Twin towers construction history. Destruction of the World Trade Center towers in New York

16 years have passed since the terrible fall of the Twin Towers in America on September 11, 2001. But the memories of that day still haunt millions of Americans. The destinies of many people were changed forever.

How many people died?

In addition to American citizens, representatives of other countries were also among the dead. Among the dead were 96 citizens from the former Soviet Union. At the end of the search and rescue operations, experts stated that approximately 10,000 fragments of human bones and tissues were found at the site of the fall of the buildings, which significantly increases the initial statistics of the incident. Fragments were found much later, in 2006, when Deutsche Bank was being reconstructed. The average age of the dead was 40 years.

Course of events

On September 9, terrorists hijacked four planes and were able to fly two of them to the twin towers of the World Trade Center in New York, and one to the Pentagon. The remaining plane crashed in Pennsylvania after the passengers were able to overpower the hijackers.

A day that began with clear blue skies ended in a twisting mass of smoldering smoke from the twisted metal where the huge mall buildings once stood. As a result of this incident, 2977 people died.

People's memory

The tragedy of September 11 occurred almost two decades ago. A quarter of Americans are too young to remember this disturbing event. “I have three children who do not remember the incident at all, since they were not born yet. But we, of course, do not want to forget, even as we live and face new challenges,” says one of the Americans.

So, in remembrance of that day, 23 images hang here, serving as reminders of what no American should forget. The tragedy has acquired enormous proportions. Witnesses to what happened can tell a lot.

The Twin Towers of the World Trade Center were symbols for New Yorkers. For decades, people looked up to them, and the structures stood firm. It was an encouraging sight. According to the American’s recollections, he visited the towers many times and looked at them many times. On the morning of September 11, he had just finished voting in Brooklyn when he looked up and saw one of the towers on fire. Just minutes later, a second plane crashed into another tower. Something was wrong.

When President George W. Bush was informed of the tragic incident, he was at a school event. The expression on his face, captured in the photograph, expresses almost every emotion. At that time, none of the government members knew what serious consequences this terrorist attack had for the country.

Major fire

The impact of the two fire jets was devastating. It broke the steel structure of the towers and contributed to fires that ultimately led to the destruction of the buildings. Warplanes took to the skies. Every non-military flight in US airspace was ordered to land.

Thousands of people were truly trapped on the upper floors of the towers. Many died instantly when the planes crashed into the buildings, and many more died when fires broke out and towers began to collapse. Some citizens jumped out of windows to escape the fire and smoke. A total of 2,606 people died in the towers.

The weather was wonderful, the sky was bright blue. The wind carried a massive plume of smoke over the city and New York Harbor. “Manhattan looked as if 10 megatons had exploded in it,” British writer Martin Amis later wrote.

Terrible outcome

The structure of the towers was so damaged that their collapse was an inevitable consequence of the impact. At the time, however, no one expected such a terrible outcome. People in the streets around the World Trade Center fled in panic. Buildings began to collapse one by one and fill the streets with rubble and dust.

The fires burned for hours and smoldered for days in a mass of twisting steel and rubble. Lower Manhattan, below 14th Street, will later be closed to non-rescue traffic.

The area around the World Trade Center was a scene of complete devastation. Smoke and dust hung in the air. Countless cars, trucks and rescue vehicles were destroyed.

Destroyed tower structure

The feeling of tragedy was everywhere. The New York City Fire Department lost its chaplain, Reverend Michael, who was killed by falling debris.

Little remains of the elegant facades of the Twin Towers, which Japanese architect Minoru Yamasaki designed to include narrow window openings and soaring arches.

Two 110-story towers overlooking the city were compressed into a twisted mass of molten metal. Welders spent months cutting away steel so the damaged structure could be dismantled.

Rescue work

The New York City Fire Department rushed to the scene and suffered incredibly high casualties as they tried to rescue people from the burning towers. As a result, 343 brigade members died during the suppression operation. The strong men could not stand it; tears kept running down their cheeks.

In the following days, rescuers arrived in New York from neighboring cities and states. The sight of the bodies in the rubble brought indescribable horror. A contrasting sign of indomitability was the moment when American flags were raised over the site of the tragedy.

Loved ones have posted photos of missing friends and family members in the desperate hope that they might be alive.

Tragedy brought everyone together

A city coming together is something many Americans have never seen. Citizens lined the streets to cheer on the National Guard and rescue workers as they arrived in Manhattan for the mission that became known as Ground Zero.

The Americans were consumed by a thirst for revenge. Soon national troops were stationed in Afghanistan.

These attacks were not limited to New York. The Pentagon was also hit hard, killing 125 people.

The view of the Pentagon was also terrifying, but the military headquarters building itself did not collapse.

A new tower rose to Ground Zero along with a memorial. This gave many Americans a sense of pride when it opened. But this is not enough to make people forget this terrible day, on which many lives were cut short. America itself at this moment changed radically.

The new architecture of lower Manhattan stands proudly above New York City. Here is the famous Oculus, from where you can once again look at the endless space of the city from above.

Commemorative Memorial

In memory of the enormous losses of the 2001 terrorist attacks, a museum was opened in New York, the exhibition of which is constantly expanding. According to American media reports, the memorial was visited by more than 900 thousand people.

Here you can see fragments of the steel frame of skyscrapers, a mangled fire truck that participated in putting out the fire, many photographs depicting those killed on that ill-fated day and stunning videos.

Viewers can also see the jacket of a fighter who took part in the elimination of the largest terrorist Osama bin Laden, and a symbolic coin that belonged to the CIA officer who tracked down the dangerous terrorist.

The exhibits on display at the memorial provide citizens with an opportunity to pay tribute to the courage of the many people who sacrificed their lives for their country.

Finite element model of the World Trade Center floor to evaluate the building's structural system

The dimensions of the structure in plan are 63.4x63.4 m, the rigidity cores are 26.8x42.1 m. The WTC towers were designed as a “pipe-in-pipe” (stem structural design) in order to create a continuous space on the floors, not divided walls or columns. This was achieved due to the fact that the outer wall of the tower, in fact, was a set of columns installed side by side, taking on the main vertical load, while the wind load fell mainly on the power columns located in the center of the tower (stiffness core). Starting from the tenth floor, each wall of the tower was composed of 59 columns, with 49 load-bearing columns installed in the center of the tower. All elevators and stairwells ran within the rigid core, leaving a large free space between the core and the perimeter of the tower to accommodate offices.

The floor covering structure was 10 cm lightweight concrete, laid on permanent formwork made of profiled flooring. The corrugated sheeting was laid on secondary (auxiliary) trusses (beams), supported by the main trusses, transmitting the load to the central and peripheral columns. The main trusses had a length of 11 and 18 meters (depending on the span), and were laid in increments of 2.1 m, and were attached from the outside to lintels connecting the peripheral columns at the level of each floor, and from the inside to the central columns. The floor was secured through elastic dampers designed to reduce the impact of building vibrations on the people working in it.

This truss system allowed optimized load redistribution of the floor diaphragms between the perimeter and core, with improved performance between the different materials of flexible steel and rigid concrete allowing the moment structure to transfer influence into compression on the core, which also mainly supported the transmission tower.

The towers also included an "outrigger truss" located between the 107th and 110th floors, which consisted of six trusses along the longitudinal (long) axis of the core and four along the short (transverse) axis, which served to redistribute loads and increase the overall stability of the building, and also to support the antenna spire, which was installed on only one of the towers. NIST determined that this structure played a key role in the sequence of events leading to the complete destruction of the towers.

