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3C. From this video of WTC1 stop it two seconds after failure (at 33sec). The plumes on the right side are about 60 feet from the building. Stop the video two seconds later (at 35 sec). The plumes are about 120 feet from the building.
http://www.youtube.com/watch?v=ZVDaAufKnLc
3D David Chandler calculates that at this failed floor WTC1 (96th floor), the explosive velocity of the columns propelled 600 feet horizontally onto the Winter Garden would be about 50 mph. At two seconds after failure, this would put the exploded columns at 73 fps x 2 seconds = 146 feet away from the building, outpacing the dust plume (60 feet) and should have been visible in the video.
http://www.youtube.com/watch?v=aUKLOlIhang
At four seconds after failure, this would put the exploded columns at 73 fps x 4 seconds = 292 feet away from the building, outpacing the dust plume (120 feet) and should have been visible in videos.
3E. But since the expelled columns ahead of the dust plume are not visible, the columns could not have reached 600 feet by the use of large explosive charges in the ceiling plenum, or elsewhere for that matter,
they reached 600 feet by toppling, David Chandler and the CTs are wrong.
http://www.youtube.com/watch?v=ESaIEVxLnK4
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