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Context of 'Between September 3, 2001 and September 7, 2001: WTC Structural Engineer Says Trade Center Designed for 707 Crashing Into It'

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The Office of Special Planning (OSP), a unit set up by the New York Port Authority to assess the security of its facilities against terrorist attacks (see Early 1984), spends four to six months studying the World Trade Center. It examines the center’s design through looking at photographs, blueprints, and plans. It brings in experts such as the builders of the center, plus experts in sabotage and explosives, and has them walk through the WTC to identify any areas of vulnerability. According to New York Times reporters James Glanz and Eric Lipton, when Edward O’Sullivan, head of the OSP, looks at WTC security, he finds “one vulnerability after another. Explosive charges could be placed at key locations in the power system. Chemical or biological agents could be dropped into the coolant system. The Hudson River water intake could be blown up. Someone might even try to infiltrate the large and vulnerable subterranean realms of the World Trade Center site.” In particular, “There was no control at all over access to the underground, two-thousand-car parking garage.” However, O’Sullivan consults “one of the trade center’s original structural engineers, Les Robertson, on whether the towers would collapse because of a bomb or a collision with a slow-moving airplane.” He is told there is “little likelihood of a collapse no matter how the building was attacked.” [Glanz and Lipton, 2004, pp. 227; New York County Supreme Court, 1/20/2004] The OSP will issue its report called “Counter-Terrorism Perspectives: The World Trade Center” late in 1985 (see November 1985).

Entity Tags: Office of Special Planning, Leslie Robertson, Edward O’Sullivan, World Trade Center

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

In the wake of the WTC bombing, the Seattle Times interviews John Skilling who was one of the two structural engineers responsible for designing the Trade Center. Skilling recounts his people having carried out an analysis which found the Twin Towers could withstand the impact of a Boeing 707. He says, “Our analysis indicated the biggest problem would be the fact that all the fuel (from the airplane) would dump into the building. There would be a horrendous fire. A lot of people would be killed.” But, he says, “The building structure would still be there.” [Seattle Times, 2/27/1993] The analysis Skilling is referring to is likely one done in early 1964, during the design phase of the towers. A three-page white paper, dated February 3, 1964, described its findings: “The buildings have been investigated and found to be safe in an assumed collision with a large jet airliner (Boeing 707—DC 8) traveling at 600 miles per hour. Analysis indicates that such collision would result in only local damage which could not cause collapse or substantial damage to the building and would not endanger the lives and safety of occupants not in the immediate area of impact.” However, besides this paper, no documents are known detailing how this analysis was made. [Glanz and Lipton, 2004, pp. 131-132; Lew, Bukowski, and Carino, 10/2005, pp. 70-71] The other structural engineer who designed the towers, Leslie Robertson, carried out a second study later in 1964, of how the towers would handle the impact of a 707 (see Between September 3, 2001 and September 7, 2001). However, the National Institute of Standards and Technology (NIST), following its three-year investigation into the WTC collapses, will in 2005 state that it has been “unable to locate any evidence to indicate consideration of the extent of impact-induced structural damage or the size of a fire that could be created by thousands of gallons of jet fuel.” [National Institute of Standards and Technology, 9/2005, pp. 13]

Entity Tags: World Trade Center, John Skilling

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Leslie Robertson.Leslie Robertson. [Source: Publicity photo]Leslie Robertson, one of the two original structural engineers for the World Trade Center, is asked at a conference in Frankfurt, Germany what he had done to protect the Twin Towers from terrorist attacks. He replies, “I designed it for a 707 to smash into it,” though does not elaborate further. [Chicago Tribune, 9/12/2001; Knight Ridder, 9/12/2001] The Twin Towers were in fact the first structures outside the military and nuclear industries designed to resist the impact of a jet airplane. [Robertson, 3/2002; Federal Emergency Management Agency, 5/1/2002, pp. 1-17] The Boeing 707 was the largest in use when the towers were designed. Robertson conducted a study in late 1964, to calculate the effect of a 707 weighing 263,000 pounds and traveling at 180 mph crashing into one of the towers. He concluded that the tower would remain standing. However, no official report of his study has ever surfaced publicly. [Glanz and Lipton, 2004, pp. 138-139, 366] A previous analysis, carried out early in 1964, calculated that the towers would handle the impact of a 707 traveling at 600 mph without collapsing (see February 27, 1993). In 2002, though, Robertson will write, “To the best of our knowledge, little was known about the effects of a fire from such an aircraft, and no designs were prepared for that circumstance.” [Robertson, 3/2002] The planes that hit the WTC on 9/11 are 767s, which are almost 20 percent heavier than 707s. [Scientific American, 10/9/2001; New Yorker, 11/19/2001]