Possibility of resisting fire and aircraft hits

Like all modern high-rise buildings, the WTC towers were designed and built to withstand a normal fire. Many fire safety features were incorporated during the design and construction phase, and others were added after a 1975 fire that consumed six floors before being contained and extinguished. Tests carried out before the disaster showed that the steel structures of the towers met or even exceeded current fire resistance requirements.

Software engineers building structures, who designed the World Trade Center, took into account the possibility that a plane could collide with the building. In July 1945, a B-25 Mitchell bomber became disoriented in fog and crashed into the 79th floor of the Empire State Building. A year later, a twin-engine C-45 Beechcraft collided with the skyscraper at 40 Wall Street, and another plane came close to another collision with the Empire State Building.

NIST stated that “American Building Standards do not include requirements for the stability of buildings when struck by an aircraft. … and thus buildings are not designed to withstand the impact of a fully fueled commercial airliner.” , nevertheless, the designers and architects of the World Trade Center discussed this problem and recognized its importance. Leslie Robertson, one of the chief engineers of the World Trade Center, recalled that the scenario considered was that a Boeing 707 jet would hit the building, disorientated in fog and flying at relatively low speed in search of JFK Airport or Newark Liberty Airport. John Skilling, another WTC engineer, said in 1993 that his subordinates carried out an analysis that showed that the biggest problem if the WTC towers collided with a Boeing 707 would be that all the plane's fuel would end up inside the building and lead to a "terrible fire." and many casualties, but the building itself will remain standing. FEMA wrote that the World Trade Center buildings were built to withstand a collision with a Boeing 707 jet airliner, which weighs 119 tons and has a speed of about 290 km/h, much less in weight and speed than the aircraft used in the September 11 attacks.

NIST found in the archives a three-page report summarizing research that simulated a Boeing 707 or Douglas DC-8 hitting a building at 950 km/h. The study showed that the building should not collapse as a result of such a hit. But, as NIST experts noted, “the 1964 study did not model the effect of a fire caused by jet fuel spraying into a building.” NIST also noted that in the absence of initial calculations used to model the situation, further comment on this topic would be largely “speculation.” Another document found by NIST was a calculation of the period of oscillation of a building if a plane were to hit the 80th floor of the World Trade Center tower, but it made no assumptions about the fate of the building after the impact. A property risk assessment report prepared for Silverstain Properties considered the possibility of an aircraft hitting the World Trade Center towers as unlikely but possible. The report's authors cited WTC structural engineers who said the towers should have withstood a collision with a large passenger plane, but burning fuel flowing from the plane to ground level would have damaged the building's skin. Some documents related to the analysis of the scenario of an aircraft hitting the towers were lost as a result of the destruction of WTC 1 and WTC 7, which contained documents from the Port Authority of New York and New Jersey and Silverstain Properties.

Aircraft hitting towers

The terrorists sent two jet airliner Boeing 767, American Airlines Flight 11 (767-200ER) and United Airlines Flight 175 (767-200). The North Tower (1 WTC) was hit at 8:46 am by Flight 11, between the 93rd and 99th floors. Flight 175 crashed into the south tower (2 WTC) at 9:03, between floors 77 and 85.

The Boeing 767-200 airliner has a length of 48.5 m, a wingspan of 48 m, and carries on board from 62 tons (-200) to 91 tons (-200ER) of aviation fuel. The planes crashed into the towers at very high speed. Flight 11 was traveling at approximately 700 km/h when it struck the north tower; Flight 175 crashed into Southern at a speed of about 870 km/h. In addition to the fact that the hits caused severe damage to the supporting columns, they caused the explosion of approximately 38 tons of aviation fuel in each tower, which led to the almost immediate spread of a large fire on several floors containing office furniture, paper, carpeting, books, and other flammable materials. The shock wave from hitting the north tower spread down to the first floor, along at least one high-speed elevator shaft, and broke glass on the first floor, causing injuries to several people.

Fire

The lightweight construction of the towers and the lack of solid walls and ceilings led to the fact that aviation fuel spread throughout a fairly large volume of buildings, leading to numerous fires on several floors close to the impact areas of the aircraft. The aviation fuel itself burned out within a few minutes, but the combustible materials in the building itself kept the fires burning intensely for another hour or an hour and a half. It is possible that if more traditional structures had been in the path of the aircraft, the fires would not have been so centralized and intense - aircraft debris and aviation fuel could have remained primarily in the peripheral area of ​​the building, rather than penetrating directly to its central part. In this case, the towers would probably have survived, or in any case, would have stood significantly longer.

Development of the situation

• 9:52 - A fire department helicopter radios that “large pieces of the building may fall from the upper floors of the south tower. We are seeing large parts of the building in limbo.”

• 9:59 - a helicopter reports that the south tower is falling.

Helicopters also reported the development of the situation with the north tower of the World Trade Center.

• 10:20 - Fire Department helicopter reports that the upper floors of the north tower may be unstable.

• 10:21 - it is reported that the south-eastern corner of the tower is warped, and that the tower is beginning to lean towards the south.

• 10:27 - it is reported that the roof of the north tower may collapse at any minute.

• 10:28 am - The fire department receives a report that the north tower has collapsed.

Overloaded dispatchers and poor communications have left New York's fire and police departments experiencing big problems ensuring timely interaction, both with their units and with each other. As a result, the fire brigades located in the towers did not receive orders to evacuate and 343 firefighters died when the buildings collapsed.

WTC towers collapse

The south tower collapsed at 9:59 a.m., 56 minutes after impact. The north tower stood until 10:28, 102 minutes after the plane hit it. The collapsed towers created a huge cloud of dust that covered much of Manhattan. In both cases, a similar process occurred, the upper damaged part of the building collapsed onto the lower floors. Both towers fell almost vertically, although there was a significant deviation from the vertical of the top of the south tower. Debris and dust were also observed flying from the windows of the building below the rapidly advancing collapse zone.

Tower collapse mechanism

The NIST investigation found that because the planes hit the towers in different ways, the process of destruction of the north and south towers was also slightly different, although it was generally the same in both cases. After being hit by the planes, the internal power columns were seriously damaged, although the external columns suffered relatively little damage. This caused a serious redistribution of the load between them. The upper power structure of the towers played a significant role in this redistribution.

Aircraft that struck buildings stripped fire-resistant coatings from large portions of steel structures, exposing them to direct fire. In the 102 minutes preceding the collapse of the north tower, the temperature of the fire, although well below the melting point of the metal, had reached a sufficient magnitude to cause the weakening of the strength columns in the center of the building, which began to deform and bend under the weight of the upper floors. The NIST report describes this situation as follows:

A similar situation occurred in the south tower (the internal power columns were seriously damaged). The peripheral columns and floor structures of both towers were weakened by the fire, causing the floors on the damaged floors to settle and placing significant stress on the peripheral columns towards the interior of the building.

At 9:59, 56 minutes after impact, the settling floor caused severe inward bending of the outer columns on the east side of the south tower, the upper load structure transferred this bending force to the central columns, causing them to collapse and begin the collapse of the building, the top of the tower in the process deviated towards the damaged wall. At 10:28 a.m., the south wall of the north tower buckled, causing approximately the same sequence of events. As a result of the subsequent collapse of the upper floors, the complete destruction of the towers became inevitable, due to the enormous weight of the part of the buildings that were located above the damage zone.

The reason that the northern tower stood longer than the southern one was a combination of the following three factors: the area where the aircraft hit the northern tower was higher (and the weight of the upper part of the building, accordingly, less), the speed of the aircraft that hit the tower was lower, in addition, the aircraft hit floors whose fire protection has previously been partially improved.

