Prelude 9/11 morning Flight 11 hijacked Flight 175 hijacked WTC 1 hit Flight 77 hijacked WTC 2 hit Flight 93 hijacked Pentagon hit WTC 2 collapses Flight 93 crashes WTC 1 collapses WTC 7 collapses Epilogue


Collapse at near-freefall speed, symmetrical, right down through the building’s resistance0


It is unclear if the claim is about the World Trade Center 1, 2 or 7 but in this article, it will be treated as if it covers all three buildings. The claim suggests that freefall speed and symmetry should be signs of controlled demolition, as well as the buildings should have been able to withstand the collapse of some floors due to fire. Since each building collapsed completely, it must mean that they were all destroyed by controlled demolition.


World Trade Center 1 and 2
The World Trade Center 1 and 2 both start their collapses precisely in the area where the planes hit and the sides where the planes caused the greatest damage and where the fires were likewise the most fierce.

The collapses start clearly asymmetrical, by floors on the side where the planes hit breaking down, whereafter the rest of the floors also break down. The top is pulled down exclusively by gravity which is why the top falls down through the building itself.

None of the collapses happen in freefall, which is most clearly observed by elements from the building’s facade, breaking off during the collapse, falling quicker (in freefall) than the collapse itself which lasts considerably longer. A detailed explanation of the progress of the collapses can be found in NIST’s reports1.

The part of the buildings that are below the impacts of the planes does not have a combined own resistance that can withstand a collapse from above. It does not take more than the collapse of one floor, before there is enough energy and mass above to break through all the floors below. Even if the floors themselves were only a few meters high, the energy released is enormous when the many tons from the upper part of the buildings fall just a few meters. The floors were not designed to be able to withstand such force2.

There are none of the most obvious signs of controlled demolitions with regards to the World Trade Center 1 and 2: No rhythmical booms from explosions, no flashes from explosions, and no clouds from explosions either. All three are very clear signs at real controlled demolitions. Neither NIST, FEMA, or other recognized experts have investigated if there could have been explosives in the World Trade Center 1 and 2, but NIST has done this in their investigation of the World Trade Center 73. One can reasonably apply the same conclusion to the World Trade Center 1 and 2, namely that it would be quite implausible, especially since every boom would be about 130 dB which would have been heard over lower Manhattan.

World Trade Center 7
The building is 186 meters tall and takes at least 13.5 seconds to collapse, which combined is way from freefall. During the collapse, a part of the building collapse in freefall for 2.25 seconds, which – for that part – is equivalent to 32 meters. Gravity does pull the building straight down (what else should gravity do?) but towards the end of the visible collapse, it can be observed that the building topples and falls apart.

The visible part of the collapse takes about 13.5 seconds before the area is covered in smoke and dust. Prior to the 13.5 seconds, there are an additional 3 seconds or thereabout where no movement of the building is detectable but where smoke and dust are pressed out of the bottom of the building, indicating that the building has already started to collapse from the inside4.

The collapse was not in freefall, it was not symmetrical, and the building debris spread over the nearby streets5.

It is difficult to get the last part of the claim, “…right down through the building’s resistance” to fit with the World Trade Center 7, since the collapse here does not look like the collapses of the World Trade Center 1 and 2 where the top parts of the buildings plow through the underlying floors. Regarding the World Trade Center 7, the furthest one can go is to consider the eastern penthouse which collapses early as something that falls “right down through the building’s resistance”, since the penthouse is clearly seen falling down through the building itself, partly because it disappears and partly because windows can be seen to be broken on the north side in a straight line down through the building where the penthouse seems to be falling. This is visually very detailed in this analysis6:

It is clear that the collapse is initiated by the fires on the 12th and 13th floors causing column 79 to buckle which starts a progressive collapse of the whole building where the penthouse is merely one of the first visible signs from the outside of the north side. Everything is in accordance with NIST’s investigation of the collapse1.

The penthouse itself does not fall symmetrical: The eastern part falls first, and it does not happen at freefall speed.

There are none of the most obvious signs of controlled demolition of the World Trade Center 7: No rhythmical explosion booms and no explosion flashes of light. Both are very obvious at controlled demolitions. NIST did in fact investigate the possibility of explosives but concluded that it would have been quite implausible. One reason given is that each explosion boom would be between 130 dB and 140 dB which must have been audible on lower Manhatten7.

Freefall speed and symmetry are not necessarily signs of controlled demolition. There are lots of examples of controlled demolitions that are neither freefall or symmetrical8.

130 dB is so loud that the pain threshold for most people is reached. We are thus not talking about booms that cannot be ignored but booms so loud they that would cause most people to feel pain and far exceed the risk of hearing damage9. None of these devastating booms are recorded by a single video camera for miles around, or by witnesses in the area.


The claim is manipulative and misleading because it tries to draw a conclusion based on false premises that freefall speed and symmetry are evidence of controlled demolitions and that there should be resistance enough in the buildings’ nether parts to resist the collapsing upper parts.

The word “near” is so open to interpretation that it can mean anything. It is used to explain away the uncomfortable fact that none of the three buildings collapse in freefall. “Near” indicate that the collapse speed is so close to freefall speed that there must be another explanation than the official one. The claim thus points only to one other explanation, namely that the buildings must have been destroyed by controlled demolition.

Apart from the fact that the premises are false, the claim is also self-contradicting, if it is intended to cover all three building collapses. The three buildings all collapsed differently.

The World Trade Center 2 was hit askew which resulted in the top part tipping far more than the top of the World Trade Center 1:

World Trade Center 1

World Trade Center 2

Compared to the World Trade Center 7, the collapses of the World Trade Center 1 and 2 began where the planes hit, relatively high up, where the top of each building fell down through the nether parts of the buildings.

The World Trade Center 7 was not hit by a plane but was damaged by fires spread over most of the building. After seven hours, the building started to collapse far more progressively, from the inside out, starting on the east side:

World Trade Center 7

In other words:

  • The World Trade Center 1’s “symmetry” does not look like The World Trade Center 2’s “symmetry”
  • The World Trade Center 7’s “symmetry” does not look like either the World Trade Center 1 or 2’s “symmetry”

As was the case with the World Trade Center 1 and 2, the claim is also self-contradicting when it comes to the World Trade Center 7: Even though the last part of the collapse might appear symmetrical as seen from the north side, the entire collapse is nevertheless asymmetrical, especially when it comes to the top part, the penthouse, which in itself also collapsed asymmetrically.


The claim is therefore:

  • Manipulating
  • Misleading
  • False
  • Self-contradicting


  1. Vidste du at! Spørgsmål til bagsiden af Tamara’s flyer. Kritik og ideer efterlyses!, Michael Højgård Hansen,
  2. NIST NCSTAR 1-9: Volume 1: Chapters 1 – 8, side 261
  3. Static v. Dynamic Loading: Why the WTC Towers Fell So Fast
  4. NIST NCSTAR 1-9: Volume 1: Chapters 1 – 8, side 355
    NIST NCSTAR 1-9: Volume 2: Chapters 9 – Appendix E, side 693
  5. NIST NCSTAR 1-9: Volume 1: Chapters 1 – 8, side 290
  6. NIST NCSTAR 1-9: Volume 1: Chapters 1 – 8, side 95
  7. Video analyse af World Trade Center 7s kollaps
  8. NIST NCSTAR 1-9: Volume 1: Chapters 1 – 8, side 356
  9. Examples of sound pressure and sound pressure levels, Wikipedia
  10. Controlled demolitions

Q & A