed one-fifth of the total weight of the tower, or 100,000,000 pounds, and that the cross-sectional area in the direction of travel was 43264 sq ft (208 squared), that the drag coefficient was 0.7, and that the height of fall was 1,368 feet, we come up with a terminal velocity of 158 ft/second.
(Calculator is here;
http://exploration.grc.nasa.gov/education/rocket/termvr.html )
Calculating the free-fall time with that terminal velocity we get a free fall time of 11 seconds.
The standard estimate of the time of the tower to fall is 15 seconds. I haven't (yet) measured it myself, but 15 seconds is NOWHERE near 11 seconds. Not even CLOSE to 11 seconds. In fact it is 36% more.
So, I've just shot down the free fall argument.
And if you are gonna argue against it, you'd better find fault with that calculation. Anything else is the desperate attempt of a true believer resorting to the Gospel According To Jones.
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