The theory of complete progressive collapse

Ruins of the South Tower (right) and North Tower (left), as well as other World Trade Center buildings

A huge cloud of dust obscured the collapsing towers, making it impossible to determine the exact duration of the destruction based on visual evidence.

Because the NIST report focuses primarily on the mechanisms of the initial collapse, it does not address the subsequent complete collapse of both WTC towers. Initial analyzes explained the collapse by saying that the kinetic energy of the falling upper floors was much greater than what the floors could withstand, which also collapsed, adding kinetic energy to the falling building. This scenario was repeated with increasing speed until the towers were completely destroyed. Although this is the most widely accepted view among civil engineers, it has been criticized for not taking into account the resistance of the underlying structures, which should have slowed, or even stopped, the collapse of the towers.

7 WTC building collapse

FEMA's initial study was inconclusive, and the collapse of 7 WTC was not included in the final NIST report released in September 2005. Except for the letter published Metallurgical Journal, which suggested that the building's steel frame could have melted in a fire, no other studies of this issue were published in scientific journals. The 7 WTC crash was investigated separately from the 1 WTC and 2 WTC crashes, and in June 2004, NIST released a working report that contained several hypotheses about what happened. One hypothesis was the destruction of one of the building's critical support columns, caused by fire or large debris from falling towers, leading to "disproportionate collapse of the entire structure."

NIST diagram showing the bending of Column 79 (outlined in orange) that began the progressive collapse of the building.

The order of destruction of 7 WTC in the diagram from the 2004 NIST preliminary report. Column 79 is marked with a circle in the center of the red zone.

NIST's 7 WTC fall model. In the first part of the video, columns 81, 80 and 79 are depicted from left to right.

On November 20, 2008, NIST published the final report on the fall of 7 WTC. The NIST report cited fire as the main cause of destruction, along with a lack of water for firefighters and the automatic fire suppression system to fight the fire. NIST reconstructs the sequence of events as follows: At 10:28 a.m., debris from the falling 1 WTC caused damage to the nearby 7 WTC. Fires also broke out, likely from burning debris from 1 WTC. Firefighters immediately arrived at 7 WTC, but at 11:30 they discovered that there was no water in the fire hydrants to fight the fire - the water came from the city water supply system, destroyed as a result of the falls of towers 1 WTC and 2 WTC. New York City Fire Department ( English), fearing for the lives of firefighters in the event of the destruction of 7 WTC, at 14:30 he recalled the firefighters and stopped fighting to save the building. The fire was observed on 10 floors from the 7th to the 30th, and on floors 7-9 and 11-13 the fire got out of control. Thermal expansion of the beams heated to approximately 400 °C around column 79 in the eastern part of the building in the area of ​​the 13-14th floor led to the failure of the fire-weakened floors adjacent to column 79 from the 13th to the 5th floor. The destruction of the floors deprived column 79 of horizontal support, and it began to bend, which was the immediate cause of the complete destruction of the building within a few seconds. The bending of column 79 led to the transfer of the load to columns 80 and 81, which also began to bend, as a result of which all the floors associated with these columns were destroyed up to the top of the building. The falling floors destroyed truss 2, which led to the fall of columns 77, 78 and 76. As a result of the increased load transferred from the bent columns, the falling of fragments of the floors from above, and the lack of horizontal support from the destroyed floors, all internal columns from east to west began to bend sequentially. Following this, in the area of ​​floors 7-14, the outer columns began to bend, to which the load was transferred from the lowered inner columns and the center, and all floors above the bent columns began to fall down as a single whole, which completed the final destruction of the building at 17:20.

Some authors criticized the city authorities' decision to locate the 7 WTC headquarters on the 23rd floor Office of Emergency Situations(English) Office of Emergency Management ). It was believed that this could have been a significant factor in the destruction of the building. Particularly noted was the placement of large diesel fuel tanks in the building, which were supposed to serve to power emergency power generators. NIST concluded that diesel fuel did not play a role in the destruction of the building, but the rapid evacuation of the Office of Emergency Management was a contributing factor to the poor communication between various agencies and the loss of control over the situation. The main cause of the building's destruction was fire; damage from debris from the falling 1 WTC accelerated the fall of the building, but NIST calculations showed that 7 WTC would have collapsed from an uncontrolled fire alone.

Progress of investigations

First reaction

The destruction of the World Trade Center towers came as a surprise to construction engineers. “Before September 11,” the magazine wrote New Civil Engineer“We quite sincerely could not imagine that a structure of such a scale could suffer such a fate.” Although the damage from the aircraft was severe, it only affected a few floors of each building. The challenge for engineers was to figure out how such local damage caused the complete progressive collapse of three of the world's largest buildings. In an October 2001 BBC interview, English architect Bob Halvorson aptly predicted that there would be much "debate about whether the World Trade Center could have collapsed the way it did." A full analysis would include architectural and structural plans of the World Trade Center, witness testimony, videos of the destruction, debris survey data, etc. Underscoring the complexity of the task, Halvorson said the destruction of the World Trade Center towers is "far beyond the realm of normal experience."

Research credibility

Immediately after the disaster, there was a situation of uncertainty as to who had sufficient authority to conduct an official investigation. Contrary to the practice found in air crash investigations, clear procedures for investigating building collapses simply did not exist.

A short time after the disaster at the base Institute of Civil Engineers(English) Structural Engineers Institute (SEI)) American Society of Civil Engineers(English) American Society of Civil Engineers ASCE), a working group was created, which also involved specialists American Institute of Steel Construction(English) American Institute of Steel Construction ), American Concrete Institute(English) American Concrete Institute ), National Fire Protection Association and Engineering Communities Fire Protection (English) Society of Fire Protection Engineers ) . ASCE also invited the Federal Emergency Management Agency (FEMA) to join the work of this group, which later received joint ASCE-FEMA control. This investigation was subsequently criticized by American engineers and lawyers, however, the authority of the above-mentioned organizations was sufficient to conduct the investigation and to provide access to the disaster site for the group's experts. One of the most poignant aspects of the investigation was that clearing the disaster site actually led to the destruction of the remaining components of the building. Indeed, when NIST published its final report, it noted a “lack of physical evidence” as one of the main problems of the investigation. Only a fraction of a percent of the building's remains remained available for investigation after the clearance work was completed, with a total of 236 individual steel fragments recovered.

FEMA released its report in May 2002. Although NIST had already announced its involvement in the investigation in August of that year, in October 2002, under increasing public pressure for a more detailed investigation, Congress passed a bill to create a new group under NIST, which published its report in September 2005.

FEMA's "stack of pancakes" theory

In its early investigations, FEMA developed a theory to explain the collapse of the World Trade Center towers, called the "stack of pancakes" theory. pancake theory). This theory was defended by Thomas Iga and was widely covered by PBS. According to this theory, the connection between the lintels supporting the floor and the columns of the building failed, causing the floor to collapse on the floor below, placing loads on its structure that it was not designed for. Some individual publications have proposed other sets of factors that caused the collapse of the towers, but overall this theory has been accepted by most.

Fires remained the main key factor in this theory. Thomas Iga, a professor of materials science at MIT, described the fires as "the most baffling part of the collapse of the World Trade Center towers." Although the fires were initially thought to have "melted" the steel structures, Iga stated that "the temperatures of the fires in the WTC towers were unusually high, but still certainly not sufficient to cause melting or severe softening of the steel." The combustion of aviation kerosene typically results in large fires, but these fires do not have very high temperatures. This led Iga, FEMA and other researchers to believe that there was a weak point, and this point was identified as the floor anchorage to the building's supporting structure. Due to the fire, these fastenings weakened and, when they collapsed under the weight of the floor, collapse began. On the other hand, the NIST report states completely and unequivocally that these fasteners were not destroyed. Moreover, it was their strength that was one of the main reasons for the collapse, since through them a force was transmitted to the peripheral columns, bending the columns inward.

