Further, the broken windows and detached marble panels in the lobby and witness accounts of explosions first occurring in the basements were attributed to “torque forces” from aircraft strikes above the 92nd floor in No. 1 and the 78th floor in No. 2.
As to molten metal that reportedly burned for weeks under the sites of No. 1 and 7, the cause was said to be the WTC’s still-operational continuous battery systems.
(6) That NIST panelists admitted in their 10,000-page WTC report (October 2007) the free-fall vertical collapses of the Towers——by symmetrical progression——in less than 11 seconds just outside their footprints, was “inexplicable.”
Their most important conclusion was that though the Tower fires were fed by building furnishings, these oxygen-starved, jet-fueled fires never exceeded 500ºF. Steel only begins to soften at 1,000ºF and melts at 1,500ºF, they noted.
They also ruled out “pancaking” because resistance met by floors below would have added considerable time to actual collapse durations: 110 seconds minimum.
the collapses were attributable either to missiles or bomb-laden military aircraft, not commercial airliners. This theory challenges the evidence of on-site witnesses, passenger lists and the victims’ family and friends. Yet Air Force and Air Force Academy sources have speculated that the planes could have been E-10s.
Aircraft designers, pilots and civil aviation examiners also are aware that any jet aircraft could be taken over remotely. For example, the Global Hawk remote-control system is frequently cited in the literature concerning the Department of Defense’s weaponry.
But after the air attack on the North Tower, some spectators said a plane struck the South Tower. Minute examination of the photographic and videographic evidence has suggested the possibility of a pod in the undercarriage of a plane that could have contained high-yield explosives.
(8) That when steel (not concrete) buildings are impacted by aircraft, destroying several columns and beams——as demonstrated in 1945 when a B-25D struck the Empire State Building——the stress is “redistributed.” Remaining columns become a “truss network to bridge over the missing columns.” The Towers’ head structural engineer, John Skillings, noted that they were designed to withstand the same kinetic energy whether expended by a Boeing 707 or a 767.
As to heat dissolving steel beams and columns, even fires involving 10,000 gallons of jet fuel——combined with office materials——none exceeded 500ºF, far too low to have any impact on those structures. If they had had impact, structural experts have posited that the collapses would have been gradual, in less than 10 seconds, because the beams and columns would not have gradually relinquished their structural strength.
Jet-fuel fires are typically brief, and 9/11 photographs and video footage reveal that significant amounts of that fuel burned outside the buildings. But inside the buildings, the same visual evidence exhibits the characteristic of an oxygen-starved blaze; black smoke indicates an oxygen-deprived fire.
In addition, Newton’s Law of Conservation of Momentum——collapsing floors meeting the resistance of 100,000 tons in remaining floors——would have decreased the rate of descent significantly.
If “pancaking” had occurred, Newton’s Law application would mean that the Towers’ 110 floors would have had to collapse within one minute and fifty seconds. (No. 1: 11 seconds; No. 2: 9 seconds; both at nearly free-fall speed.)
Contrary to theories that floor collapses created compressed air responsible for plumes and squibs, this theory contends that compression lacked the force to propel 50-ton columns and 20-ton beams 300-400 feet to be embedded in nearby buildings.
Photographic evidence of interior damage at the neighboring Deutsche Bank building’s 15th floor reveals that beams and columns flung from the South Tower had an upward, not lateral, trajectory that opened a 20-floor gash; that trajectory suggests the beams and columns had been ejected from the South Tower’s basement or lower floors. The same explanation may account for exterior damage to Building 7 from the North Tower.
With regard to claims that continuous batteries furnished heat for the reportedly long-lasting molten stage of metal, none was found under Buildings 3, 4, 5, and 6 which also relied on that emergency power source. By contrast, both molten metal as well as dust clouds are recognized as byproducts of explosives. Though heavily damaged from fire and debris, none of those four structures dissolved into dust.