Why wasn't the hole as wide as a 's nearly foot wingspan? A crashing jet doesn't punch a cartoon-like outline of itself into a reinforced concrete building , says ASCE team member Mete Sozen, a professor of structural engineering at Purdue University. In this case, one wing hit the ground; the other was sheared off by the force of the impact with the Pentagon's load-bearing columns, explains Sozen, who specializes in the behavior of concrete buildings.
What was left of the plane flowed into the structure in a state closer to a liquid than a solid mass. The tidy hole in Ring C was 12 feet wide—not 16 feet. ASCE concludes it was made by the jet's landing gear, not by the fuselage. FACT: Some windows near the impact area did indeed survive the crash.
But that's what the windows were supposed to do—they're blast-resistant. Some were knocked out of the walls by the crash and the outer ring's later collapse.
Kilsheimer was the first structural engineer to arrive at the Pentagon after the crash and helped coordinate the emergency response.
I picked up parts of the plane with the airline markings on them. I held in my hand the tail section of the plane, and I found the black box. Construction of the Pentagon began, ironically enough, on September 11, Wartime urgency meant that the Pentagon was completed in record time—just 16 months using 15, construction workers. When the Pentagon was built, no one knew that it would become an iconic monument to U.
In fact, the architects thought it would be abandoned after the war and turned into a massive record storage depot. Their prediction was wrong, but fortuitous. Thinking the Pentagon would need to store heavy caches of records for the long haul, the U. C four days before the terrorist attack. In fact, it was a full 30 minutes before a portion of the building directly above the crash site collapsed, allowing more than enough time for survivors to escape.
Incredibly, not one Pentagon worker was killed during the partial collapse of the second through fifth floors.
In an incredible stroke of luck, that wedge had recently undergone a major renovation and only a fraction of the workers had moved back into their offices. If the plane had hit any other section of the building that day, there could have been as many as 4, Pentagon employees in the flight path.
The Boeing weighed an estimated Flight 77 took off from Washington D. Most of that fuel was still unspent when the jetliner struck the Pentagon.
What Dusenberry and his colleagues were there to figure out was how the second floor of the Pentagon remained standing after dozens of first-floor columns were destroyed or severely damaged. The upper sections only collapsed after sustaining severe damage from a raging fire.
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