Creative Speculation

David Chandler measured the position of the tower roofline in a video at 5-frame intervals. He then drew a straight line through the points and declared that the straight line meant that the top section was "uniformly" accelerating. That is his first invalid inference, and one that shouldn't be expected from a scientist: It only meant that within the limits of his measuring technique, on average, the acceleration was fairly uniform. Measurements taken on a much finer scale could easily show waves of fluctuations instead of Chandler's straight line.

Chandler then uses that (invalid) "uniform acceleration" premise to infer that the structure must have been exerting a reaction force of only about a third of the weight of the top section. But, Chandler declares, that's only 1/9th of what the structure was designed to carry (i.e. three times the weight), so "something" must have removed 8/9ths of the columns, very rapidly, and that could only be magical silent explosives.

That conclusion is abject nonsense on its face, even if real-world KABOOM-type explosives were used: Removing 8/9ths of the columns would not produce a uniform acceleration! I defy Chandler or Gage's other "experts" to propose any realistic failure modes that would produce a uniform acceleration, but blowing out columns certainly would not.

What would happen is that the remaining columns would quickly buckle. When a column buckles, its carrying capacity drops drastically, down to virtual nothing if it folds in half, or exactly nothing if it breaks before it bends that far. For a 12-foot column, buckling would begin after only a few inches of downward deflection. After that point, the column would no longer be able to provide the three-times-design-load reaction force Chandler assumes (which isn't quite accurate, but it doesn't matter). And as the reaction force diminished, the falling mass above would see an increase in acceleration, up to and including one full g before impacting the next floor.

But even worse for Chandlers nonsensical conclusion is that column buckling was not the primary failure mode in the WTC towers. Instead, floor joists and beams were mostly ripped from their connections before columns buckled, leaving unbraced columns to buckle or be pushed aside later. The connections sheared after decelerating the falling mass for only a fraction of an inch, after which the debris would go into free-fall until it hit the next floor.

So, even if magical silent explosives had been used, the collapse would have been thousands of individual failure events, with thousands of different clumps of debris alternately decelerating when they hit a floor and then accelerating again when that part of the structure gave way. All you could hope to measure at the roof, with the top riding down on a cushion of debris and individual failure events spread out over time, would be an average of all those events, and an average acceleration of debris that was actually undergoing wide fluctuations in acceleration, up to and including free-fall.

And the point is, the same thing would happen with a purely gravity-driven collapse, with failures caused by the dynamic impact loads, which Chandler completely ignores with his "uniform acceleration" nonsense. No magical silent explosives required. Several people (e.g. Dr. Greening) have done the type of dynamic analyses that Chandler doesn't even attempt and come up with collapse rates that match well with the observed rates, so there's really no mystery that needs to be solved with magical silent explosives.

There is no reason to think that Chandler's point measurements actually imply uniform acceleration, and since there is no realistic way to get a uniform reaction force from failing structural components, there is no logical reason to expect uniform acceleration, even with 8/9ths of the columns blown away. And without uniform acceleration, the rest of the Chandler/Cole argument is worthless. It may pass for "science" in Trutherville, but the only thing that Chandler and Cole prove is that being able to state Newton's laws and being able to apply them intelligently in the real world are two different things.