What has never been in dispute is that the fall of the south tower, just 56 minutes after it had been hit, marked the first time in history that a steel-framed highrise structure had suffered a total collapse due to fire. Never before had such a building suffered even a partial collapse due to fire. At 10:28 AM, the north tower became the second steel-framed highrise structure to suffer a total collapse due to fire.

The twin towers were certainly not the first highrise structures to ever sustain significant damage from a fire. Nor were they the first steel-framed buildings to be struck by errant aircraft. Various buildings around the world, including the Empire State Building, have been hit by airplanes of various size. And countless steel-framed buildings around the world have been hit by U.S.-launched cruise missiles and guided bombs. None of them have ever suffered a complete collapse, even after sustaining multiple impacts.

To explain the unprecedented series of events that unfolded on September 11, 2001, 'experts' trotted out by the media have posited that the photogenic collapses resulted from an historically unique combination of three factors: the initial damage inflicted on the towers by the airplane crashes; the damage caused by what were said to be intense fires; and the unconventional “tubular” design of the twin towers.

These experts, however, have offered no explanation for why the building known as #7 World Trade Center - a conventional steel-framed highrise structure that was not hit by a plane - became, at approximately 5:20 PM on September 11, 2001, the third highrise structure in recorded history to suffer a complete collapse due to fire. FEMA struggled to find an explanation to include in a report on the collapses, but came up short: “The specifics of the fires in WTC 7 and how they caused the building to collapse remain unknown at this time.” (http://www.fema.gov/library/wtcstudy.shtm)

Though dwarfed by the massive twin towers, WTC7 was an imposing structure that would have dominated the skyline of many large cities. Built in 1985, it was a modern, 47-story structure that housed 1,868,000 square feet of commercial office space, much of it occupied by governmental agencies bearing three-letter acronyms, including the CIA.

Some have suggested that WTC7 collapsed due to damage caused by debris from the falling towers, particularly the north tower. That does not appear to be the case, however, since photos and video of the building taken in the hours after the collapse of the towers show that WTC7 was quite intact prior to its collapse. There is also the curious fact that WTC6, which sat between WTC7 and the towers, somehow managed to avoid suffering a complete collapse that day.

Some reports, including the BBC report cited earlier by Ruppert, seemed to imply that the building's foundation had perhaps been "weakened by the earlier collapses." But if that had been the case, WTC7 would not have dropped straight down, as though sinking into the ground; it would have toppled over, taking out neighboring buildings in the process. The BBC report also warned that "more nearby buildings may still fall," as though it had suddenly become commonplace for tall buildings to spontaneously convert themselves into neat piles of debris.

Fires purportedly raged within WTC7 for hours before the building collapsed, but the source of the fires remains largely a mystery, as does the complete failure of the building's modern sprinkler system, which should have been more than adequate to contain any fires. Considering the intense media attention that was focused on lower Manhattan that day, still photos or video footage of WTC7 engulfed in flames are curiously hard to find. Photos of the building taken not long before the collapse (such as the one to the upper right) reveal only small pockets of fire that were confined to two floors.

World Trade Center #7 hit the ground, reduced to a neat pile of rubble, in approximately seven seconds. Like the twin towers, it was in virtual free-fall. Also like the towers, WTC7 collapsed into its own footprint with absolutely uncanny precision. It is no accident that the American people, although bombarded with images of the collapsing towers, have never seen footage of the collapse of WTC7. It is nearly impossible to watch video footage of the collapse and fail to recognize it for what it is: a deliberate, and perfectly executed, controlled implosion. [Click on the two small animated gifs to view video clips of the collapse from two different vantage points.]

The official explanation for the collapse of the twin towers (WTC7 is rarely mentioned) is that the steel and concrete floor slabs, in the areas of the towers damaged by the initial plane crashes, broke free and collapsed down upon the floors below, which then in turn broke free and collapsed, thus creating an alleged 'pancake' effect that quickly gained mass and speed. Once the floors broke free, so the story goes, the outer steel shells of the towers lost structural integrity and collapsed in upon the pancaking floor sections.

