Profound Implications of the Observed Downward Acceleration of the North Tower -- Article by David Chandler Published

The editors of the Journal of 9/11 Studies are pleased to announce publication of the following peer-reviewed article in the February 2010 volume of the Journal:

Destruction of the World Trade Center North Tower and Fundamental Physics
By David Chandler

Physicist David Chandler continues his insightful analysis of the destruction of three WTC skyscrapers on 9/11/2001 in this very readable paper. From the summary:

The fact that the roof line of the upper section of the North Tower continued to accelerate downward through the collision with the lower section of the building indicates that the upper section could not have been acting as a pile driver. As long as the roof line was accelerating downward, the upper block exerted a force less than its own static weight on the lower section of the building. Any accretion of material into the upper block would have acted as an inertial brake, reducing the force of interaction even further. The undamaged lower section of the building was built to support several times the weight of the material above it, but whether or not we take the safety factor into account, the reduced force exerted by the falling mass could not have been what caused the violent destruction of the building seen in numerous videos. The persistent acceleration of the top section of the building is strong confirmation that some other source of energy was used to remove the structure below it, allowing the upper block to fall with little resistance.

The editors highly recommend this article and the associated videos by David Chandler.

David Chandler's VIDEOS have moved...

In David's Blog, he gives details.


It's the high school physics paper that ate New York!

Pass the word to every physics class in existence. Great way to capture academic interest too.

What are all those smug PhD's going to say when you ask them about this sort of physics?

"Well.. um.... er... hey, that would be a good one for extra credit."

Nice paper

Thanks to David Chandler for this. I hadn't considered the inertial brake of the accreted matter. It would begin to accelerate downward immediately, upon being accreted (and assuming a best-case scenario wherein it was free to move downward), but the initial velocity would be zero, so it would require time to "get up to speed" with the falling "block."

The counter-intuitive realizations in the paper make for excellent thought problems. This paper is an excellent complement to the "Missing Jolt" paper. Well done.

Accreted material actually would slow the decent!

That is something I have wondered about for a long time and now I have the answer. Thanks David for your hard work and for this excellent paper. Your explaination smashes the last vestiges of credibility for Bizant's pile driver theory. By the way David please contact me if you need video work done I have professional equipment and live close by where you went to school in Clairmont CA. If you still live in So Cal I would be glad to help you put this on video or even work on other presentations. I can be reached at ruffadam2003(AT)yahoo(dot)com. Thanks again David well done.

Congratulations - Another David Chandler Physics Blockbuster

David continues to knock the ball out of the park! Architects and Engineers for 9/11 Truth uses his work routinely to show how the simple and intuitive physics of 9/11can lift the veil of ignorance, sloppy thinking, and denial of the disturbing truths about the destruction of these 3 high-rises.

Richard Gage, AIA, Architect

Please, Richard, tell the rest of the story.....

This is a good analysis and

This is a good analysis and correct as far as I can tell. However the top of the towers above the plane strike zone or below it were not solid blocks and treating it as such is a simplification.

In fact, the buildings were mostly air and a more accurate description would be a rigid square grided tube surrounding a (lattice) of stout steel columns with relatively thin floor slabs of light weight concrete poured in place over pre assembled truss supported corrugated metal decking. The perimeter of the core (24 columns) supported 50% of the floor load and the pre assembled staggered grid of closely spaced columns of the perimeter supported the other 50% of the floor and roof loads. The center of the core carried the antenna and the loads of the floors in core interior... some mechanical equipment and roof loads. The hat truss connected the tube perimeter to the strong core structure acting like a stiffener at the end of the hollow tube.

It's most likely that the free fall acceleration of the top of the top indicates that the entire top section - core and perimeter were being destroyed much the way a building is destroyed at its bottom and gravity causes it to fall at or close to free fall acceleration with nothing to resist its mass. So the top was in the form of a "classic controlled demolition" beginning at about the crash sites.

But the problem for those who planned to destroy these buildings is that the top above the crash site which had broken apart from gravity and explosions would have simply remained a pile of rubble and debris up there at the 80th floor so, perhaps some of it crushing through a few floors below the crash site before it was resisted and came to a stop. ooops

So they did the big show and set off a rather large blast which shot out bits of steel and everything left up there in all directions and created a huge almost mushroom shaped head of a rapidly expanding cloud of dust. But the second part of the show was already underway as lower down in the structure connections to the core were being attacked by thermite and exploded apart so the columns could not support the loads above. Core columns were pushed off their seats, and they came crashing through light weight floors and shaft ways at close to free fall acceleration. All concealed by the perimeter and the dust cloud.

