Free-fall speed is the rate in which an object falls when it encounters zero resistance, as would be the case if all of a buildings core columns were taken out by a controlled demolition. A simple review of the videos from that day, however, show that neither of the towers fell at that speed. The following video does a great job showing the fallacy of "free fall speed" theory:
As you can see both buildings fall considerably slower than the claims by conspiracy theorists that they fell at free fall speed (9 seconds). You can watch any video of the collapse and time it for yourself.
A simple review of the raw evidence makes it clear that the claims that the towers fell at free fall speed are simply erroneous While that is not proof that 9/11 was not a conspiracy, it simply eliminates that as evidence of a government plot.
World Trade Center, New York, aerial view March 2001. (Photo credit: Wikipedia)
