The Physical Impossibility of the WTC Collapse explanation
By Eric Harrington
The 9/11 Truth Movement has brought to light many questions about the veracity of the official story of the events of 9/11. The holes, anomalies, and outright contradictions that permeate the official account, while suspicious, are often at the minimum arguable, and numerous people have tried to debunk the literally hundreds of suspicious aspects of the 9/11 story.
It is somewhat surprising to me that one inarguable conflict with the Official story regarding the World Trade Center collapses has never been widely circulated. I say inarguable, because this problem is a matter of pure physics. Not eye witness accounts of molten metal. Not multiple accounts of hearing loud explosions prior to the collapse. Not the unexplainable collapse of WTC7 that was not struck by a plane. There are literally hundreds of these problems with the official story, but none are clear, inarguable products of physical analysis.
Several years ago, while in the throws of 9/11 truth momentum, I identified a thought experiment akin to those which allowed Albert Einstein to recreate our understanding of physics. I was considering the collapse of the WTC towers and the remarkable, near freefall speed with which they collapse and I wondered how much conservation of momentum would affect the collapse speed.
In this thought experiment, I envisioned the 110 floors of WTC towers suspended magically in the air with no support whatsoever. We assume each floor has the same weight X and the distance between floors is consistent and represented by the variable Y.
At some moment the top 17 floors with a mass of 17X (the section above floor 93 in WTC1 that began the collapse, falling as a solid unit) begins to fall as one piece down toward the next floor. This mass of 17X is accelerated at the normal acceleration of gravity or 32 feet per second per second (32ft/s/s) as it falls the 11 or so feet to the next floor. Very straightforward 9th grade physics, but it is at this first impact that it gets interesting.
When the top 17 floors or 17x collide with the next floor, they instantaneously accelerate the next floor to ALMOST the speed they are traveling, but not quite. The next floor has inertia and it takes energy away from the falling mass to accelerate it to the speed of the falling mass. So after the collision, the new mass of floors or 18X instantaneously begins moving down at 17/18ths of the speed the original 17X mass was traveling. The new 18X mass continues to fall till it reaches the next floor and is decelerated to 18/19ths of it’s speed just prior to the collision. This process continues all the way down, each successive collision slowing the falling mass by a increasingly smaller, but precisely calculable amount. Diagram A illustrates this process in more detail.
There is one VERY important thing to keep in mind here. This is not speculation, or guestimation. It is pure physics. But to insure this analysis is conservative lets first consider all the factors that would also contribute to slowing the collapse that are NOT considered here in this calculation:
1) Air Resistance
As the floors fall they compress the air between them which absorbs the energy of gravity pulling the collapsing mass down. This resistance is small but significant and easily calculated IF the falling mass did not disintegrate. But it clearly does in the videos, and so to calculate the air resistance would be incredibly complicated. But it is not insignificant.
2) Support Columns
Of course, the elephant in the room in this scenario is the steel support columns. These columns were designed to support the building though high winds AND the force of gravity, and EVERY SINGLE Column that is shattered in the collapse absorbs energy that is pulling the debris down. Every crushed concrete slab is absorbing energy of the collapse. And the most important thing to remember is, THE ONLY ENERGY AVAILABLE TO PULL THE DEBRIS DOWN IS THE FORCE of gravity. There is nothing else, and it is a finite sum. So every single little resistance SLOWS the collapse. Every Chair that’s crushed, every beam, column, floor pan, EVERYTHING crushed, distorted, shattered, ripped, or torn absorbs energy and SLOWS the collapse.
3) Debris plume.
These calculations assume that ALL the material of the building is retained in the collapsing debris flow. But that was NOT the case in reality. Anyone who watches the video will see a huge plume of dust and debris ejected away from the collapsing building. This ejecta REDUCES the mass of the falling debris flow subsequently increasing the time for collapse even more.
So what does all this mean?
Well the math to actually calculate the time expected for the 17 floors to fall through the lower 93 in this thought experiment is extremely complex and well, beyond my current skills 30 years after graduation from college physics, and far too abstract for this article. But when I originally conceived this thought experiment and set up the problem as described in the Diagram A I began to inquire through the 9/11 truth movement if there were any accomplished mathematicians that might be able to do the heavy lifting of this problem. I was referred to a Math PHD colleague of Steven Jones at Brigham Young University by the name of Professor Kuttler, and when I spoke to him on the phone, I was surprised and flattered to discover that he too had thought of this very same thought experiment and he had actually done the laborious math! Actually, he had used a computer to simplify the very complex calculation.
The result? When calculated considering ONLY conservation of momentum, the estimated time of collapse came to over 14 seconds– 2-3 seconds longer than the time observed on countless videos of 11 seconds which is very close to free fall speed, or the time it would take for a brick to fall from the roof to the ground. And this 2-3 seconds increase is considering ONLY conservation of momentum, and completely ignoring the HUGE resistance and accompanying slowing of the collapse presented by the columns, as well as air resistance etc. etc.. This additional resistance to the collapse should conservatively add many more seconds pushing the collapse duration to well over 20 seconds, if not stopping it all together midway through the collapse. Dr. Kuttler’s prepared a paper on his analysis (a far more detailed and precise than the simple thought experiment explained here) and it can be found at:
But the analysis in this thought experiment is pure math, clean and inarguable, and I challenge ANY physicist to do the work… do the math, and demonstrate purely based on conservation of momentum how the WTC tower #1 could have possibly collapsed in 11, 12 even 13 seconds.
For me, this analysis is conclusive. It is PHYSICALLY IMPOSSIBLE for the WTC towers to collapse in less than 14 seconds, (or really far longer,) and the observed speed of 11 seconds (official NIST report) could only be accomplished though the use of explosives in a well designed demolition.
Who set them, when or why is an open question of which I have no answers. But the FACT that explosives were used, and that they accelerated the buildings collapse (and likely actually caused it) is inarguable from a purely scientific perspective. And once you admit that one problem, the whole official account begins to fall like a house of cards.
Conclusion… Conservation of momentum in the WTC tower collapses ALONE makes the official story impossible. When you then include all the resistance from the THOUSANDS of TONS of STEEL support structure that had to be utterly destroyed for the collapse to persist, the official explanation is proven to be patently absurd, and demands a new and unbiased investigation. I challenge any physicist worth his salt (and not on the government payroll) to debate this conclusion with me.
So I hope we can get to the roots of this tragedy, so something like it never happens again.