World Trade Center 7 Demolition

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World Trade Center 7 Index

47 Story skyscraper destroyed at 5:20 EDT 09/11/2001 (10:20pm Universal Time)

WTC7 was 610ft tall, which is taller than any building in 33 states

The sudden and complete destruction of World Trade Center 7 was not included in the July 2004 911 Commission Report

New York Judge Dismisses Claim Negligent Construction Contributed To WTC 7 Collapse:

9/11’s smoking gun still smoking:

World Trade Center 7 Design and Construction

World Trade Center 7 Building Tenants

World Trade Center 7 Building Damage Prior to Complete Destruction

World Trade Center 7 Building Fire

World Trade Center 7 Demolition Warning

World Trade Center 7 Demolition Videos

World Trade Center 7 Demolition Acceleration

The Top Of World Trade Center 7 Moved Down With A Sudden Onset Of Constant Acceleration

World Trade Center 7 Demolition Seismic Signal

The Destruction Of World Trade Center 7 Generated A Hot Density Current

World Trade Center 7 Demolition Eyewitnesses

World Trade Center 7 Debris Pile

August 21 2008 NIST WTC7 Report (Draft for Public Comment)

November 20 2008 NIST WTC7 Report

World Trade Center 7 NIST Collapse Simulation

NIST Rules Out Diesel Fuel Fires As The Cause Of The Destruction Of World Trade Center 7

NIST Rules Out Structural Damage To WTC7 From WTC1 Debris Impact As The Cause Of The Destruction Of World Trade Center 7

NIST Rules Out Extreme Fire Temperatures As the Cause Of The Destruction Of World Trade Center 7

NIST Rules Out Sub-Standard Building Construction As the Cause Of The Destruction Of World Trade Center 7

World Trade Center 7 Columns Show Evidence Of Cutter Charges

World Trade Center 7 Steel Samples Show Severe Damage Due To A High Temperature Corrosion Attack Which Melted The Steel

Newton’s 3rd Law Was In Effect On 09/11/01:

WTC7 Was was demolished at 5:20 EDT 09/11/2001

[World Trade Center 7 Demolition Warning The BBC reported WTC7's collapse at 5:00 EDT 09/11/2001]

WTC 7 was unlike the WTC towers in many respects. It was a more typical tall building in the design of its structural system. It was not struck by an airplane. The fires in WTC 7 were quite different from those in the towers. Since WTC 7 was not doused with thousands of gallons of jet fuel, large areas of any floor were not ignited simultaneously. Instead, the fires in WTC 7 were similar to those that have occurred previously in several tall buildings where the sprinklers did not function or were not present. These other buildings did not succumb to their fires and collapse because they were of structural designs that differed from that of WTC 7. WTC7 NCSTAR1A Draft p33

"The collapse of WTC7 had a small debris field as the façade was pulled downward, suggesting an internal failure and implosion." fema.gov_p31

"The specifics of the fires in WTC7 and how they caused the building to collapse remain unknown at this time. Although the [Additional WTC7 Diesel Information total diesel fuel on the premises] contained massive potential energy, the best hypothesis [fire causing a complete collapse] has only a low probability of occurrence. Further research, investigation, and analyses are needed to resolve this issue." fema.gov_p7

Demolishing the building so that it collapses straight down into its own footprint ... requires such skill that only a handful of demolition companies in the world will attempt it.

"Amazing, incredible, pick your word. For the third time today; It's reminiscent of those pictures we've all see (too much on television before) when a building was deliberately destroyed by well place dynamite to knock it down." -Dan Rather

"Just before the fall of the North Tower, we saw a large explosion coming from the street-level area around World Trade Center 7."

"In my opinion WTC7 was with the utmost probability brought down by controlled demolition done by experts" -Hugo Bachmann, Professor emeritus for structural analysis and construction at ETH and former Chairman of the Department of Structural Dynamics and Earthquake Engineering, Swiss Federal Institute of Technology.

"WTC7 was with the utmost probability brought down by explosives". -Jörg Schneider, Professor emeritus for structural analysis and construction at ETH

“But truthfully, I don’t really know. We’ve had trouble getting a handle on building No. 7.” -Dr. Sunder September 2005 NIST Report Lead Investigator

"The fire is the most misunderstood part of the WTC collapse. Even today, the media report (and many scientists believe) that the steel melted. It is argued that the jet fuel burns very hot, especially with so much fuel present. This is not true.... The temperature of the fire at the WTC was not unusual, and it was most definitely not capable of melting steel. In combustion science, there are three basic types of flames, namely, a jet burner, a pre-mixed flame, and a diffuse flame.... In a diffuse flame, the fuel and the oxidant are not mixed before ignition, but flow together in an uncontrolled manner and combust when the fuel/oxidant ratios reach values within the flammable range. A fireplace is a diffuse flame burning in air, as was the WTC fire. Diffuse flames generate the lowest heat intensities of the three flame types... The maximum flame temperature increase for burning hydrocarbons (jet fuel) in air is, thus, about 1000 °C - hardly sufficient to melt steel at 1500 °C. But it is very difficult to reach [even] this maximum temperature with a diffuse flame. There is nothing to ensure that the fuel and air in a diffuse flame are mixed in the best ratio... This is why the temperatures in a residential fire are usually in the 500 °C to 650 °C range [Cote, 1992]. It is known that the WTC fire was a fuel-rich, diffuse flame as evidenced by the copious black smoke.... It is known that structural steel begins to soften around 425 °C and loses about half of its strength at 650 °C [Cote, 1992]. This is why steel is stress relieved in this temperature range. But even a 50% loss of strength is still insufficient, by itself, to explain the WTC collapse... The WTC, on this low-wind day, was likely not stressed more than a third of the design allowable... Even with its strength halved, the steel could still support two to three times the stresses imposed by a 650 °C fire." (source - Eagar and Musso, 2001)




Joerg Schneider ETH Professor Emeritus of Structural Engineering

The owner of Jowenko Exposieve Demolitie B.V., a company founded in 1980 which holds Dutch, German and European permits for CD, stated on camera when observing the collapse:

"It starts from the bottom. They simply blew up columns and the rest caved in afterwards. ... This is CD. ... This was a hired job, performed by a team of experts. ... It is without a doubt a professional job. They knew exactly what they were doing.",3,2

WTC7 Work In Progress

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