On 3 Mar 2006 12:55:44 -0800, wrote:
wrote:
I would like to give you my input as to the events on September 11, and
why it is a physically provable fact that all of the damage done to the
Pentagon could not have occurred solely from a Boeing 757 impact,

oh, this will be good.

[...]

We are lead to believe that not only did the 757 penetrate the outer
wall, but continued on to penetrate separate internal walls totaling 9
feet of reinforced concrete. The final breach of concrete was a nearly
perfectly cut circular hole in a reinforced concrete wall, with no
subsequent damage to the rest of the wall. If we are to believe that
some how this aluminum aircraft did in fact reach this final wall. It
is physically impossible for the wall to have failed in a neat clean
cut circle, period. When I first saw this hole, a chill went down my spine

Sorry, but this is just not so. "neat clean" was a feature of the
nature of impact. By the time the mass was reaching those last
walls, velocity was lower, but it was almost assuredly concentrated
in a narrow channell.

see pictures: http://images.google.com/images?q=pentagon%20hole

because I knew it was not possible to have a reinforced concrete wall
fail in this manner, it should have caved in, in some fashion.

Sorry, the reinforcing frequently supports the otherwise heavily
cracked (or crazed really) concrete. In this case I suspect there was
some block involved although I'm not sure. That even tends to
concentrate the area even more.

The Pentagon's exterior walls are not reinforced concrete. The building
does have reinforced concrete columns and floor slabs, but the wall between
the columns (which are spaced about 10 feet apart on the first floor) is
8 inches of brick infill with a 5-inch limestone facing over the brick.
See the Pentagon Building Performance Report [1] for details of the
construction.


ljd

[1] http://fire.nist.gov/bfrlpubs/build03/art017.html