For many years, the attacks on the World Trade Center and the Pentagon have been among the most prolific topics for conspiracy theorists around the world. We have analyzed one of the most popular theories on this topic.

September 11, 2001 terrorists captured four scheduled planes departing from three different airports in the eastern United States and heading to California. Two planes were sent to the World Trade Center (WTC) buildings in New York, a third to the Pentagon building near Washington, and a fourth plane crashed in Pennsylvania after the crew and passengers tried to regain control of the plane. As a result of the attacks, in addition to the terrorists, about 3,000 people died. The largest terrorist attack of its time is still shrouded in a huge number of different conspiracy theories, according to which the responsibility for the terrorist attacks is at least partially, and at most completely, not with the militants. One of them is that the towers did not collapse as a result of a terrorist attack, but were blown up from the ground, with conspiracy theorists finding a variety of possible beneficiaries. For example, Yuri Subbotin, who directly calls the events of September 11, 2001 a “grand scam” that was “performed by a company of losers,” lists them in his article for the Parliamentary Gazette, the official publication of the Federal Assembly of the Russian Federation. The list of “suspects” included, in particular, the American military, who were looking for a reason to increase funding, the tenant of the tower, who received significant compensation from insurance companies and the state, intelligence agencies who gained access to correspondence and telephone conversations of Americans, and even “people higher than Bush, those who select and appoint presidents.”

First, let's look at the events in New York that led to the greatest number of victims. According to data September 11 Memorial Museum, the first plane crashed into the North Tower at the 93rd - 99th floor level at 8:46 am, the second - about 17 minutes later into the South Tower at the 77th - 85th floor level. In total, each of the skyscrapers had 110 floors, that is, the airliners damaged their upper parts. However, the South Tower collapsed at 9:59, the North Tower - half an hour later. Moreover, at 17:20, the nearby skyscraper WTC 7, which was not directly damaged by the hijacked aircraft, also collapsed.

Several circumstances immediately attracted the attention of conspiracy theorists, who began to develop various theories based, as it seemed to them, on inconsistencies in the course of events. In particular, many supporters of alternative versions of what happened believe: the skyscrapers fell due to the fact that explosives were placed on the lower floors or basements, because the planes crashing into the upper floors could not lead to the collapse. In 2017, news even spread on the Internet about an alleged CIA agent who admitted to planting bombs, but subsequently it turned outthat the primary source of such publications is a site with fictitious news, and an agent with that name does not exist at all.

The discrepancy, which initially raised questions even among specialists, was explained in 2005 in report National Institute of Standards and Technology (NIST), a division of the US Department of Commerce. According to the investigation, the planes that crashed into the buildings cut utility shafts and burning aviation fuel began to flow down them. This led to fires on the lower floors, which documented eyewitnesses.

The version about the fire that led to the collapse did not convince conspiracy theorists. They drew attention to the fact that burning fuel could not lead to the melting of steel and, consequently, collapse. Them object experts interviewed by Popular Mechanics magazine found that for skyscrapers to collapse, their steel frames only needed to lose some of their structural strength, which requires much less heat. “Steel loses about 50% of its strength at 1,100°F, and at 1,800°F it probably drops below 10%,” says Farid Alfawakhiri of the American Institute of Steel Construction. Although aviation fuel burns at temperatures ranging from 800°F (~430°C) to 1,500°F (~815°C), experts believe flammable furniture, paper and furnishings contributed to the office building fires. As a result, the temperature inside rose above 1,800°F, according to the NIST report.

Satellite image of New York on September 11, 2001

Another argument popular among supporters of alternative versions is the suspiciously large clouds of dust that rose around the WTC buildings at the time of the collapse. Conspiracy theorists claimed that this is a characteristic feature of a controlled explosion, when a building is demolished using explosives placed inside. However, experts in this field don't see there is nothing suspicious in the clouds of dust and debris around the twin towers - the weight of all the collapsing floors falls on the top of the undamaged ones, and that one, unable to absorb the energy, collapses onto the next one. This results in a chain reaction, which experts call pancaking, during which all the air between the floors is "collapses" and comes out along with the dust.

In their arguments, conspiracy theorists use not only observations and, as expert comments show, amateurish conclusions, but also seismograph data. A number of resources draw attention to a seismogram recorded on September 11, 2001 at the Columbia University Research Center, 21 km from the site of the terrorist attack. Scientists allegedly recorded strong tremors even before the collapse of the buildings, which indicates that they were undermined from the ground. At the same time, seismologist Arthur Lerner-Lam, who worked at the scientific center that day asserts: conspiracy theorists took only part of the seismogram to confirm their own guesses. In the full recording, you can easily see that the bursts intensify as the buildings collapse and reach a peak at the moment when the skyscrapers finally fall.

Still, the arguments regarding the twin towers do not answer the question of why the nearby WTC 7 tower collapsed a few hours later. Those who support the version that this building exploded from the ground pay attention to a preliminary report published in 2002 report Federal Emergency Management Agency (FEMA), because this document stated that there was minor damage that the collapse of the Twin Towers caused to this building. However, in a later and more detailed NIST report indicated, that the amount of damage had previously been underestimated: “On about a third of the facade (about ten floors), the building was “hollowed out” approximately 25% in depth,” - reported department specialist. Together with other damage, this led to a “progressive collapse,” when the destruction of part of the structure gradually leads to the fall of the entire building, which was also facilitated by the design features of the seventh tower. The fire that started due to the debris of the twin towers that reached the building also played a role.

The theory surrounding the plane crashing into the Pentagon is the opposite. Conspiracy theorists ask the question: if the World Trade Center buildings collapsed after damage to the upper floors, then why did the direct hit of the airliner on the Pentagon building not lead to its destruction? According to supporters of this version, no plane was sent to the building, but in fact the strike was carried out by a missile (or at least a much smaller plane). Neither photographs from the scene nor the wreckage of the plane found at the scene of the tragedy convince conspiracy theorists.

Reconstruction of the Pentagon after the attacks of September 11, 2001 (2002)

Unlike the glass and metal Twin Towers, the American Army Headquarters is made of reinforced concrete structures. Nevertheless, the damage to the building was very significant, even though, by a happy coincidence, the terrorists flew the plane to that part of the Pentagon that had recently been reconstructed and fortified. It also helped that the plane hit the ground before the collision, thereby dissipating a significant part of the energy. Other arguments from conspiracy theorists disassembled authoritative fact-checking project Snopes.

The research of those who doubt the official version is sometimes embodied in a form close to absurd. There is even a theory that airplanes are completely didn't crash into the World Trade Center buildings, although at least the moment the plane collided with the South Tower hit live on American TV channels. Some documents related to the events of September 11 are still classified, which, coupled with the significance of those events and their emotional overtones, creates excellent opportunities for the development of alternative versions.