The American Society of Civil Engineers (ASCE) studies the crash of Flight 77 into the Pentagon and the building’s architectural response to the impact, blast, and subsequent fires. [American Society of Civil Engineers, 1/17/2003] The six-member Pentagon Building Performance Study team is headed by Lead Technical Director Paul F. Mlakar, and also includes Mete A. Sozen. Mlakar and Sozen had previously worked together on the Federal Emergency Management Agency (FEMA) investigation into the Oklahoma City bombing under W. Gene Corley, who is now assigned as FEMA/ASCE’s team leader for the World Trade Center investigation (see September 12, 2001). [Corley et al., 10/1997; Mlakar et al., 1/2003, pp. i 
] Some aspects of the Oklahoma City investigation were controversial. [Guardian, 5/5/2001] Sozen is also tasked with “project conception” for Purdue University’s computer simulation of the Pentagon attack, images from which are also used in the Performance Report, when it is issued later (see January 23, 2003). [Purdue University Department of Computer Science, 9/11/2002] The Building Performance Study team only inspects the Pentagon on two occasions. Team leader Mlakar is granted “limited access” to the site for a week from September 14-21, and on October 4, “controlled access” is granted to the full team, which meets with Corley and inspects the site “for approximately four hours.” All airplane debris has been removed by this time, as well as most of the loose debris from the impact and collapse. Along with interviews and technical information provided by the Pentagon Renovation Project, the photos and data gleaned on these visits are the basis of the team’s analysis of the building’s response to the impact of Flight 77. The study is completed in April 2002, though the report will not be released for another nine months. [Mlakar et al., 1/2003, pp. 1, 18 ]
September 15, 2001 and After: Various Explanations Offered for Pentagon ‘Exit Hole’
Various explanations are offered for the “exit hole” that appeared in an internal wall in the Pentagon following the attack on 9/11 (see May 3, 2002): 
As the hole is near the end of the plane’s trajectory through the building, it is suggested it was made by a piece of the plane. Pentagon Renovation Program spokesman Lee Evey explains on September 15, “the nose of the plane just barely broke through the inside of the C Ring, so it was extending into A-E Drive a little bit.” [US Department of Defense, 9/15/2001] Eleven days later, another military source claims that an engine of the plane was responsible for creating the hole. [MDW News Service, 9/26/2001] Photos, video, and some eyewitness accounts agree on landing gear elements at or near the hole, indicating one of the three sets of landing gear may have been responsible. Sergeant First Class Reginald Powell recalls seeing “a big 8 by 10… hole in the wall. You could see the tire, the landing gear, were just forward of it.” [Marble and Milhiser, 9/2004, pp. 118] The book Debunking 9/11 Myths by Popular Mechanics magazine will say in 2006 that the density of the landing gear means it was “responsible for puncturing the wall in Ring C.” The book cites Air Force Surgeon General Paul Carlton Jr. and Paul Mlakar, lead author of the American Society of Civil Engineers’ (ASCE) Pentagon Building Performance Report, who says “he saw the landing gear with his own eyes.” [Dunbar and Reagan, 2006, pp. 70] A wheel hub is found outside the hole in the A-E Drive service roadway and photographed there. [Jeff Scott and Joe Yoon, 1/21/2007] Another theory put forth in a 2004 National Geographic program is that reverberating shockwaves from the plane’s impact were responsible for the hole. [National Geographic Channel, 2004] Shortly after the attack, rescue workers reportedly “punched a hole” somewhere in the Pentagon “to clean it out,” although there are no sources that say that this was the reason for the hole to the A-E Drive. [US Department of Defense, 9/15/2001] Some accounts refer to the hole as a ‘punch out’ hole, due to the words “punch out” spray painted near it after 9/11. [Mlakar et al., 1/2003, pp. 30 ] However, punch out appears to be a construction term referring to a list of problems to be corrected. In this case it may be a call for assessment of the damage inside. [Home Building Manual, 8/25/2007] French author Thierry Meyssan claims that the unusual nature and shape of the hole indicates it was made by a missile, not an airliner (see Early March 2002). [Meyssan, 2002, pp. 55-63] The 2008 book Firefight: Inside the Battle to Save the Pentagon on 9/11, by Patrick Creed and Rick Newman, will offer a description of the hole and how it was created that is strikingly similar to Meyssan’s earlier observations but without questioning the official account that Flight 77 crashed into the building. In its photo-insert, the book shows a photograph of the exit hole and comments: “The ‘punch-out’ hole blown into a wall where Flight 77 finally came to rest. The hole was created by explosive energy; the plane’s soft aluminum nose and fuselage crumpled the instant it struck the building.” The book also says in its description of the crash, “The 182,000-pound aircraft was morphing into an enormous mass of energy and matter, plowing forward like a horizontal volcanic eruption.” It continues, “As the mass traveled through the building, it began to resemble a shaped charge, a form of explosive that funnels its force into a small, directed area—like a beam of energy—in order to punch holes through armor or other strong material.” [Creed and Newman, 2008, pp. 27]
In addition, the ASCE team’s photo of the hole, and its assessment of the damaged support columns nearest to it, are provided by the FBI, suggesting the bureau has special jurisdiction at the exit hole. [Mlakar et al., 1/2003, pp. 30 ]