At temperatures above 400-500 °C there is a sharp decrease in the tensile strength and plasticity limit (3-4 times), at 600 °C they are close to zero and load bearing capacity steel is running out.

NIST report

Organization of the study

As a result of mounting pressure from experts, construction industry leaders and family members following the release of the FEMA report, National Institute of Standards and Technology The Commerce Department's NIST conducted a three-year, $24 million investigation into the destruction and collapse of the World Trade Center towers. The research included a series of experiments, in addition, leading specialists from many third-party organizations were involved in it:

• Structural Engineering Institute of the American Society of Civil Engineers (SEI/ASCE)
• Society of Fire Protection Engineers (SFPE)
• National Fire Protection Association (NFPA)
• American Institute of Steel Construction (AISC)
• Council on Tall Buildings and Urban Habitat (CTBUH)
• Structural Engineers Association of New York (SEANY)

Scope of study and its limitations

The NIST study's scope was limited to examining the "sequence of events from the moment the aircraft was hit until the collapse of each tower began" and also included "a small analysis of the structural behavior of the tower structure once the conditions for its failure had been reached and collapse was imminent." Just like many other engineers working on this issue, NIST experts focused on aircraft hits on towers, simulating the effects of hits such as structural failure, fire spread, etc., with great precision. high degree details. NIST has developed several very high-detail models of various building components, such as floor-supporting lintels, and entire buildings have also been modeled, but at a lower level of detail. These models were static, or quasi-static, and included deformation simulations, but did not include simulations of the movement of structural elements after they were separated from each other. Thus, NIST models are useful for understanding why towers begin to collapse, but do not provide a way to model the collapse itself.

Parallel investigations

In 2003, three engineers from the University of Edinburgh published a report suggesting that the fires alone, even without taking into account the destructive effects of aircraft strikes, were enough to completely destroy the WTC towers. In their opinion, the design of the towers made them uniquely vulnerable to large fires covering several floors at once. When the NIST report was released, Barbara Lane and the English engineering company Arup criticized its conclusion that the destruction caused by aircraft hits was a necessary factor for the collapse of buildings .

Criticism

Some engineers have offered insight into how the towers collapse by developing animated collapse sequences based on dynamic computer models and comparing the resulting results with video footage of the disaster site. In October 2005, the magazine New Civil Engineer relative to a computer model created by NIST. In response, NIST enlisted Colin Bailey of the University of Manchester and Robert Planck of the University of Sheffield to create the computer visualizations needed to work to correct models of tower collapses and bring those models into full agreement with observed events.

Other buildings

Parts of the outer wall of the north tower opposite the remains of the 6 WTC building, which received very serious damage as a result of the fall of the north tower. In the upper right corner are the remains of the 7 WTC building.

On September 11, 2001, the entire World Trade Center complex and the small Greek Orthodox Church of St. Nicholas, which stood on Liberty Street opposite the south tower of the World Trade Center, were destroyed. In addition, many buildings surrounding the complex were damaged to one degree or another.

Consequences

Clearing the disaster site

The huge pile of rubble at the World Trade Center site continued to burn and smolder for another three months, with attempts to control the fire unsuccessful until a significant amount of debris and debris had been removed. The clearance was a very large-scale operation, coordinated by the Department of Construction (DDC). A preliminary clearing plan was prepared on September 22 by Controlled Demolition Inc. (CDI) from Phoenix. Mark Lozo, president of CDI, particularly emphasized the importance of protecting the clay wall (or "bathtub") that protected the WTC foundation from being flooded by the waters of the Hudson. The cleanup was carried out around the clock, involving a large number of contractors, and cost hundreds of millions of dollars. In early November, after about a third of the debris had been cleared, the city government began reducing the involvement of police and firefighters in the cleanup as they searched for the remains of the dead, and shifted priorities to trash removal. This caused objections from firefighters. As of 2007, demolition of some of the buildings surrounding the WTC was ongoing, while construction of the WTC replacement, memorial complex, and Freedom Tower continued.

Controlled demolition versions

There is a theory that the WTC towers could have been destroyed as a result of a planned, controlled demolition, and not as a result of being hit by aircraft. This theory was rejected by NIST, which concluded that no explosives were involved in the collapse of the towers. NIST stated that it did not perform tests to look for explosive residues of any kind in the debris because it was not necessary:

12. Did the NIST investigation look for evidence of the WTC towers being brought down by controlled demolition? Was the steel tested for explosives or thermite residues? The combination of thermite and sulfur (called thermate) "slices through steel like a hot knife through butter."

NIST did not test for the residue of these compounds in the steel.

The responses to questions number 2, 4, 5 and 11 demonstrate why NIST concluded that there were no explosives or controlled demolition involved in the collapses of the WTC towers.

In a 2008 report, NIST also analyzed the WTC Tower 7 explosion hypothesis and concluded that the explosion could not have caused the observed effects. In particular, the smallest amount of explosive that could destroy Column 79 would produce a noise of 130-140 decibels at a distance of 1 km from 7 WTC, but such noise was not noticed by either sound recording equipment or witnesses. This theory has become a prominent part of most of all the "conspiracy theories" that arose as a result of the events of September 11.