Entity Tags: Leslie Robertson, World Trade Center

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

A chunk of hot metal being removed from the North Tower rubble about eight weeks after 9/11.
A chunk of hot metal being removed from the North Tower rubble about eight weeks after 9/11. [Source: Frank Silecchia]In the weeks and months after 9/11, numerous individuals report seeing molten metal in the remains of the World Trade Center:
bullet Ken Holden, who is involved with the organizing of demolition, excavation, and debris removal operations at Ground Zero, will later tell the 9/11 Commission, “Underground, it was still so hot that molten metal dripped down the sides of the wall from [WTC] Building 6.” [9/11 Commission, 4/1/2003]
bullet William Langewiesche, the only journalist to have unrestricted access to Ground Zero during the cleanup operation, will describe, “[I]n the early days, the streams of molten metal that leaked from the hot cores and flowed down broken walls inside the foundation hole.” [Langewiesche, 2002, pp. 32]
bullet Leslie Robertson, one of the structural engineers responsible for the design of the WTC, describes fires still burning and molten steel still running 21 days after the attacks. [SEAU News, 10/2001 pdf file]
bullet Alison Geyh, who heads a team of scientists studying the potential health effects of 9/11, reports: “Fires are still actively burning and the smoke is very intense. In some pockets now being uncovered, they are finding molten steel.” [Johns Hopkins Public Health Magazine, 2001]
bullet Ron Burger, a public health advisor who arrives at Ground Zero on September 12, says that “feeling the heat” and “seeing the molten steel” there reminds him of a volcano. [National Environmental Health Association, 9/2003, pp. 40 pdf file]
bullet Paramedic Lee Turner arrives at the World Trade Center site on September 12 as a member of a federal urban search and rescue squad. While at Ground Zero, he goes “down crumpled stairwells to the subway, five levels below ground.” There, he reportedly sees, “in the darkness a distant, pinkish glow—molten metal dripping from a beam.” [US News and World Report, 9/12/2002]
bullet According to a member of New York Air National Guard’s 109th Air Wing, who is at Ground Zero from September 22 to October 6: “One fireman told us that there was still molten steel at the heart of the towers’ remains. Firemen sprayed water to cool the debris down but the heat remained intense enough at the surface to melt their boots.” [National Guard Magazine, 12/2001]
bullet New York firefighters will recall “heat so intense they encountered rivers of molten steel.” [New York Post, 3/3/2004]
bullet As late as five months after the attacks, in February 2002, firefighter Joe O’Toole sees a steel beam being lifted from deep underground at Ground Zero, which, he says, “was dripping from the molten steel.” [Knight Ridder, 5/29/2002]
Steven E. Jones, a physics professor from Utah, will claim this molten metal is “direct evidence for the use of high-temperature explosives, such as thermite,” used to deliberately bring down the WTC towers. [MSNBC, 11/16/2005] He will say that without explosives, a falling building would have “insufficient directed energy to result in melting of large quantities of metal.” [Deseret Morning News, 11/10/2005] There will be no mention whatsoever of the molten metal in the official reports by FEMA, NIST, or the 9/11 Commission. [Federal Emergency Management Agency, 5/1/2002; 9/11 Commission, 7/24/2004; National Institute of Standards and Technology, 9/2005] But Dr. Frank Gayle, who leads the steel forensics aspects of NIST’s investigation of the WTC collapses, will be quoted as saying: “Your gut reaction would be the jet fuel is what made the fire so very intense, a lot of people figured that’s what melted the steel. Indeed it didn’t, the steel did not melt.” [ABC News 7 (New York), 2/7/2004] As well as the reports of molten metal, data collected by NASA in the days after 9/11 finds dozens of “hot spots” (some over 1,300 degrees) at Ground Zero (see September 16-23, 2001).

Entity Tags: Frank Gayle, Joe O’Toole, Ken Holden, Leslie Robertson, Alison Geyh, Lee Turner, William Langewiesche, Ron Burger, World Trade Center, Steven E. Jones

Timeline Tags: Complete 911 Timeline, 9/11 Timeline


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