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Background Attack Aftermath Evidence Misinformation Analysis Memorial

Pentagon Damage

Damage to Pentagon and Surroundings Prompts Questions About Attack Plane

Skeptics of the account that Flight 77 crashed into the Pentagon have maintained that the pattern of damage to the Pentagon and its surroundings is not consistent with the impact of a Boeing 757. They have advanced the following arguments against the crash of a Boeing 757:

  • The central impact hole has a diameter only slightly larger than a 757 fuselage.
  • The damage on the right side of the central hole is difficult to reconcile with the impact of an intact starboard engine of a 757.
  • The single hole through the C-Ring of the building suggests a single-engine attack plane.
  • The lawn outside the damaged facade shows no signs of gouging in the limited number of photographs.
  • Objects seemingly in the plane's flightpath outside the building were apparently not disturbed.
  • The facade shows no impression of the ends of the wings or vertical stabilizer of a 757.
On closer examination, many of these arguments are not as convincing as they might seem. Several are based on errors in interpreting the evidence, as outlined in the Pentagon Attack Errors section of 911review.com. The final argument, about the lack of impressions of the plane's extremities, is more difficult to dismiss, and we examine it in some detail.

Misleading graphic: French researcher SilentButDeadly created this simulation showing a 757-200 on Flight 77's alleged impact trajectory into the Pentagon, where multiple images of the post-impact damage were used to create the photomontage of the damaged facade. [full image] Since the image superimposes photographs taken from different vantage-points, it greatly distorts the positions of objects relative to the building, such as the spools. It also gives the impression, if only subconsciously, that the jetliner is a solid stainless steel object. In fact, jetliners are very light and fragile compared to buildings: they consist mostly of aluminum and have skin less than 2mm thick.

Damage to the Facade

The extent of damage to the Pentagon's west wall is not fully visible in any one photograph. However, a complete picture of the damage was obtained by compositing a number of photographs taken after the crash but before the overhanging section collapsed about 30 minutes later.

The Entry Punctures

Regions in which the Pentagon's west facade were punctured were restricted to the first and second floors. The puncture on the second floor was about 18 feet wide and extended to the top of the second floor, about 26 feet above the ground. The region with punctures on the first floor was about 96 feet wide.

Damage Beyond Punctured Region

Beyond the 90-foot-by-26-foot region within which walls were broken away, the facade showed abrasion suggesting blast damage, but no impression of the profile of a Boeing 757. No windows were broken on either side of the 90-foot span or above the second floor.

A visual comparison of the damage to the Pentagon and the Twin Towers suggests a problem with the absence of impressions on the Pentagon's facade of the wings or vertical tail section. However, there are some limitations to this comparison.

First, while the impact impressions in the towers extended to the ends of the wings, the steel columns were not severed by outermost portions of the wings. Rather the thin aluminum cladding was scored. Second, the curtain walls of the towers are hardly comparable to the heavy masonry walls of the Pentagon. While it can be argued whether the towers' walls were stronger, the mass of the walls is a very important factor in such a high-speed collision.

Despite uncertainties regarding the construction and reinforcement of the Pentagon's facade, it does seem peculiar that there is intact facing (limestone?) in areas where the wings and tail apparently would have impacted. If the impact speed was over 400 mph, as the ACSE report suggests, it would seem reasonable to assume that the wings and tail could have folded back and thereby avoided impacting those areas.

The lack of impressions of the plane's extremities is perhaps the strongest single piece of evidence adduced by supporters of no-Boeing theories. However, this is not evidence that no 757 crashed at the Pentagon. Rather it is evidence that no intact 757 crashed into the Pentagon's facade. If the extremities of a 757 were shredded just before impact, they would have failed to make impressions in the facade. A similar scenario is explored by French researcher Eric Bart, who suggests that explosives in the plane's fuselage just prior to impact caused the wings to rotate and impact the facade in a trajectory different from that expected in a simple crash. Bart's theory also accounts for elements of eyewitness accounts not explained by the simple 757 crash described by the official story.

This image shows the largest of several exit punctures in the inward-facing first-story wall of the Pentagon's C-Ring. Aircraft debris is visible near the hole. [full image]

The C-Ring Exit Hole

The wall of the Pentagon's C-Ring was punctured by a nearly circular hole. The hole was apparently made by the remains of the plane's fuselage, whose apparent impact trajectory lines up with the punch-out hole.

Many researchers have asserted that whatever produced the C-Ring hole had to pass through six masonry walls, since it had to traverse three rings -- C, D, and E. However the exterior walls between the outermost three rings did not go down to ground level, since the intervening light-wells were only three stories deep. The outer three rings were unified on the first and second floors, meaning that the only heavy structures between the facade and the C-Ring wall with the hole were occasional columns. Thus it is plausible that an engine could have passed through the three rings, missing the reinforced concrete pillars, and puncturing the C-Ring wall.


Damage to the Surroundings

Many reports held that the jetliner hit the ground short of the building's wall and that the ground absorbed much of the plane's kinetic energy. If that were true it might help to explain the damage to the building being much more limited than expected. But such accounts seem to be contradicted by photographs showing an apparently undisturbed lawn with undisturbed objects close to the wall.

Deceptive Appearances

The conclusion that the lawn was ungouged and that objects remained standing close to the point of impact seems inescapable on the basis of post-crash photographs. However, most such photographs were taken from the highway at least 500 feet from the building, resulting in apparent distances near the building being highly foreshortened. In the photograph below, the upright spool nearest the building is actually about 30 feet from it. The cluster of spools to the left is at least 80 feet from the facade. The fence in the right portion of the photograph is about 100 feet from the facade.

page last modified: 2013-03-21