Notes

1. Relatives gather at ground zero to mark 9/11, The Associated Press/MSNBC(September 9, 2007). Retrieved November 3, 2007.
2. PartIIC - WTC 7 Collapse (pdf). NIST Response to the World Trade Center Disaster. National Institute of Standards and Technology (April 5, 2005). Archived from the original on March 4, 2012. Retrieved November 1, 2006.
3. Hamburger, Ronald, et al.(pdf). Federal Emergency Management Agency. Archived
4. Snell, Jack, S. Shyam Sunder NIST Response to the World Trade Center Disaster (pdf). National Institute of Standards and Technology (November 12, 2002). Archived from the original on March 4, 2012. Retrieved July 27, 2006.
5. Chapter 1 // . - NIST. - P. p. 6.
6. National Construction Safety Team Final Report on the Collapse of the World Trade Center Towers. - NIST.
7. Barrett, Devlin Steel type in WTC met standards, group says. The Boston Globe. Associated Press (2003). Retrieved May 2, 2006.
8. Glanz, James and Eric Lipton. The Height of Ambition (English) , The New York Times(8 September 2002).
9. Adam Long. PILOT LOST IN FOG; SCENE OF PLANE CRASH LAST NIGHT AIRPLANE CRASHES INTO SKYSCRAPER Ceiling Reduced by Fog, The New York Times(24 May 1946).
10. (pdf). NIST NCSTAR 1-1 Pages 70-71 Archived
11. Leslie E. Robertson. Reflections on the World Trade Center (English) // The Bridge. - National Academy of Engineering, 2002. - Vol. 32. - No. 1. Archived from the original on February 28, 2010.
12. Fahim Sadek. NIST NCSTAR 1-2. Baseline Structural Performance and Aircraft Impact Damage Analysis of the World Trade Center Towers. - NIST, September 2005. - pp. 3-5, 308.
13. Nalder, Eric. (English) The Seattle Times (27-02-1993).
14. Ronald Hamburger, et al. World Trade Center Building Performance Study. - Federal Emergency Management Agency. - P. 1-17.
15. NIST's Working Hypothesis for Collapse of the WTC Towers (Appendix Q). NIST (June 2004). Archived from the original on March 4, 2012. Retrieved December 21, 2007.
16. NIST was informed by the Port Authority that the documents cited were destroyed in the collapse of WTC 1 and the WTC owners documents held in WTC 7 were also lost.
17. Lew, H. S.; Richard W. Bukowski and Nicholas J. Carino Design, Construction and Maintenance of Structural and Life Safety (pdf). NIST NCSTAR 1-1 Page 71. National Institutes of Standards and Technology (2006). Archived from the original on March 4, 2012. Retrieved October 15, 2007.
18. Jane's All the World's Aircraft Boeing 767. Jane's (2001). Retrieved August 19, 2007.
19. Field, Andy A Look Inside a Radical New Theory of the WTC Collapse. Fire/Rescue News (2004). Retrieved July 28, 2006.
20. Gross, John L., Therese P. McAllister Structural Fire Response and Probable Collapse Sequence of the World Trade Center Towers (pdf). Federal Building and Fire Safety Investigation of the World Trade Center Disaster NIST NCSTAR 1-6 Archived
21. Wilkinson, Tim World Trade Center - Some Engineering Aspects (2006). Archived from the original on March 4, 2012. Retrieved July 28, 2006.
22. Lawson, J. Randall, Robert L. Vettori. NIST NCSTAR 1-8 - The Emergency Response P. 37. NIST (September 2005). Archived from the original on March 4, 2012.
23. McKinsey Report - Emergency Medical Service response. FDNY/McKinsey & Company (August 9, 2002). Archived from the original on August 26, 2011. Retrieved July 12, 2007.
24. McKinsey Report - NYPD (August 19, 2002). (inaccessible link - story) Retrieved July 10, 2007.
25. NY Firefighters attack Giuliani. BBC News, July 12, 2007 http://news.bbc.co.uk/2/hi/americas/6294198.stm
26. Bažant, Zdeněk P.; Yong Zhou (2002-01-01). "Why Did the World Trade Center Collapse? - Simple Analysis". J Engrg Mech 128 (1): pp. 2-6. DOI:0.1061/(ASCE)0733-9399(2002)128:1(2) . Retrieved 2007-08-23.
27. Bažant, Zdeněk P.; Mathieu Verdure (March 2007). "Mechanics of Progressive Collapse: Learning from the World Trade Center and Building Demolitions." J Engrg. Mech. 133 (3): pp. 308-319. DOI:10.1061/(ASCE)0733-9399(2007)133:3(308) . Retrieved 2007-08-22.
28. Cherepanov, G.P. (September 2006). "Mechanics of the WTC collapse". Int J Fract(Springer Netherlands) 141 (1-2): 287-289. DOI:10.1007/s10704-006-0081-8. Retrieved 2007-10-07.
29. Hayden, Peter WTC: This Is Their Story. Firehouse Magazine (April 2002). (inaccessible link - story)
30. Observations, findings and Recommendations (pdf). World Trade Center Building Performance Study, (Chapter 8.2.5.1). Federal Emergency Management Agency. Archived from the original on March 4, 2012. Retrieved July 28, 2006.
31. Barnett, J.R.; R.R. Biederman, R.D. Sisson Jr. An Initial Microstructural Analysis of A36 Steel from WTC Building 7. Feature: Letter. The Journal of Materials (2001). Archived from the original on March 4, 2012. Retrieved May 12, 2006.
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37. Barrett Wayne Grand Illusion: The Untold Story of Rudy Giuliani and 9/11. - Harper Collins. - ISBN 0-06-053660-8
38. Replying to Giuliani
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Twin Towers: History, Pride and Tragedy of America

Buildings, like people, have something in common. Some live simple lives unnoticed by most and, when they die, remain in the memory of only their closest relatives. Others are visible, admired or hated; at least many people know them. When they die, they remain part of history, living in the minds of millions, even after passing into eternity, influencing the living.

It was the second option that fate chose for the famous skyscrapers, the Twin Towers in New York. Blown up as a result of the terrorist attack on September 11, 2001, these buildings seem to continue to exist: everyone knows them, remembers them, they continue to be replicated in thousands of photographs. In the end, they still subtly influence the life of a huge metropolis, and the United States as a whole.

Construction of the Twin Towers

It's easy to build, difficult to negotiate. Any building in the world, even country house, is born not on a construction site, but in the minds of its creators. The World Trade Center in New York was no exception, the architectural and visual dominance of which were two skyscrapers, immediately called towers: North and South.

The idea of ​​​​building a grandiose complex was born in the USA during the Second World War. By 1944, it became clear that as a result, there was only one state left in the Western world that managed not only to maintain its economic power, but to significantly strengthen it, especially against the backdrop of destroyed Europe and Japan. America became this state. It did not take much intelligence to understand the simple truth: in the coming decades the country will become a superpower and will develop rapidly. And it will need a large financial and trading complex.

But a lot of time passed before the idea began to turn into reality. There were two main reasons.

The first is the inflamed arms race and the Cold War, which required colossal financial investments.

The second is a clash of economic interests of several influential US groups, as well as two states, New Jersey and New York. In addition, the construction of the Center assumed the emergence of new skyscrapers that would exceed the height of the Empire State Building, the pride of the city, the tallest building in the world. The financial groups that controlled this building were not at all eager for the emergence of a formidable competitor.

And only by the beginning of the 60s were all commercial, image and financial issues managed to be settled. The Rockefeller brothers, David and Nelson, played a significant role in this. Using their influence, connections and money, the brothers began to build the World Trade Center in Lower Manhattan.

The entire complex, including the twin towers, was designed by several powerful design companies, but Japanese-American Minoru Yamasaki was chosen as the lead architect, the father of the project.

Before starting work on this project, Yamasaki completed several serious works in different cities of the United States, although he was not one of the most venerable professionals in the country. A proponent of Gothic modernism, strongly influenced by the architecture of Le Corbusier, the Japanese drew attention to the small ancient twin towers in the Italian town of San Gimignano, taking them as a model for his task.

And the master’s task was simple: to create something that would have 5 times more office space than the Empire State Building. After going through several possible options, Yamasaki came to the final one: two slender towers with a square cross-section, shaped like parallelepipeds.

The entire construction process can be divided into the following stages:

• design: 1962 - 1965;
• cleaning and preparing the area for construction - from March to August 1966;
• August 1966 - start of excavation work, excavation of soil for the base of the towers;
• installation of the last load-bearing element of the buildings - December 1970 (North Tower), July 1971 (South Tower);
• grand opening of the complex - April 4, 1974.

At the end of construction, the towers turned out to be the tallest buildings in the world, each with 110 floors. The upper elevation of the South was 415 meters, the North was 2 meters higher, and it was also decorated with an antenna with an elevation of 526.3 meters.

Among other things, the appearance of the towers launched a real race of skyscrapers that began in the world. Looking ahead a little, we can say that on the site of the fallen “candles” the Americans built a new World Trade Center, which is crowned by the tallest building in the Western Hemisphere. However, now it is only the fourth in a cohort of giant buildings.

The unusual face of the Twin Towers

Continuing the analogy we started, we can say that, like people, outstanding buildings also have their own records and unique life events. They are also available at the Yamasaki Towers. Here are some of them:

• During the construction of the buildings, deep 20-meter pits were dug to get to the “bedrock” rock. The earth from the excavations was used for an artificial embankment, on which several buildings of the World Financial Center were subsequently built.
• The design of the towers is based on hundreds of large and small steel pipes, creating a special frame that is resistant to wind and seismic vibrations.
• The facade of the buildings is replete with a huge number of narrow windows, only 56 cm wide. Yamasaki suffered from a fear of heights, and designed the windows so that any person, approaching the window sill, could easily rest against the slopes of the window opening, which would create a special feeling of reliability.

