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V 1.41
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Background Attack Aftermath Evidence Misinformation Analysis Memorial

Squibs

High-Velocity "Demolition Squibs" Are Visible in the Twin Towers' Collapses

A horizontal jet emerges from the northwest face of the North Tower.

Squibs are "blasting caps (initiators) used in the explosive industry to set off high explosives." 1   In discussions of the collapses of the WTC skyscrapers, the term has been appropriated to describe the physical appearance of puffs or jets of dust emerging from buildings during a demolition, caused by the detonation of explosive charges. Several such "squibs" can be seen in videos and photographs capturing the collapses of the North and South Towers.

It has been suggested that the evident squibs could have been added to the photographs and videos after the fact, given that much of this evidence has found its way onto the web via undocumented routes. However, the squibs show up in many diverse videos and photographs, and we have not been able to find any showing the squibs to be absent. A conspiracy of incredible proportions would be required to forge such convincing evidence of squibs in such diverse sources.

LINK

Squibs in the North Tower

Some of the clearest visual evidence of squibs in the North Tower is found in a video bearing the KTLA 5 banner. It shows two very distinct squibs emerging from the North Tower's northwest side, which is in profile on the tower's right, at about two and five seconds into the collapse.

Photographs

The photograph on this page shows two puffs of dust emerging from the walls well below the expanding dust cloud. The position and timing of the one on the northwest (right) face suggest that it is an early stage of the second squib seen in the KTLA 5 video.

The puff in that photo on the northeast (left) side is also visible in the first photograph on this page, but the second squib on the northwest side has already been subsumed by the dust cloud.

The first photograph on this page shows a puff of dust to the right of the visible north corner of the North Tower. That appears to be the beginning of the first squib.

Most of the photographs of the North Tower collapse show it after the second squib has already been subsumed by the dust cloud. We can find no photographs of the North Tower that should show the squibs but do not.

Videos

Other broadcasts besides KTLA 5's showed one or both of the squibs on the tower's northwest wall. This video, taken from close to the North Tower's base, shows the first squib very distinctly as a conical jet of gases that are lighter in color than the expanding dust cloud above.

This video (in wmv format) clearly shows the second squib emerging from the North Tower's northwest side.

This video broadcast by CNN provides one of the most complete records of the North Tower's collapse. It hides the squibs behind the banner, but even so you can distinctly see the second squib through the bluish semi-transparent part of the banner.

Another video shows the two squibs as clearly as the KTLA 5 video, and from a similar vantage point. It is not available on this site, but is found on the video 911: The Greatest Lie Ever Sold.

LINK

Squibs in the South Tower

South Tower puffs
Broad dust ejections emerge from mechanical equipment floors of the South Tower.

Squibs are also apparent in the South Tower's collapse, though they don't appear to be as energetic as the two North Tower squibs examined above. In this photograph a red arrow highlights a row of puffs of dust emerging from the southeast face of the South Tower about 10 floors below the bottom of the zone of total destruction.

The same squibs are clearly visible in the first two collapse sequences of this ABC News video montage of the South Tower collapse.

LINK

Gravity-Collapse Explanations

Defenders of the gravity collapse theory consistently invoke the explanation that the ejections of dust are caused by pancaking floors squeezing out air and dust. The Popular Mechanics article attacking 9/11 Truth contains the following passage.

Like all office buildings, the WTC towers contained a huge volume of air. As they pancaked, all that air--along with the concrete and other debris pulverized by the force of the collapse--was ejected with enormous energy. "When you have a significant portion of a floor collapsing, it's going to shoot air and concrete dust out the window," NIST lead investigator Shyam Sunder tells PM. Those clouds of dust may create the impression of a controlled demolition, Sunder adds, "but it is the floor pancaking that leads to that perception."

NIST's final Report on the Twin Towers mentions the piston theory to attempt to explain away the ejections:

The falling mass of the building compressed the air ahead of it, much like the action of a piston, forcing material, such as smoke and debris, out the windows as seen in several videos.

There are several problems with this explanation, which we designate the piston theory.

  • The squibs contain thick dust of a light color, apparently from crushed concrete and gypsum. But these materials would not have been crushed until the pancaking floors above impacted the floor emitting the squib. Thus the dust would not be produced until the air was already squeezed out, so there was no source of the dust for the squib.
  • The squibs emerge from the facade 10 to 20 floors below the exploding rubble cloud inside of which the tower is disintegrating. The thick clouds appear to contain the pulverized concrete of the floor slabs, which was the only concrete component of the tower. But the piston theory requires that the floors have already pancaked down to the level of the squib, making them unavailable for the production of the concrete dust more than 10 floors above.
  • The piston theory requires a rather orderly pancaking of the floor diaphragms within the intact sleeve of the perimeter wall. Such a process should have left a stack of floor diaphragms at the tower's base at the end of the collapse. But there was no such stack. In fact, it is difficult to find recognizable pieces of floor slabs of any size in Ground Zero photographs.
  • The North Tower exhibits three distinct sets of squibs at different elevations of the building. Each set is visible as two distinct squibs on the same floor, one emerging from about the horizontal center of each of the tower's two visible faces. This pattern is is far too focused and symmetric to be explained by the piston theory, which would produce similar pressures across each floor and over successive floors.
  • The pancaking of floors within the perimeter wall would have created underpressures in the region above the top pancaking floor. But we seen no evidence of dust being sucked back into the tower.


References

1. Fireworks Glossary, usfireworks.biz,

page last modified: 2013-03-20