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911Research.WTC7.netsite last updated:09/09/2015
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This site has been available to people investigating the September 11th attack since April of 2003. Early versions of this site were distributed on CD, starting at version number 0.50. Embarrassing grammatical errors are plentiful in early versions, and there are some factual errors due to incomplete fact-checking.

This page lists factual errors detected in versions since 0.50 uncovered by subsequent fact-checking.

Note that the version number appears in light gray just above the copyright notice and date stamp on the lower left panel of most pages.

  • Before V0.58: the page Crash-Proof Passport stated: Note that not a single positive identification was made between human remains at the World Trade Center site and any passengers on either Flight 11 or Flight 175. This appears to be false in light of reports by New York City's chief medical examiner.

  • Before V0.60: the page Phone Calls page stated there were dozens of calls from Flight 93, instead of 13.

  • Before V0.62: the page timeline page had an incorrect time for the scrambling of the F-15s from Otis.

  • Before V0.63: the page Volume of Dust stated: That the clouds expanded to ten times the volume of the towers within 20 seconds of the initiation of their collapses is a conservative estimate. This appears to overstate the expansion of the dust cloud. The current page gives a fivefold expansion in 30 seconds as a conservative estimate.

  • Before V0.64: the page Collapsing Buildings stated: prior to September 11th, no steel framed building had ever undergone total collapse due to any cause or combination of causes other than controlled demolition. Also the page Collapsing Skyscrapers stated: .. no steel framed high-rise in history had ever collapsed of its own weight due to any cause or combination of causes -- be they bombings, severe fires, earthquakes, or hurricanes. Subsequent research turned up the case of a 21-story steel frame office building that "totally collapsed" because of the 8.1 magnitude 1985 Mexico City earthquake. Since a 21-story building qualifies as a high-rise but not a skyscraper, high-rise was changed to skyscraper in the second passage.

  • Before V0.70: the page Fire Severity stated: The North Tower continued to produce prodigious quantities of smoke, and it continued to darken until its collapse, but it never became as black as the smoke from the South Tower preceding its demise. It is clear that the North Tower's smoke darkened dramatically before the second impact, and that it darkened more up to its sister's collapse. The evidence suggests, however, that the smoke may have lightened after that collapse. The page also stated: Significant emergence of flames from the buildings, another common feature of large office fires, was not observed. To the contrary, the patch of fire on the 105th floor of the North Tower after the South Tower collapse could qualify as significant emergence of flames. There were also emergent flames on the southwest side of the North Tower soon after the impact of Flight 11, and emergent flames on the east corner of the South Tower for a short time after the impact of Flight 175.

  • Before V0.84: the page The Fires stated: 800º C is near the maximum temperature at which hydrocarbons will burn in air at sea level: 825º C. This implies that 825º C is a theoretical upper limit on flame temperatures in hydrocarbon fires, when in fact such fires may reach much higher temperatures when fed pressurized or pre-heated air. Of course in a building fire, there is unlikely to be any pressurized air, and pre-heating of air is limited by the fact that the fires continuously draw in fresh air. An exception is flash-over, in which pre-heated gases suddenly ignite, sometimes reaching temperatures over 900º C. This is a momentary phenomenon, however, and will not produce sustained fire temperatures this high.

  • Before V0.870: pages under the The Pentagon Strike analysis page failed to acknowledge the eyewitness accounts of a large jetliner approaching the Pentagon before the explosion.

  • Before V0.872: the page Vanishing Jetliner stated: Flight 77 also contained several tons of people and luggage. Yet immediately after the crash there was virtually no debris on the lawn outside the Pentagon that looked anything like jetliner parts. This ignores the identifiable scrap, an important piece of evidence.

  • Before V0.882: Numerous pages contained spelling and grammatical errors.

  • Before V0.885: Several of the pages listed on the collapses image archive page gave times for photographs relative to the start of the collapses that were incorrect, particularly for the North Tower collapse.

  • Before V0.886: the page Facts about the Famous World Trade Center stated that Building 7 was first occupied in 1975, when in fact construction did not begin until 1985. This error was in the source from which we compiled the table.