• Each of the towers had 103 elevators, of which 6 were freight. Some passenger elevators were high-speed, some were ordinary. For the transition from the first to the second, platforms on the 44th and 78th floors were used.
• Immediately after the construction of the towers, they received derogatory criticism from the world's leading architects. The city residents didn’t really like the buildings either. But gradually they got used to them and even began to be proud of them. The Eiffel Tower in Paris had approximately the same fate.
• The first attempt to destroy the buildings was made in 1993. Then, in the garage of the North Tower, underground, a truck with more than half a ton of explosives was blown up.

In the end, the terrorists managed to blow up unusual buildings. But, having destroyed them, did they destroy the very idea, the desire of man to conquer, to create something unusual? After all, it is inherent in human nature itself.

And, perhaps, the daring Frenchman Philippe Petit said this very well, who in August 1974 managed to walk 8 times in a row (!) on a rope stretched between two towers, while dancing and even lying down: “Lying on the rope, I saw very close above you is a seagull. And I remembered the myth of Prometheus. Here, at this height, I invaded her space, proving that a person can be compared with a bird ... "

Ten years ago, 19 men trained by Al Qaeda carried out a coordinated terrorist attack on the United States. It took several years to develop the plan for the terrorist attack. Terrorists simultaneously hijacked 4 large passenger planes with the intention of using them to destroy the most famous landmarks in the United States, taking as many lives as possible. Three planes reached their targets, the fourth crashed into a field in Pennsylvania. In one day, these acts of mass murder killed about 3,000 people from 57 countries. Of these, more than 400 died - firefighters, police and ambulance crews. This event received the maximum coverage in the entire history of the media, and even ten years later it is difficult to look at these photographs. The attacks and the response to them have greatly shaped the world we live in today, which is why it is important to look at these photographs and remember what happened that day. This post is the second of three on the September 11 terrorist attacks.

1. View of the Statue of Liberty and Manhattan covered in clouds of smoke and dust from Jersey City, New Jersey, September 15, 2001. (AP Photo/Dan Loh)

2. Smoke pours from a hole in the wall and from the upper floors of the north tower of the World Trade Center in New York after the collision of American Airlines Flight 11. (AP Photo/Richard Drew)

3. United Airlines Flight 175 moments before impact with the South Tower of the World Trade Center. The north tower is already on fire. (Reuters/Sean Adair)

4. Explosion in the south tower during the collision of United Airlines Flight 175 in New York, September 11, 2001. The plane crashed into the building at a speed of 945 km/h. (Reuters/Sean Adair)

5. Airplane collision with the south tower of the World Trade Center. There were 56 passengers on board (including 5 hijackers). (Spencer Platt/Getty Images)

6. The explosion of 3800 liters of fuel remaining on board the plane during a collision with the south tower of the World Trade Center in New York. (AP Photo/Ernesto Mora)

7. Two women, holding each other, look at the World Trade Center buildings burning after a terrorist attack. (AP Photo/Ernesto Mora)

8. The burning twin towers are visible behind the Empire State Building. (AP Photo/Marty Lederhandler)

9. A cloud of smoke from the World Trade Center buildings in lower Manhattan. Photo from a USGS satellite flying over the area around 9:30 a.m. on Tuesday, September 11, 2001. (AP Photo/USGS)

10. People hanging from the windows of the North Tower of the World Trade Center after the attack. (Jose Jimenez/Primera Hora/Getty Images)

11. A man jumps to his death from the north tower of the World Trade Center filled with smoke and flames. (Jose Jimenez/Primera Hora/Getty Images)

12. A man jumps from the upper floors of the burning north tower of the World Trade Center. (AP Photo/Richard Drew)

13. A man jumps from the north tower of the World Trade Center. (AP Photo/Richard Drew)

14. A Pentagon surveillance camera captured the explosion that resulted from the collision with a hijacked American Airlines plane with 58 passengers and six crew on board on September 11, 2001. (AP Photo)

15. Flames and smoke erupt from the Pentagon building after the explosion. (AP Photo/Will Morris)

17. Medics treat victims near the Pentagon after a hijacked airliner crashed into the southwest corner of the building. (Reuters/U.S. Navy Photo/Journalist 1st Class Mark D. Faram)

19. Smoke billows from the World Trade Center towers after two hijacked planes crashed into them during the terrorist attack on New York. (Mario Tama/Getty Images)

20. At 9:59 a.m. on September 11, 2001, 56 minutes after the impact, the south tower of the World Trade Center begins to collapse. (AP Photo/Gulnara Samoilova)

21. The South Tower of the World Trade Center collapses, and the rubble buries the surrounding streets. (AP Photo/Richard Drew)

22. Police officers and pedestrians run for cover during a terrorist attack in New York. (Doug Kanter/AFP/Getty Images)

23. People covered in dust walk through the rubble near the World Trade Center in New York on September 11, 2001. (AP Photo/Gulnara Samoilova)

24. Maru Stahl of Somerset, Pennsylvania, shows a photo he took of the crash site of United Airlines Flight 93. The plane crashed near Shanksville, and Stahl, hearing the explosion, headed to the crash site and took a photo before rescuers cordoned off the area. The plane crashed in Pennsylvania shortly after the attacks on New York. (Reuters/Jason Cohn)

25. FBI aerial photograph of the crash site of Flight 93 in Shanksville, Pennsylvania, taken on September 12, 2001. The Boeing 757 was flying from Newark, New Jersey, to San Francisco when it made a sharp turn near Cleveland and crashed in Shanksville, Pennsylvania. 44 people died. The plane was one of four that were part of the 9/11 attack plan and the only one that failed to reach its target. (AP Photo/FBI)

26. Firefighters and rescue workers investigate the crash site of Flight 93 near Shanksville, Pennsylvania. (AP Photo/Tribune-Democrat/David Lloyd)

27. At 10:28 a.m. on September 11, 2001, 102 minutes after the plane struck, the north tower of the World Trade Center in New York collapses. (AP Photo/Diane Bondareff)

28. Collapse of the World Trade Center tower on September 11, 2001 in New York. (Jose Jimenez/Primera Hora/Getty Images)

29. A New York Police Department photo shows ash and smoke billowing across Manhattan as the North Tower of the World Trade Center collapses. (AP Photo/NYPD, Det. Greg Semendinger)

30. Dust, smoke and debris fill the air as the World Trade Center tower falls on September 11, 2001 in New York. (Reuters/Shannon Stapleton)

31. Dust, smoke and ash envelop neighboring buildings after the fall of both World Trade Center towers on September 11, 2001 in New York. (AP Photo/NYPD, Det. Greg Semendinger)

32. People are leaving the collapsed towers to escape the smoke and dust. As a result of the September 11, 2001 terrorist attack in New York, both 110-story towers of the World Trade Center collapsed. (AP Photo/Suzanne Plunkett)

33. The North Tower of the World Trade Center turns into a cloud of dust and debris half an hour after the fall of the South Tower on September 11, 2001. The photo was taken from Jersey City, New Jersey, across the Hudson River. (Reuters/Ray Stubblebine)

34. People make their way through the rubble near the ruins of the World Trade Center on September 11, 2001 in New York. (AP Photo/Gulnara Samoilova)

35. A priest helps people after the fall of the World Trade Center towers in New York on September 11, 2001. (AP Photo/Gulnara Samoilova)

