Posted by
techlizard on Wednesday, July 12, 2006 11:52:09 PM
With conspiracy nuts like
Kevin Barrett spouting paranoid theories about 9-11 -- not only on TV and the internet, but even in publicly funded college classrooms, it may be time for a bit of a reality check. The most common claim is that jet fuel won't burn hot enough to melt steel, so the towers must have been brought down by a controlled demoltion. Yes, it sounds crazy, but people actually believe this stuff.
Of course, this claim is easily debunked by anyone with a few basic facts. From last year's awesome conspiracy-debunking article by Popular Mechanics:
FACT: Jet fuel burns at 800° to 1500°F,
not hot enough to melt steel (2750°F). However, experts agree that for
the towers to collapse, their steel frames didn't need to melt, they
just had to lose some of their structural strength--and that required
exposure to much less heat. "I have never seen melted steel in a
building fire," says retired New York deputy fire chief Vincent Dunn,
author of The Collapse Of Burning Buildings: A Guide To Fireground
Safety. "But I've seen a lot of twisted, warped, bent and sagging
steel. What happens is that the steel tries to expand at both ends, but
when it can no longer expand, it sags and the surrounding concrete
cracks."
"Steel loses about 50 percent of its strength at 1100°F," notes senior
engineer Farid Alfawak-hiri of the American Institute of Steel
Construction. "And at 1800° it is probably at less than 10 percent."
NIST also believes that a great deal of the spray-on fireproofing
insulation was likely knocked off the steel beams that were in the path
of the crashing jets, leaving the metal more vulnerable to the heat.
But
jet fuel wasn't the only thing burning, notes Forman Williams, a
professor of engineering at the University of California, San Diego,
and one of seven structural engineers and fire experts that PM
consulted. He says that while the jet fuel was the catalyst for the WTC
fires, the resulting inferno was intensified by the combustible
material inside the buildings, including rugs, curtains, furniture and
paper. NIST reports that pockets of fire hit 1832°F.
"The jet fuel was the ignition source," Williams tells PM. "It burned
for maybe 10 minutes, and [the towers] were still standing in 10
minutes. It was the rest of the stuff burning afterward that was
responsible for the heat transfer that eventually brought them down."
There's
much more at the Popular Mechanics web site. None of this is opinion, just cold, hard facts -- and just as certain as any other set of "proven" facts. The conspiracy nuts simply ignore any evidence that contradicts their whacky ideas, which is why the above conspiracy claim is still the one you're most likely to hear, despite the fact that it has been
proven false (as have most of the other claims).
Question: Should Barett be allowed to teach what has been proven false at a public university? What's next: holocaust denial? there was no moon landing? the Earth is flat?