  • Before V0.890: the page The Twin Towers' Fires and Their Possible Effects stated: As the jet fuel burned off and the fires became less severe, the columns would have cooled and regained any lost strength. This ignores the possibility, however unlikely and inconsequential, that the steel could have been tempered by elevated temperatures.

  • Before V0.906: the pages Pentagon Strike Conclusions and No Intact 757 Hit the Pentagon stated that the evidence ruled out that a 757 crashed into the Pentagon on 9/11/01. This conclusion was nuanced to include the qualifier intact.

  • Before V0.926: the talk The Pentagon Attack Frame-Up, which concludes that whatever struck the Pentagon was not a Boeing 757, made several points that we feel involve overly simplistic inferences from the evidence. For example, the pages that suggest the lawn was undisturbed by the crash based on photographs fail to account for the forshortening of the ground close to the buildings in those photographs. Since the talk is a historical document and its co-author, who asks not to be named, stands by its conclusion, we have appended commentary to the bottom of certain slides, while preserving the structure of the original slides.

  • Before V0.933: the page fireball stated: This photograph shows a large fireball centered at the middle of the damaged part of the Pentagon's facade. In fact, the fireball is centered about 15 feet to the right of the center of damage. Since the fuel tanks of a 757 are located in its wings, the shape and location of this fireball raises questions about its origin. In fact, the fireball's shape and location correspond to that of one of the landscaping trees, supporting the simple conclusion that the mysterous fireball is just the tree rapidly combusting.

  • Before V0.933: two pages about the Pentagon CCTV frames erroneously described the cropping of a version of the frames with timecodes and one without timecodes. The second page stated: The famous set of five video frames from a Pentagon security video camera in a parking structure later appeared in the form of uncropped images of slightly higher resolution and without the timecodes. In fact, the set of images without timecodes has less side cropping but more bottom cropping, removing the timecodes. Glossy prints provided by the Associated Press were not cropped in either direction.

  • Before V0.938: the page The Pentagon Strike stated: The idea that nearly all the remains of the 80-ton aircraft disappeared into the building is problematic because the punctured walls of the initial damage to the building do not include regions where the ends of the wings and the vertical tail section would have impacted. This ignores the fact that the ends of the wings and the vertical tail section are very light portions of the plane -- probably weighing less than 3 tons -- and if they were reduced to confetti, their remains could easily have been present in front of the building. See 911review.com's analysis of plane crash debris.

  • Before V0.944: the page Pentagon Attack Evidence stated: Despite an entry hole much smaller than the profile of a 757, there were virtually no remains of an 80-ton aircraft on the Pentagon's lawn. This statement greatly oversimplifies the facts. The punctures in the Pentagon's facade were large enough to easily allow the vast majority of a 757 to enter the building. See 911review.com's analysis of hole dimensions. As noted in the previous correction, the portions of a 757's profile that could not fit were very light and easily reduced to small confetti.

  • Before V0.983: the page Basement Bombs stated: The first [evidence of temperatures at the towers' foundations exceeding the melting point of steel] was the persistence of hot fires in the rubble piles for over 100 days after the attack. Then, when excavation reached the bedrock foundations, masses of once molten steel were discovered. We don't know of any source for the report of molten steel in the foundations other than Steve Tully and Mark Loizeaux, presidents of two of the companies granted contracts to remove the rubble.

  • Before V0.985: the page Building 7 stated: Building 7 was not hit by any aircraft, and was not significantly damaged by the violent destruction of either of the Twin Towers. This may understate damage to WTC 7 from the explosion of the North Tower. A photograph published by NIST in 2004 is the first we are aware of that shows any gouging of the building's exterior. It shows a gouge in WTC 7's southwest corner, apparently inflicted by rubble from the North Tower.

  • Before V0.989: the page The 1975 Fire stated: The fact that this fire covered six floors and burned for three hours suggests that it was more severe than the fire that occurred 80 floors above on September 11, 2001. Given the very sparse literature on the 1975 fire, the conclusion that it was more severe than the 2001 fire does not seem justified.

  • Before V0.996: the slide The Killer Fires Theory is Pure Fantasy stated: 1535ºC (2795ºF) - melting point of steel This is the melting point of iron, but not of steel, which is a mixture of iron and carbon whose melting point depends on its composition. Steel's melting point generally decreases with increasing carbon percentage. Most structural steel is is between 0.2 and 0.5 percent carbon by weight, and has a melting point above 1500ºC.