There are a few very obvious problems with this 'pancake' theory. First, there is the question of whether fires raged in the towers at sufficient intensity, and for a sufficient amount of time, to cause the failure of the floor trusses. All of the images captured that day show that at the time of the collapses, the towers were billowing copious amounts of thick, black smoke -- indicative not of raging infernos, but of low intensity, smoldering office fires. Transcripts of fire department audiotapes indicate that firefighters on the scene reported only pockets of low intensity fire that posed no danger to the structural integrity of the building.
(http://www.thememoryhole.org/911/firefighter-tape-excerpts.htm)

The graphic to the left, published with the previously cited BBC report, was supposed to help the public understand what caused the collapse of the towers. The illustration, however, contained obvious errors, including the claim that the fires reached "800° C - hot enough to melt steel floor supports." There is no indication that the fires burning in the towers reached such temperatures -- and even if they did, steel doesn't actually melt at 800° C (about 1,500° F); it melts at about 1,500° C (about 2,750° F).

The text of the BBC report contained this curious claim: "the towers' ultimate collapse was inevitable, as the steel cores inside them reached temperatures of 800C - raising questions as to why hundreds of rescue workers were sent into the doomed buildings to their deaths." Actually, if the claim about the core temperatures were true, it would have raised questions as to how hundreds of rescue workers were sent into the doomed buildings to their deaths, since the only way up was through the building cores, where all the stairwells and elevators were located.

Perhaps the best evidence refuting the notion that the fires in the WTC towers were burning at extremely high temperatures can be found through close examination of the pre-collapse photos to the left. Near the center of the gaping entry wound (which looks much different, by the way, than the phantom entry wound in the Pentagon) stands the tragic figure of an apparently young woman still very much alive -- and seemingly unaware that she is clinging to a piece of nearly molten metal.

Technically speaking, the 'pancake' theory does not require that the fires reached temperatures capable of melting steel; it requires only that temperatures were high enough to substantially weaken the steel floor supports. A 1500° F fire could conceivably accomplish that task, if that temperature was maintained for a considerable amount of time. But there is no indication from firefighter reports, survivor reports, or the photographic evidence that there were any fires of that magnitude that burned for any appreciable length of time.

Another problem with the 'pancake' theory is that it fails to address the fate of the cores of the two towers. Contrary to the deceptive BBC graphic, the cores of the WTC towers occupied a considerable portion of the buildings' footprints, as can be seen in the accurately scaled graphic on the lower left, and in the photo on the lower right, taken while the towers were under construction. These configurations of 47 massive steel support columns, heavily cross-braced, were designed to not only be self-supporting, but to support the floors and exterior walls as well.

Even if we accept that the floor slabs somehow ‘pancaked,’ and that the outer steel and aluminum shells then buckled and collapsed, we are left with no explanation of what happened to those massive concrete and steel cores. Clearly, the floor slabs were hardly the wide-open 'pancakes' depicted in deceptive media graphics. In truth, the 'pancake' theory, at best, offers only an explanation of how the floor and exterior wall sections may have collapsed. Even if such an extremely unlikely event had occurred, the end result would not have been a 60-foot-high mound of rubble; it would have been two 137' x 87' x 1,360' towers standing in place of two 208' x 208' x 1,360' towers.

Yet another problem with the ‘pancake’ theory is that it is wholly dependent on a perfectly symmetrical failure of the floor slabs, even though the initial damage to the buildings was clearly asymmetrical, and the fires certainly did not burn uniformly throughout the damaged floors. And yet we know that for the destruction to be complete, the collapse of the initial floor slabs would have had to be perfectly uniform; every point of connection around the perimeter of the core, and every point of connection around the exterior shell, would have had to fail at precisely the same moment in time. And each successive floor would have had to fail in exactly the same perfectly uniform manner, unerringly, all the way down the line. When the ‘pancake’ effect has to course through 110 floors, there isn't really any margin for error. And yet both towers, as we all know, 'pancaked' into oblivion in matching, perfectly choreographed collapses.

Remarkably enough, the two towers somehow collapsed in exactly the same manner even though the initial damage to each tower was quite different. The plane that hit the north tower plowed straight into the center of the north face of the tower, and then straight into the center of the tower's core. The south tower, however, was hit with more of a glancing blow, through the southeast corner of the building, in such a way that the plane likely did minimal damage to the tower's core. Nevertheless, the damage to the south tower may have been more significant than the damage to the north tower. In the north tower, the weight of the upper floors was transferred to the remaining structural elements of the north wall of the tower. But in the south tower, since it was a corner of the building that was blown out, there was nowhere for the load to be transferred. Also, the south tower was hit at a lower elevation, so there was more weight bearing on the damaged area.

It is interesting to note here, by the way, that in both tower crashes, the initial impacts caused structural damage on at least six floors. The south tower was impacted on floors 78-84, and the north tower on floors 93-98. The Pentagon, on the other hand, miraculously sustained impact damage on just two floors.