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, and
therefore the 9/11 Commission report is not complete and arguably a
cover up. I will not speculate about what may have been covered up, I
will only speak from my professional opinion.

I am a Mechanical Engineer who spent many years in Aerospace, including
structural design, and in the design, and use of shaped charge
explosives (like those that would be used in missile warheads).

The structural design of a large aircraft like a 757 is based around
handling the structural loads of a pressurized vessel, the cabin, to
near atmospheric conditions while at the lower pressure of cruising
altitudes, and to handle the structural and aerodynamic loads of the
wings, control surfaces, and the fuel load. It is made as light as
possible, and is certainly not made to handle impact loads of any kind.

If a 757 were to strike a reinforced concrete wall, the energy from the
speed and weight of the aircraft will be transferred, in part into the
wall, and to the structural failure of the aircraft. It is not too far
of an analogy as if you had an empty aluminum can, traveling at high
speed hitting a reinforced concrete wall. The aluminum can would
crumple (the proper engineering term is buckle) and, depending on the
structural integrity of the wall, crack, crumble or fail completely.
The wall failure would not be a neat little hole, as the energy of the
impact would be spread throughout the wall by the reinforcing steel.

This is difficult to model accurately, as any high speed, high energy,
impact of a complex structure like an aircraft, into a discontinuous
wall with windows etc is difficult. What is known is that nearly all of
the energy from this event would be dissipated in the initial impact,
and subsequent buckling of the aircraft.

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

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.

How do you create a nice clean hole in a reinforced concrete wall? with
an explosive shape charge. An explosive shape charge, or cutting charge
is used in various military warhead devices. You design the geometry of
the explosive charge so that you create a focused line of energy. You
essentially focus nearly all of the explosive energy in what is
referred
to as a jet. You use this jet to cut and penetrate armor on a tank, or
the walls of a bunker. The signature is clear and unmistakable. In a
missile, the explosive charge is circular to allow the payload behind
the initial shape charge to enter what ever has been penetrated.

I do not know what happened on 911, I do not know how politics works in
this country, I can not explain why the main stream media does not
report on the problems with the 911 Commission. But I am an engineer,
and I know what happens in high speed impacts, and how shaped charges
are used to "cut" through materials.

I have not addressed several other major gaps in the Pentagon/757
incident. The fact that this aircraft somehow ripped several light
towers clean out of the ground without any damage to the aircraft
(which
I also feel is impossible,) the fact that the two main engines were
never recovered from the wreckage, and the fact that our government has
direct video coverage of the flight path, and impact, from at least a
gas station and hotel, which they have refused to release.

You can call me a tin hat, crazy, conspiracy theory, etc, but I can say
from my expertise that the damage at the Pentagon was not caused solely
by a 757.


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u2r2h speculation:

The shaped charge was between the tree and the wall.
It was timed to conincide with the impact.
Its task was to kill the engineers inside who were
running the show... killing witnesses.
if you don't believe, check the job descriptions
of the victims inside.