  • Before V0.9978: the page Official Pentagon Investigations stated: [The Purdue Study's] blaming of the majority of damage on the inertia of the fuel is starkly contradicted by the photographs taken soon after the crash, which show both unscarred limestone where the outer wings would have hit, and smashed-away portions of walls not in the path of the wings. This critique assumes that the wing fuel tanks extend to the outer portions of the wings. That is apparently not the case and, depending on how far out the tanks extend, the 90-foot expanse of breached walls on the first floor is arguably consistent with the "liquid hammer effect" of the fuel in the portions of the wings that did contain fuel.

  • Before V0.9991: the page The Attack stated: 9:38 AM: The Pentagon was hit in an assault involving a 757 jetliner. While we find that the evidence strongly supports that a jetliner or similar aircraft crashed at the Pentagon, we don't think that it conclusively shows that the aircraft was a 757, much less that it was Flight 77. On the other hand, we don't find any persuasive evidence that the jetliner was anything other than Flight 77. The mirky issue of what hit the Pentagon is the subject of this essay.

  • Before V0.9992: the page Squibs stated: In the terminology of demolition, 'squibs' are puffs or jets of smoke and dust that emerge from the facade of a building as demolition charges shatter the structure. Apparently this usage of the term 'squibs' was popularized after the attack. A search of literature not relating to the attack indicates a different meaning, typified by: "an electroexplosive device useful in igniting various explosive compositions in many different applications."

  • Before V1.008: the page 1 World Trade Center stated: In its final moments, the only easily visible fire was about 9 stories above the impact zone, where flames jutted out of a span about 40 feet wide. This understates the extent of fires visible in the North Tower prior to its destruction. This photograph, taken after the fall of the South Tower, shows fires extending over most of the expanse of the 98th floor near the windows of the northwest face. This photograph shows an area of fire on the 92nd floor.

  • Before V1.056: the page Other Aircraft contained a garbled excerpt from Skarlet's account, which, because it was taken out of context, incorrectly implied that Skarlet reported seeing a helicopter rather than a jetliner hit the Pentagon. In fact, Skarlet's full account is quite emphatic that a "huge jet" flew into the Pentagon.

  • Before V1.072: the page Pentagon Damage stated: The region with punctures on the first floor was no more than 90 feet wide. We have corrected this to state that the first-floor punctures extended for a width of at least 96 feet. This is because facade photographs clearly show that the punctures extended from column line 8 to 18. Assuming the columns were on 10-foot centers, this means the punctures extended for a width of about 100 feet. Moreover, two window bays appear to be punctured south of column line 18, adding another 20 feet to the width.

  • Before V1.076: two slides from the talk The 9/11/01 Attack on Manhattan: A Photographic Essay contained incorrect times and camera directions. These slides gave 9:10AM and 9:25AM as the estimated times, rather than times after 10AM.

  • Before V1.090: the page Missing Gold failed to note that the $200 million of gold attributed to the Bank of Nova Scotia may have been part of the the $220 million attributed to Comex clients, making the tally of $950 million questionable. Furthermore, the final paragraph stated: The circumstances surrounding part of the gold that was recovered offer clues to what may have happened to the unrecovered gold. According to reports, two truckloads of gold were found in a delivery tunnel under 5 World Trade Center in a 10-wheel lorry which had been crushed by falling steel. The vault was under 4 World Trade Center, which was closer to the South Tower, and more heavily damaged. There were no bodies discovered with the lorry, suggesting that whoever was removing the gold was warned of the imminent collapse of the South Tower. However, the page now notes that the report that the truck under WTC 5 was loaded with gold may have been based on erroneous readings of reports that crushed vehicles had to be removed to access the vaults under WTC 4.

  • Before V1.096: the page Pentagon Damage stated: The [C-Ring punch-out] hole, apparently made by an engine, is roughly in the position where the left engine would have passed. However, the engines would have much less energy than the lower half of the fuselage, with the landing gear, and the path of the fuselage seems to fit the lamp-pole path.

