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V 1.41
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911Research.WTC7.net site last updated:3/21/13
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Background Attack Aftermath Evidence Misinformation Analysis Memorial

Mushrooming Tops

The Twin Towers' Tops Mushroomed As They Fell

In this photograph of the South Tower about six seconds into its destruction, the mushrooming cloud has already grown to three times the building's width. Note the dust ejection well below the mushrooming top (red arrow).

Both of the twin towers exhibited a mushrooming behavior as they collapsed, resulting in the dispersion of their steel over areas several times the size of their footprints. The mushrooming plumes of dense dust and steel began at the impact zones, and rapidly expanded. By about five seconds into each collapse the diameter of the mushrooming plume was about three times the diameter of the tower.

It is not immediately obvious to what extent the mass of the destroyed portion of the towers was dispersed throughout the clouds. However, several pieces of evidence show that most of the towers' mass landed outside of their footprints in a highly symmetric distribution.

  • Photographs of the collapses show that many pieces of metal were hurled far from the towers, slightly beyond the frontiers of the dust clouds. Although some of that material may be the exterior aluminum cladding, several photos show large assemblies of the perimeter walls hundreds of feet from the towers.
  • The huge hole in WTC 6 seems only explainable as the result of falling pieces of the north wall of the North Tower. The centerline of that hole is approximately 150 feet away from the tower's north wall, giving an indication of the average lateral distance its steel constituents were thrown.
  • The mounds of twisted steel pieces at Ground Zero were nearly as high outside of the towers' footprints as within.
There are no photographs of the mushrooming tops of the towers in FEMA's official report -- just one poor photo of the South Tower early in its collapse -- but there is a nice graphic of the distribution of the perimeter wall column pieces (right).


page last modified: 2006-01-06