36. People cover their faces from the dust as they cross the Brooklyn Bridge to get away from the cloud of dust and smoke that covered Manhattan after the terrorist attacks. (AP Photo/Daniel Shanken)

37. People on the street near the Twin Towers on September 11, 2001. (Mario Tama/Getty Images)

38. A sheriff's deputy treats a woman injured during the September 11 terrorist attack on the World Trade Center in New York. (AP Photo/Gulnara Samiolava)

39. A man sobs as he watches the World Trade Center tower fall in New York on September 11, 2001. (AP Photo/Shawn Baldwin)

40. A firefighter rests on a bench in lower Manhattan while working at the site of the fall of the Twin Towers on September 11, 2001. (AP Photo/Matt Moyer)

41. Construction debris and ashes from the fall of the World Trade Center towers as a result of the terrorist attack fill the streets of Manhattan, turning the city into a picture of the Apocalypse. Buildings collapsed, burying thousands of people in the rubble. (AP Photo/Boudicon One)

42. A fireman calls rescuers to help clear the wreckage of the World Trade Center. The photo was taken on September 15, 2001. (Reuters/U.S. Navy/Journalist 1st Class Preston Keres)

43. The chassis of one of the hijacked planes lies on the street next to the destroyed buildings of the World Trade Center in New York, September 11, 2001. (Reuters/Shannon Stapleton)

44. Firefighters search for survivors under the rubble of the Twin Towers after the September 11, 2001 terrorist attack. (AP Photo/Matt Moyer)

45. Light barely breaks through the clouds of smoke and ash at the site of the collapse of the World Trade Center towers. (AP Photo/Baldwin)

46. ​​New York firefighters extinguish building 7 of the World Trade Center, destroyed along with the Twin Towers during the terrorist attack on September 11, 2001. (Reuters/Mike Segar)

47. A group of firefighters near the ruins of the south tower of the World Trade Center in New York, September 11, 2001. (Reuters/Peter Morgan)

48. Debris covers the tracks in the New York City Subway tunnel on lines 1 and 9 at the Cortlandt Street Station under the World Trade Center. New York City transportation officials said the damage was so severe that more than one mile of tunnel had to be rebuilt. (AP Photo/New York City Transit)

49. Rescuers carry out a search and rescue operation for victims as they descend into the rubble of the World Trade Center on Friday, September 14, 2001. (Reuters/U.S. Navy/Photographer's Mate 2nd Class Jim Watson)

50. A man stands in the ruins of the World Trade Center towers and tries to call survivors, asking if anyone needs help. (Doug Kanter/AFP/Getty Images)

World News

The eleventh day of September 2001 went down in history as a tragedy on a global scale, dealing a crushing blow to the faith of citizens of a democratic community in their own safety and integrity. Terrorist attack of September 11, 2001 killed 2 thousand 752 people

The most important signs of the work of demolitions in the World Trade Center

The rapid and strictly vertical collapse of skyscrapers (this happens when a building is targeted for demolition), despite the fact that the “twins” collapsed vertically, the third building was also completely razed to the ground - WTC#7, which was not rammed by planes, all structures were practically destroyed " into crumbs" (this effect is achieved only with professional explosive dismantling), experts heard on the recordings the sounds of several explosions seconds before the collapse, which came from the first floors, captured on many amateur videos, wisps of smoke and flashes almost forty floors below the level where the planes crashed , numerous fragments of glass, steel and human remains found over a very wide radius, including on the roofs of houses, many vertical supporting beams were cut diagonally (such a preparatory procedure is also typical for dismantling), remains of combustion of the Thermate substance, usually used for military purposes for thermal cutting of steel (found at the site of rubble independent experts), numerous traces of steel supporting structures melted to a lava-like state. The combustion continued even on the fifth or sixth day and was recorded on NASA aerial photographs (airplane kerosene is not capable of creating such high temperatures - a minimum of 1500oC is required!).

The names of specialists who disagree with the official White House version are impressive - leading scientists in the fields of history, defense, psychology, philosophy and applied sciences. Conducted research confirms the opinion that the World Trade Center buildings in New York were destroyed by controlled explosions, and the authorities' version of the Pentagon attack does not stand up to criticism. Scientists are convinced that the government not only allowed the September 11 attacks, but also staged them for political purposes.


The names of the people who made sensational accusations are striking:
Robert M. Bowman is the former director of Project Star Wars, the US Air Force space defense program (101 combat missions).

Fred Burks is a translator for many American presidents and people who are familiar with the political cuisine of America first-hand.

Lloyd de Moos is director of the Institute of Psychohistory, president of the International Psychohistorical Association and editor of the Journal of Psychohistory.

Eric Douglas is a New York architect, chairman of the independent committee reviewing projects for the restoration of the World Trade Center.

James Fetzer is a renowned scientist, professor at McKnight University (Minnesota), former US Marine Corps officer, author and editor of more than 20 academic publications, co-founder of the S9/11T group.

Robert Fritzius - electronic engineering, radar and telecommunications specialist.

Daniel Ganser is a historian, representative of the University of Basel (Switzerland).

Michael Gass - explosives specialist (US Air Force), sapper, author of mine clearance techniques.

Kenyon Gibson is a former naval intelligence officer and the author of several books on the events of 9/11.

Rich Hellner - air traffic control, dispatcher.

Don Jacobs is the former Dean of the School of Education and Professor of Education at Northern Arizona University.

Andrew Johnson is a physicist, computer scientist, and software developer.

Stephen Jones is a physics professor, co-founder of the S9/11T group, and creator of the website.

Peter Kirsch is a renowned pathologist.

Wayne Madsen is a investigative journalist and former intelligence officer.

Richard McGinn is professor of linguistics, Ohio University.

Morgan Reynolds is a professor of economics, a leading economist at the Department of Labor during the George H. W. Bush administration, and director of the criminal justice center at the National Center for Policy Analysis.

E. Martin Schotz - historian, psychiatrist, mathematician.

Glenn Stanish is a pilot and director of the Airline Pilots Association.

Andreas von Bülow - ex-Deputy Minister of Foreign Affairs of Germany, head of the German intelligence services, member of parliament for 25 years.

Jonathan Wilson is a specialist in criminology, University of Winnipeg (Canada).

This is far from full list, allowing you to get an idea of ​​the level of professionalism of the people who made accusations against the American government. What gives them the right to question the official White House narrative? The answer to this question can be found on the website www.st911.org, where 20 reasons for distrust of President Bush are published.

The 9/11 Commission refused to review vast amounts of testimony and evidence. Even the former director of the FBI stated that the commission in question was hushing up real events.
The recording of the interrogations of the dispatchers on duty on September 11 was deliberately destroyed - the tapes were broken by hand, the film was torn into small fragments, and its fragments were thrown into various trash cans.
Congressional investigators discovered that an FBI informant provided housing for two hijackers in 2000. When the commission wanted to question this citizen, the FBI not only refused to comply with this request, but also hid the informant. According to some reports, the FBI took such steps after receiving appropriate instructions from the White House.
A retired U.S. Air Force lieutenant colonel and former director of the Star Wars project recently issued the following statement: “If our government had done nothing that day except to ensure that the normal procedure required in such cases was followed, the Twin Towers would still be standing. "Thousands of dead Americans would still be alive. Our government's actions are treason!"


Recently declassified documents show that in the 60s, the American high command developed a plan to blow up AMERICAN aircraft and commit terrorist attacks against US citizens on American soil.