  • Before V1.096: the page Attack Plane Suffered Pre-Impact Damage stated: The physical evidence most problematic for the official account of Flight 77's crash are the photographs taken of the Pentagon's facade before and after the collapse of the overhanging section, showing areas of unscored limestone and intact windows where the wing tips and tail section would have hit, and column remnants where the right engine would have hit. The lack of large quantities of aircraft debris outside the building can be explained, if implausibly, by suggesting that the vast majority of debris entered through the impact punctures. There is a patch of missing limestone covering the projection of the left wing. The column remnants appear to be fallen sections of second-floor slab. It is not implausible that the vast majority of debris enered through the impact punctures.

  • Before V1.096: the page The Column Failure Theory is Inapplicable stated: Fires did not cover an entire floor in either tower. This is certainly true of the South Tower, since no photographs show evidence of fires on the northwestern half of the building at any time up to its total destruction. However, some photographs of the North Tower, show fires extending over almost an entire floor as seen from one face.

  • Before V1.109: the page General Myers stated: As Acting Chairman [of the Joint Chiefs of Staff], Myers was the highest-ranking military official, and the third in command, behind only the Secretary of Defense and the President. However, according to the JCS website the Joint Chiefs of Staff surves in an advisory role to the President and does not exercise command over armed forces.

  • Before V1.118: the page Distributed Explosives ennumerated several features that it suggested were inconsistent with the distributed explosives theory, including: Absence of shock waves, Melted appearance of columns, and North Tower fire augmentation after South Tower collapse. However, eyewitness accounts, such as the Oral Histories contain, indicate that there were strong shockwaves consistent with explosive detonations; the melted or draped appearance of column remains could also be explained by high blast pressures; and the North Tower's fire augmentation is difficult to quantify and could have resulted from the natural spread of the fires.

  • Before V1.140: the page The Twin Towers' Demolition stated: The core structures were virtually obliterated, leaving no pieces more than about 30 feet long. However, an aerial photograph published by NOAA shows a number of core column sections that are apparently about 60 to 70 feet long. In the portion of that photograph pictured here core column sections, which are long rectangular pieces, can be measured with reference to the perimeter wall sections, which are the clusters of narrow columns with perpendicular spandrel plates. The spandrel plates in a wall section are spaced on 12 foot centers.

  • Before V1.145: the page Towers' Design Parameters stated: According to Hyman Brown, a University of Colorado civil engineering professor and the World Trade Center's construction manager, 1 and 2 World Trade Center were designed to survive an impact and resulting fires from a collision by the largest commercial aircraft at the time, a Boeing 707-340. We have been unable to locate a credible source of this assertion. Hyman Brown was apparently not involved in the studies conducted in the design phase of the Towers that contemplated jetliner impacts.

  • Before V1.148: the page The June 1 Order stated: On June 1, 2001, S.A. Fry, Vice Admiral of the US Navy and Director of the Joint Staff, issued Chairman of the Joint Chiefs of Staff Instruction CJCSI 3610.01A [cached], apparently changing intercept procedures, perhaps profoundly. It required that all requests for assistance in hijackings be approved by the Secretary of Defense. However, CJCSI 3610.01A supersedes CJCSI 3610.01, dated July 31, 1997, which also states that such requests require approval by the Secretary of Defense.

  • Before V1.149: the page Thermobarics stated: A 'thermobaric' is a weapon that first disperses an aerosol mixture with a primary charge, and then ignites it with a secondary charge, causing a massive fireball and overpressures. Although this statement is true, the phrase "massive fireball" implies that any use of thermobaric devices would have produced bright colorful fireballs -- something conspicuously absent from visual records of the Towers' desruction. The page should have noted that the fireballs need not have been visible, since many fuel-air mixtures burn without emitting visible light. For example, hydrogen burns in air without a visible flame.

  • Before V1.178: the page Black Boxes stated: The black boxes of Flight 77 were allegedly found on September 14th, but yielded "nothing useful" according to FBI director Robert Mueller. Mueller's comment about finding "nothing useful" appears to have referred only to the cockpit voice recorder from Flight 77, and not the flight data recorder.

  • Before V1.185: the page Flight 77 stated: There was only one person on Flight 77 who allegedly called: Passenger Barbara Olsen supposedly placed two calls to her husband Ted Olsen. Flight attendant Renee A. May is also reported to have made a call.

