Friday, September 5, 2008
Here is a video of the demolition of the Landmark Tower, Fort Worth, Texas:
The Landmark Tower was 380 feet high.
According to the timer on Youtube, it took about 7 seconds from the start of the collapse (once the building started to fall) until the last of the building reached the ground.
Or check it yourself: here is an online stopwatch (click the green arrow on the left).
WTC 7 was 576 feet high (counting the rooftop penthouses, it was 610 feet; but since the penthouses collapsed a couple of seconds before the main building, and was thus part of a different and discrete process from the collapse of the main building, and - most importantly - because the collapse of the penthouse is irrelevant to the question of whether the main building itself fell as fast as known demolitions, we will ignore the penthouses for now).
WTC 7 collapsed in approximately 7 seconds, not counting the earlier collapse of the penthouses. See this video, and other videos here.
So how did a 576-foot building collapse in the same time as a 380-foot building? Even using controlled demo, that would be an impressive feat.
But let's bend over backwards to be reasonable. Let's add a full second to WTC 7's apparent collapse time - let's call it 8 seconds - to be make sure we are not underestimating how long it took building 7 to collapse.
How did a 576-foot building collapse in 8 seconds when a 380-foot building took 7 seconds?
Acceleration would not have caused the additional 196 feet of Building 7 to disappear in the last second.
Bottom line: WTC 7 collapsed at the same speed as known controlled demolitions.
I encourage researchers to compare the collapse times of other demolitions, and then let me know what you find. Other videos of known controlled demolitions can be found here, here and here.
Hat tip to Dr. Steven Jones. By way of background, I asked Dr. Jones how to calculate collapse speeds in air, to compare with WTC 7's actual collapse time. Dr. Jones responded collapse times in air depends on many variables and is very difficult to calculate, and so it would be better to compare WTC 7 collapse time with known controlled demolition collapse times.