The US Defense Department, responsible for the safety of citizens, has been conducting exercises for many years, developing a version of using kamikaze aircraft against the World Trade Center buildings and other American skyscrapers. “Various types of civil and military aircraft were used to practice actions in the event of a possible terrorist attack. In other words, the Pentagon used REAL EXISTING AIRCRAFT to simulate an attack on high-rise buildings, including the Twin Towers. Why did the department “turn out to be unprepared” - remains a question.
In addition, the military was practicing options for similar attacks on the Pentagon.
On the morning of September 11, American defense and intelligence agencies conducted military exercises to combat terrorism using REAL aircraft and fake "radar tags", which misled the controllers.
It was on the morning of September 11 that the government conducted maneuvers simulating a terrorist air attack on the World Trade Center.
Despite the government's claims of ignorance of the terrorist plane, the US Secretary of Transportation testified to the commission that Vice President Cheney personally monitored the pilots of the ill-fated Flight 77 many miles before the vehicle approached the Pentagon.
The third building of the World Trade Center (building No. 7) collapsed on September 11, despite the fact that it was not hit by terrorist planes. It collapsed as if it had no walls or ceilings. Before the tragedy, only small local fires were noted in the building. This is the only steel building frame structure in the world, destroyed due to fire, which cannot happen by definition.
According to a number of FBI employees, the World Trade Center buildings collapsed as a result of the explosion of bombs planted inside it.
MSNBC claims that police believed that one of the explosions at the World Trade Center could have been caused by a truck full of explosives located inside the building. In their opinion, explosive devices could have been placed both in the building itself and in its immediate vicinity.
The explosions may have been caused by "bombs" and "secondary devices," the New York City Fire Department's safety chief said. Firefighters believed there were bombs in the building.
A spokesman for the National Demolition Association said the collapse of the Twin Towers resembled a "classically planned demolition of a building."
Eyewitnesses of the explosion claim that the explosions occurred much BELOW the area hit by the planes. Moreover, they happened BEFORE the first plane hit the building.
According to the testimony of a certain police officer, destructive explosions on the upper floors occurred at intervals of 15 minutes. The building collapsed only after that.

Scientists managed to collect and systematize dozens of facts that were “overlooked” by the authorities, distorted their essence, or (what is especially scary) did not find a place on the pages of official reports. Every aspect of the official version raises doubts among the inquisitive and literate reader who wants to know the truth about what happened.

Terrorist attack or controlled explosion?


According to representatives of science, "the fire (fire) could not lead to the destruction of the steel structures of the building." Supporters of the official (government) version of the tragic events keep silent about this fact. Moreover, according to a report signed by the Directorate of the National Institute of Standards and Technology (2005), the steel structures of the buildings were destroyed allegedly as a result of fires. At the same time, science does not know a single similar fact.

Interestingly, the towers were designed with the possibility of air attack in mind and were built with the design strength to withstand a collision with such a colossus as a Boeing 767.

"They were designed to withstand all sorts of impacts, including tornadoes, bombings or collisions with huge airliners," says Hyman Brown, project manager for the Twin Towers (2001).

The theory about the destruction of the building as a result of fire and melting of the supporting steel structures is also absurd. According to experts, the destruction of skyscrapers is reminiscent of a “controlled detonation,” when a certain amount of explosives is placed in supporting structures and triggered in the desired sequence.

During a controlled detonation, the destruction of a building occurs suddenly - at first there is nothing, but the next moment the structure disintegrates. Steel structure with high temperature can't suddenly break. This happens gradually - the horizontal beams begin to sag, and then the vertical ones become deformed steel columns.

But the video footage that captured the destruction of the towers did not record similar processes even on the floors located above the hole left by the plane. In addition, the art of controlled detonation of a high-rise building is to ensure that the exploded skyscraper does not fly apart in all directions, but “sags” in such a way that the debris remains exclusively at the construction site. This is what happened with the towers.

According to Marc Loisier, president of a major controlled detonation company, such an explosion "must be completely planned, and the explosives must be placed in a certain order." All 110 floors of the twin towers collapsed very neatly. In an unplanned explosion, construction debris would have covered the entire area, but this did not happen.

In a controlled detonation, the remains of a building fall to the surface at free fall speed, which does not happen in a random disaster. To do this, demolitionists first place explosives under the support systems of the lower floors, so the upper ones fall down, meeting virtually no resistance.

According to the commission's report, the south tower collapsed in 10 seconds, which corresponds to a controlled explosion. Moreover, this technique makes it possible to “cut” load-bearing steel structures into pieces of a certain length, which was recorded in New York. The huge cloud of dust that formed at the site of the towers after the explosion also serves as indirect evidence of a controlled explosion. Colonel came to this conclusion engineering troops USA John O'Dowd. “It seemed that the air at the site of the World Trade Center explosion was saturated with cement dust.”

Another proof of a planned explosion - great amount molten steel at the site of the collapse of the towers. Thus, Peter Tully, head of the construction company Tully Construction, and Mark Loisier reported “lakes of molten steel” discovered at the site of collapsed buildings in underground elevator shafts. Meanwhile, the collision of the plane with the building and the subsequent ignition of aviation fuel could not lead to the formation of temperatures at which steel structures begin to melt. The mystery of the explosion of the Twin Towers, according to scientists, still remains unsolved. What about the government? It remains inactive, refusing to divulge information that contradicts the official theory.

Shortly after the events of September 11, more than 500 New York City fire and ambulance personnel gave oral testimony pointing out some of the inconsistencies noted during the response to the terrorist attack. The New York City mayor's office did everything possible not to make these facts public or to refute them.

Only in August 2005, The New York Times and a group of relatives of the victims, as a result of a lengthy trial and a number of appeals, managed to force the mayor's office to publish the mentioned testimonies of direct witnesses to the death of the WTC.

Witness accounts refute government theories, proving that the events of 9/11 were a well-planned terror attack.

Unfortunately, American officials do not want to conduct an independent investigation, establish the truth and punish those responsible. Why is this happening? Who benefits from this and why? These questions remain unanswered, but the public is not satisfied with the Bush administration's position, and the S9/11T group does not intend to stop its activities. Soon we will expect new details that will reveal the essence of these tragic events and the hypocrisy of officials. If the statements of American scientists turn out to be true, “controlled detonation” may well lead to an uncontrollable reaction from society - not only the American one, but also the world one. And then the authors of the biggest hoax in the history of mankind may not be in trouble, writes Konstantin VASYLKEVICH

THE BEHAVIOR OF THE US SECURITY SERVICES PROVES IMMEDIATELY THAT THE 9/11 TERROR ATTACKS IN THE USA ARE THEIR HANDS.

In their haste to blame Muslims for this, in their haste to strike at Afghanistan, they made an investigation against the intelligence services themselves impossible.

“The US government announced the creation of a new structure within its intelligence services (numbering 170,000 people with an annual budget of $37 billion), designed to coordinate the efforts of different departments, as well as for the extrajudicial physical destruction of terrorists around the world, that is, for the murder of persons undesirable to the “world behind the scenes” (previously, the CIA hid such operations, now there is no need for this: it is enough to declare someone a “terrorist”). This was a new step in the global war “against terrorism,” declared after the terrorist attacks of September 11, 2001, which gave the United States a free hand to forcefully subjugate the entire planet. Even then, many democratic countries adopted laws facilitating surveillance, preventive arrests, electronic wiretapping, and the abolition of the secrecy of bank deposits; Measures of political censorship were introduced in democratic media, including the closure of sites on the Internet that “distribute hate propaganda.” That is, the extrajudicial repressions of the special services against their own citizens were significantly expanded.” "TOMORROW", N30, 2002."

The BUSH administration used the Boeing attack as a pretext for invading Iraq and Afghanistan in order to realize its dream of world hegemony under the banner of the fight against terrorism.