Discussion Page for:

John D. Wyndham

Bringing Closure to the 9/11 Pentagon Debate

First Published: Foreign Policy Journal, October 2016, Version 1

View Author Details for: Wyndham

Discussion for Version 1, October 2016

Comment 1: - By: Robin Hordon, Former FAA Air Traffic Controller - Received 12/16/16 - Posted: 04/16/17

[Moderator Note: The following statement by Robin Hordon, former Federal Aviation Administration (FAA) Air Traffic Controller, was preceded and followed by a number of points of concern regarding the 9/11 Pentagon event. These points included ones that questioned the authenticity and interpretation of the FDR data, whether light pole #2 was knocked down by the plane or by some other means, and whether or not there was a Pentagon event at an earlier time than 09:37:46 which is the official event time.]

"Please note while referring to above noted points about the USAF operating both B757 and B767 aircraft in their fleet, it's not that complicated to paint one of the USAF aircraft to reflect AAL's paint scheme. This is why my slightly revised position about the Pentagon attack is that:"

"A twin under-wing turbojet engine low wing aircraft painted in American Airlines' color, which was the size of an airliner...and after passing atop the Naval Annex, then impacted the VADOT sign support removing a step rung...then cut off and ingested the top of a tree at the edge of Hwy 27 with its left engine...then its wings impacted at least three light poles all nearer the Pentagon...and then just before Pentagon impact, the aircraft impacted both a low wall near the Pentagon with the left engine...and impacted, in two places, a generator located close to and at the side of the Pentagon. The two impact locations on the generator are: the top left corner with the aircraft's right engine...and the top-middle surface of the generator with what could be the wing's flap track nearest the right engine...with all of the above happening just before the aircraft impacted the Pentagon at and below the second floor cement slab...and all the while the aircraft was in a slight left bank from at least the generator into the Pentagon."

"So, I think that with more research I will be able to support more of your positions."

Comment 2: - By: John D. Wyndham - Posted: 04/20/17

Response from Scientific Method 9/11 to Robin Hordon's comment of 12/16/16

Thank you for your comments.

Your statement above already supports the bulk of our position, namely, that a large plane, matching the description and dimensions of an American Airlines Boeing 757, struck the Pentagon on 9/11 [1,2]. Some of your many other points and details will require further research before a response is made. However, we will begin the discussion with your “revised position” statement above.

The physical evidence for the plane’s dimensions comes from photographs of the downed light poles, and the impacts at the low wall and generator trailer. This physical evidence is supported by eyewitness’ accounts of the plane striking the light poles, and the plane engines striking the low wall and generator. The plane type is supported by witness observations of the size, markings and shape of the aircraft.

The physical separation of the low concrete wall and the top left or north corner of the generator was about 43 feet, matching the engine separation of a Boeing 757 which is 42.5 feet. The plane struck five light poles whose position and separation on each side of the plane path indicates a wingspan of at least 100 feet. The locations of other nearby poles which were not struck indicate a wingspan not more than 130 feet. The actual wingspan of a Boeing 757 is within this range at about 125 feet. The separation of the struck portion of the generator and the gouge from the first flap canoe is approximately 6 to 10 feet, which also matches the geometry of a Boeing 757 (approximately 9.7 feet horizontal distance from center of engine to first flap canoe).

The vast majority of eyewitnesses who saw the plane, including 62 or more who saw the plane impact the west wall of the Pentagon, described the plane as a large one. Many witnesses noticed the markings on the plane and tail as being those of an American Airlines plane. A number of witnesses stated it was Boeing 757, 737, 767 or 707. One expert eyewitness, an airlines pilot, Tim Timmerman, stated that the plane was an American Airways 757.

The plane’s path is well-defined by eyewitnesses, the radar data, and the properly-decoded FDR data which was analyzed by Warren Stutt and Frank Legge [3, 4]. Your concerns about the FDR data are noted here, but we cannot respond to them at this time. The plane did not pass “atop the Naval Annex” but flew close to the south-east corner of the building between Columbia Pike and Highway 395. We are in agreement that the plane’s wingtip most probably removed a step rung from a VDOT pole., and it was the right wingtip that did this damage. However it was the right engine, not the left engine which clipped and ingested the branches from the top of a tree near Highway 27. This is ascertained from the location of the clipped tree and the plane path as determined, for example, by the downed light poles. Branches ingested by the right engine can explain the smoke trail from the right engine from that point on, as seen in the security camera videos. The plane impacted five light poles; your concern about the second light pole is noted, but will be addressed through further analysis. We agree with your statements about the low wall and generator impacts, the plane’s nose hitting just below the second floor slab, and the plane’s tilt to the left upon impact.

There is no credible evidence for an event time earlier than 09:37:46. This issue has been thoroughly dealt with in other papers [5,6].

We are encouraged by the substantial amount of agreement now existing between your analysis and our own. Further research is needed to respond to and resolve some of your other points. However, in our opinion, these resolutions will not change the conclusion of large plane impact at the Pentagon on 9/11, an issue that has been the subject of vigorous debate since September 11, 2001.


[1] John D. Wyndham, "Bringing Closure to the 9/11 Pentagon Debate," October, 2016.

[2] Ken Jenkins (video) and David Chandler (talk), Video: "The Pentagon Plane Puzzle." Talk: "Going Beyond Speculation: A Scientific Look at the Pentagon Evidence." August, 2016. First published November, 2015.

[3] Frank Legge, "The 9/11 Attack on the Pentagon: the Search for Consensus," June, 2012.

[4] Frank Legge and Warren Stutt, "Flight AA77 on 9/11: New FDR Analysis Supports the Official Flight Path...," January, 2011.

