New simulation shows 9/11 Pentagon plane crash with scientific detail

Listen up, Sheepdog.

For "where's the evidence?" conspiracy buffs:

New simulation shows 9/11 Pentagon plane crash with scientific detail

WEST LAFAYETTE, Ind. – Engineers, computer scientists and graphics
technology experts at Purdue University have created the first
publicly available simulation that uses scientific principles to
study in detail what theoretically happened when the Boeing 757
crashed into the Pentagon last Sept. 11.

Researchers said the simulation could be used as a tool for designing
critical buildings – such as hospitals and fire stations – to
withstand terrorist attacks.

The simulation merges a realistic-looking visualization of the
airliner approaching the building with a technical, science-based
animation of the plane crashing into the structure.

"This is going to be a tremendous asset," said Mete Sozen, Purdue's
Kettelhut Distinguished Professor of Structural Engineering.
"Eventually, I hope this will be expanded into a model that we can
use to help design structures to resist severe impact loads.

"Using this simulation I can do the so-called 'what-if' study,
testing hypothetical scenarios before actually building a structure."

The simulation can be recorded on a DVD and played on an ordinary
personal computer.

The software tool is unusual because it uses principles of physics to
simulate how a plane's huge mass of fuel and cargo impacts a
building. The plane's structure caused relatively little damage, and
the explosion and fire that resulted from the crash also are not
likely to have been dominant factors in the disaster, Sozen said.

The model indicates the most critical effects were from the mass
moving at high velocity.

"At that speed, the plane itself is like a sausage skin," Sozen said.
"It doesn't have much strength and virtually crumbles on impact."

But the combined mass of everything inside the plane – particularly
the large amount of fuel onboard – can be likened to a huge river
crashing into the building.

The simulation deals specifically with steel-reinforced concrete
buildings, as opposed to skyscrapers like the World Trade Center's
twin towers, in which structural steel provided the required strength
and stiffness. Reinforced concrete is inherently fire resistant,
unlike structural steel, which is vulnerable to fire and must undergo
special fireproofing.

"Because the structural skeleton of the Pentagon had a high level of
toughness, it was able to absorb much of the kinetic energy from the
impact," said Christoph M. Hoffmann, a professor in the Department of
Computer Sciences and at Purdue's Computing Research Institute.

Sozen created a mathematical model of reinforced concrete columns.
The model was then used as a starting point to produce the
simulation.

Continued at: http://news.uns.purdue.edu/hp/Sozen.Pentagon.html

Watch the simulations here:
http://www.cs.purdue.edu/homes/cmh/simulation/