The perimeter of the cores at the girders which surrounded them were blasted outward turning the lightweight concrete slabs into powder as a shock wave pushed against the facade's perimeter columns which had been freed at the corners by incendiaries and explosives. They peeled away and broke into large sections laying out in a cross shaped debris field.

To complete the total destruction a few of the cores were burned away lower down in the structure and they too could no longer support the weakened and extremely damaged remaining central core steel which was like a huge grid like spire. It teetered a bit and collapsed down like a freed stalactite shooting down at free fall acceleration to the earth below.

The south tower almost gave it all away as the upper CD went awry and one side was undermined ahead of schedule and the upper part began to tilt like a tree felled from a woodsman's axe cuts to one side. It should have gone over. And everything would have ended there and the fires up there extinguished with nothing left to burn. So they hastened up act two and blew the tilting top to bits as it was toppling over and then began the same big explosion and downward sequenced destruction.

Debris from the facade panels stretched 600 feet from the towers facade and some fell onto the WFC and ripping through the Deutchebank which faced the west and south facades of the south and north towers. Massive perimeter sections plunged from 1000 feet and right through the adjacent WTC 4, 5 and 6 right into then basement.

No pile drivers at work that day... just flying sections of heavy steel.

simplification OK

Sandero, you are right of course that treating the top section as a solid block is a simplification. It was Bazant's simplification. It is not however a detrimental simplification to the paper. What the paper shows is that, even if you treat the top as a solid block, thus giving it the best chance of damaging the lower section, the building still can not come down in the observed manner.


Frank - can one say that if the upper part had been monolithic, it would have been easier for it to destroy the lower part? Because in that simplification the much bigger lower part is also seen as a monolith.

good point, solid top implies solid bottom

The plain fact is that the lower portion was stronger than the falling upper portion. It was made of thicker steel and had not been fire damaged nor hit by a plane.

It is interesting to follow this line of argument through. Suppose we ignore the video evidence that the top disintegrated first, and just consider the impact of a solid top on a solid bottom. Let us allow that Bazant was right in saying that the first impact would be sufficient to destroy the top floor of the lower section.

Now let us ignore the fact that the top was weaker than the lower section. Whatever damage occurred to the top floor of the lower section would inevitably occur to the lower floor of the top section, as it would experience the same impact. So now we have two floors destroyed, one on each section, and the top continues to fall, 12 storeys now.

Let us now also ignore the consumption of energy and loss of momentum. The falling top would hit the next floor and destroy it, and the impact would destroy another floor in the top. It is now 11 storeys.

Let us now also ignore the fact that the top block is getting smaller and assume it can still hit with the same impact.

You can see where this is going to lead. After 13 impacts there will be no top block and the bottom section will 13 storeys shorter. What will happen then? Nothing. 84 storeys will remain.

It seems no matter how much leeway you give the official explanation, it just doesn't result in total collapse at any speed.

point of no return..

Thank you Dr. Jones for this post. I linked to your blog and article from Flyby News. It surely seems like we are at a point of no return. Either we successfully reclaim science and justice, or our civilization will go down at near free fall speed.

Articles like this give hope for surviving through the tremors of deceit and betrayal.

<>~<> <>~<>
for life's survival in the 21st Century

Issac Newton came to me and said ---

"David Chandler is da man."

That's the stuff David!

That is what we've been needing to see. You can now build upon that paper, with any number of proofs and their accompanying thought experiments. This whole issue is easily solved by grade 10,11 level physics students, who will follow your lead and prove it well beyond any reasonable doubt, time and time again, from generation to generation, armed with nothing but a few videos, a stopwatch, and some basic equations including Gallileo's Law of Free Falling Bodies and Sir Isaac Newton's Three Laws of Motion.

Keep going with this - now it get's interesting, when UNDEBUNKABLE scientific proofs such as this start surfacing, because soon, a whole new generation of people will come to recognize the 9/11 official story myth for what it is, and represents in history, and that is when the 9/11 event may begin to SERVE a cause of truth and justice worthy of the victims, and the many victims created in their name, and worthy of us all and the very cause of truth and justice, and freedom, as the great point of historical leaning that it is, and will remain - since those twin towers shall remain forever conspiciously absent the New York City Skyline. It can never be forgotten and future generations they need to KNOW that everything they were told about it, is a LIE, a very Big Lie of the very worst kind, and one which almost brought the USA to it's knees at the outset of the 21st century. Surely, thanks in no small part to the work of people like you, and me and everyone, history will get this story staightened out to a very large degree, such that the Zelikow narrative (public myth) will be flat out rejected as a valid historical frame of reference.

Thank you, so much, for being a causal agent of change. Good work!
On the 11th day, of every month.