[5] Victoria Ashley, David Chandler, Jonathan H. Cole, Jim Hoffman, Ken Jenkins, Frank Legge, and John D. Wyndham, "The Pentagon Event: The Honegger Hypothesis Refuted," April, 2016.

[6] John D. Wyndham, "The Pentagon Attack: The Event Time Revisited," March, 2013.

For additional papers on this subject, see the Pentagon sections at Scientific Method 9/11 and Scientists for 9/11 Truth.

Comment 3: - By: Sami Yli-Karjanmaa - Received 10/19/16 - Posted: 05/16/17

"I very much appreciate your effort to apply the scientific method in the Pentagon case. Theories that do not explain our observations must be rejected."

"[There is a] lack of any obvious visible damage in the facade where the tail should have hit it; … I am not aware of the markings which J. Hoffman may have discovered … . The height of the damage to the facade of the building was much less than the height of the aircraft’s tail."

"You write, 'It is possible that the tail was blown off and fragmented, and did not reach the wall intact.' This type of explanation could be applied to the column [undamaged column 18] as well. I have two problems with it. First, in practical terms, an explosion would not change the fact that there were tons of matter on the move. An explosion would divert matter in all directions, but it would also accelerate part of the debris to an even greater velocity (and momentum) to the direction of the facade. That explosions would create areas devoid of visible damage in the relatively soft limestone wall -- do you find this credible?"

"Second, from the scientific viewpoint the statement quoted is extremely problematic, because it is, in practice, not falsifiable. (We cannot get anyone flying B-757s into limestone facades.)"

"As I see it, there is no explanation to the lack of damage …. In my view, then, the crash of a B-757 is a theory that contradicts our observations."

Comment 4: - By: John D. Wyndham - Posted: 05/16/17

Response from Scientific Method 9/11 to Sami Yli-Karjanmaa's comment of 05/16/17

Thank you for your comment.

With regard to the scientific method, it is important to note that this method considers all observations before accepting or rejecting an hypothesis and formulating a theory.

While Pentagon researchers have noted the absence of a clear gash in the Pentagon façade corresponding to the vertical tail fin of a Boeing 757, there was indeed façade damage up to the height of such a tail of approximately 45 feet, as shown by Jim Hoffman [1]. This damage extended almost to the top of the fourth floor, or a height of almost 50 feet. The Pentagon Building and Performance Report recorded significant damage up to the third floor slab, and minor damage up to the fourth floor [2]. In contrast, there was a clear gash in the façade caused by the plane’s right wing which impacted the wall intact [3]. From these two different observations, one can conclude that the vertical tail fin did not reach the wall intact. Can we explain why only fragments of the vertical tail fin reached the wall? The answer is ‘Yes.”

The” tons of matter on the move” were mainly the plane fuselage, wings and engines. The plane’s fuel was in wing tanks and in the center tank in the fuselage between the wings. The massive fuel explosion occurred when these tanks impacted the wall. At the time of the fuel explosion, the tail had not reached the wall, and there are witnesses who could still see the tail when the explosion occurred. Plane tails are relatively light and have been blown off (detached from the plane) by turbulence (see the example reported by Jim Hoffman) [4]. As for the statement that the fuel explosion would accelerate debris, including tail debris, “to the direction of the façade,” the opposite appears to be true

Plane parts, including large pieces, were blown back away from the wall and landed all over the lawn and the roadway, damaging cars. Plane pieces were picked up by motorists. According to eyewitnesses Penny Elgas, Terry Morin, and Steve Storti, the plane tail was still visible when the explosion occurred [5]. Because of the 52 degree angle of attack between the plane path and the wall, the plane tail presented a significant surface to the force of the explosion. It is highly credible that the tail was blown to bits and the bits mostly traveled away from the façade. Only some of the tail pieces reached the façade to cause the observed damage.

Scores of eyewitnesses observed the plane as it traveled toward the Pentagon. Of these, 62 or more eyewitnesses saw the plane hit the wall. In addition there is much physical evidence of large plane approach and impact including the clipped tree, downed light poles, and damage from engines to the low concrete wall and generator-trailer [6]. Eyewitnesses Steve Riskus, Ryan James, and Mike Walter described the tail and its markings, specifically the large double AAs logo [7]. Here is one testimony of an eyewitness to the aftermath [8]:

Blast expert Allyn E. Kilsheimer was the first structural engineer to arrive at the Pentagon after the crash and helped coordinate the emergency response. "It was absolutely a plane, and I'll tell you why," says Kilsheimer, CEO of KCE Structural Engineers PC, Washington, D.C. "I saw the marks of the plane wing on the face of the building. 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." Kilsheimer's eyewitness account is backed up by photos of plane wreckage inside and outside the building. Kilsheimer adds: "I held parts of uniforms from crew members in my hands, including body parts. Okay?"

There is an explanation for the relative lack of damage from the impact of a vertical tail fin. Taking all the evidence into consideration, we can conclude that a large plane impacted the Pentagon on 9/11. The resulting fuel explosion fragmented the plane tail so that only fragments reached the Pentagon wall.


[1] Jim Hoffman, Pentagon - Exterior Impact Damage.
See also John D. Wyndham, Is There No Visible Damage to the Façade from the Tail?, page 18.

[2] Pentagon Building and Performance Report, page 20.

[3] Pentagon Building and Performance Report, figure 5.12, page 29.

[4] Jim Hoffman, Lateral Displacement of Tail Damage Suggests Explosion

[5] What really Happened, 9/11 Pentagon Eyewitness Accounts

[6] Ashley et al., The Pentagon Event: The Honegger Hypothesis Refuted

[7] Arabesque, “Witnesses observed the tail of the plane” and “Plane Debris”.

[8] Testimony of Allyn E. Kilsheimer quoted by Salem News