  • Before V1.219: the page The Towers' History stated: Of the over 10,000 workers involved in building the complex, 62 died in construction accidents. The source cited for the figure of 62 fatalities, 'Facining Our Fascist State' does not provide a citation, and is apparently mistaken.

  • Before V1.235: The pages Forensic Metallurgy, Distributed Explosives, Evidence of Explosives, NIST's World Trade Center FAQ, and Reply to Protec's A CRITICAL ANALYSIS OF THE COLLAPSE OF WTC TOWERS 1, 2 & 7 FROM AN EXPLOSIVES AND CONVENTIONAL DEMOLITION INDUSTRY VIEWPOINT used the term intragranular in place of the correct term, intergranular, to describe observations about the melting of steel in structural members from the World Trade Center skyscrapers.

  • Before V1.237: The page Collapsing Buildings stated: It is interesting that, in spite of the thorough devastation of all the buildings with World Trade Center addresses, no buildings outside the blue zones were sufficiently damaged to warrant their demolition. However, there was a small building outside of this zone to be completely destroyed -- St. Nicholas's Church -- and the Deutche Bank Building was ultimately demolished floor-by-floor because its damage was deemed to great to rehabilitate.

  • Before V1.252: The page The Killer Fires Theory is Pure Fantasy (also here) stated: ~825º C (1517º F)- maximum temperature of hydrocarbon fires burning in the atmosphere without pressurization or pre-heating (premixed fuel and air - blue flame) This ignores the role of ambient heat in elevating fire temperatures. The 825º C figure was based on a measurement of the temperature of a blue flame from a gas-stove -- an example of an air-aspirated hydrocarbon-fueld fire with pre-mixed fuel and air. Since the flame was in room-temperature surroundings, the experiment essentially measured the increase in temperature attributable to that type of fire, rather than any kind of maximum temperature.

  • Before V1.253: The page The Fires: The Twin Towers' Fires and Their Possible Effects stated: 800° C is near the maximum flame temperature of hydrocarbons burning in air without pre-heating or pressurization of the air. Even those temperatures are usually reached only with premixed (blue) flames, such as in gas stoves and blowtorches. Diffuse flames, of the type in the WTC, tend to be far cooler. In fact, flame temperatures of even diffuse, turbulent air-aspirated hydrocarbon-fueled flames can be much higher than 800°C. The physics of flame temperatures is a complex subject, and is, perhaps, less relevant to the understanding of effects of the fires in the Twin Towers than are historical data and simulations on the nature of building fires.
    The page further stated: In order to soften columns, fires would have to exceed the capacity of the 100,000 tons of steel in each building to draw away the heat. This implies that the total mass of steel in a Tower was particularly relevant to the heat wicking ability of the steel frame in the fire zone. Given the distances of the crash zones from the more heavily built lower stories of the Towers, and the steel's coefficient of thermal conductivity, most of the steel may have had a relatively small contribution to the transfer of heat away from the fires.

  • Before V1.259: The page Passenger Lists: Victims Lists, Passenger Manifests, and the Alleged Hijackers, referring to a set of fax reproductions, stated: Low-quality reproductions of alleged passenger manifests were released on a website of Moussaoui trial exhibits in July of 2006. However, the faxes do not appear to be in the voluminous Moussaoui trial exhibits, although they surfaced at about the same time as the trial exhibits were published. Instead, they were obtained by author Terry McDermott from the FBI in the course of preparing his book Perfect Soldiers.

  • Before V1.309: The page Explosive Detonation, referring to the crash-and-explosion at the Pentagon, stated: These characteristics cannot be explained by the rapid combustion of jet fuel. Even if it is true that jet fuel combustion alone could not account for these reported characteristics, it is conceivable that other effects of the high-speed crash would.
  • Before V1.309: The page Pentagon Explosion, stated: The Pentagon attack involved an explosive detonation. This conclusion seems open to question, given a closer look at the physics of such a crash.
  • Before V1.42: The page Other Aircraft, attributed the quote beginning with: He said that he saw a helicopter circle the building. was attributed to Lincoln Leibner. In fact, the quote was from the CNN reporter Chris Plante, who was describing an account of an un-identified military officer.

page last modified: 2014-11-02