Physical and mathematical analysis of Pentagon incident.     by Gerard Holmgren

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It is not in dispute that something hit the Pentagon wall and damaged it. Neither is it in dispute that AA 77 is missing. But was AA 77 involved in the Pentagon incident? This article presents an analysis of the physical aspects of the incident, and concludes with a brief examination of the issue of eyewitnesses

 

WHERE IS THE WRECKAGE OF AA 77?
INSIDE THE BUILDING?
OUTSIDE THE BUILDING?
CREMATED?
OR NEVER THERE?

INTRODUCTION

It is alleged that on Sept 11, 2001 a hijacked Boeing 757, American Airlines Flight 77, hit the Pentagon. It is not in dispute that something hit the Pentagon wall and damaged it. Neither is it in dispute that AA 77 is missing. But was AA 77 involved in the Pentagon incident? This article presents an analysis of the physical aspects of the incident, and concludes with a brief examination of the issue of eyewitnesses.

The Sept 11 crashes are unique and unprecedented events in the history of both the press and aviation. In many cases, light plane crashes involving 2 to 3 people have triggered investigations which continued for years. Considering that the explosion and cremation of planes had never before happened, the lack of reporting and/or official investigation is doubly puzzling. The issue of whether a crash results from sabotage or accident should be irrelevant to the alarming question of why four planes allegedly cremated themselves as a result of low to medium impact crashes.

One of the purposes of accident reconstruction in plane crashes is to determine what failed and therefore what is subject to improvement. Normally, the press releases the findings as news in the public interest. Professional analytical information has not been released on the September 11 crashes. If it exists (for insurance purposes, for instance), it has not been released. Why have authorities and the press treated the Sept 11 crashes differently? Who is doing the professional analysis and why does the public not have access to it?

 

PART 1. PLANE SPECIFICATIONS

Sourced from http://a188.g.akamaitech.net/f/188/920/15m/http:/www.washingtonpost.com/wp-srv/nation/graphics/attack_757200.htm

and http://www.boeing.com/commercial/757family/pf/pf_200tech.html

Wingspan 124 ft 10 in (hereafter rounded to 125 ft) Length 155 ft 3 in (rounded to 155 ft) Tail height (with landing gear extended ) 44 ft 6 in Fuselage Width 12 ft 4 in (rounded to 12 ft ) Max fuel capacity 11,489 gallons Max range 4449 miles Max take off weight 255,000 lb.

The following specifications were not directly available from any source I could find, but I calculated them based on the above figures, after measuring diagrams and photos. Exact accuracy cannot be guaranteed, but they are close and are sufficient for this analysis.

Tail height (without landing gear extended) 35 ft Fuselage height (without landing gear extended) 14 ft 6 in (7 ft 3 in above wings, 7 ft 3 in below wings)) Length of each wing 56 ft 3 in Engine diameter. 9 ft. 6 in Engine length 11 ft 6 in Position of engine mounting on wing. Outer edge of engine 25 ft from where wing joins fuselage. Width of each tail fin 15 ft 6 in Total tail fin span 39 ft (fuselage is narrower at this point) An estimated 5 ft of engine is below fuselage level, making the total height of the aircraft without landing gear extended, 40 ft.

You’ll find the calculations throughout this article easier to critically analyse, if you write down the above figures before continuing.

 

PART 2. ESTIMATIONS OF HOLE DIMENSIONS

Based on this and other similar photos,
http://www.pbase.com/image/536173

I have estimated the hole in the Pentagon wall to be about 65 ft wide, by comparing it with the height of the building which is 77 ft.

http://www.defenselink.mil/pubs/pentagon/facts.html

Depth of damage. This is more complex. The Pentagon consists of 5 rings of building, each separated by a space between. I couldn’t find any source which directly stated figures for the depth of the rings and the spaces, and the perspective problems of photos make it more difficult to estimate than the width. On the basis of aerial photos, ( see the links below ) I have estimated the depth of the ring itself to be about 32 ft, and the open space behind it, about the same. The outer ring collapsed , leaving a total depth of about 65 ft that the plane could potentially have fitted into, considering that the second ring of the building was intact.

http://www.defenselink.mil/photos/Sep2001/010914-F-8006R-002.jpg
http://www.asile.org/citoyens/numero13/pentagone/erreurs_en.htm

It should be noted that the original hole was much smaller. The 65 ft wide hole developed when a section of the wall collapsed later.
Look at the following photos, taken soon after the crash, before that section of wall collapsed. The thick smoke and the water jets from the fire fighters make it difficult to get a clear view, but we can determine that the hole wasn’t anywhere near even 40 ft wide. Probably less than 20. In most of the photos, it’s difficult to find any hole at all.

http://66.129.143.7/june2aa.htm
http://www.asile.org/citoyens/numero13/pentagone/erreurs_en.htm
(see the two photos in question 7 )
http://www.ifrance.fr/silentbutdeadly/
(click on the trajectory section and scroll to the photo with the caption “Hole center” and the subsequent photos)

Calculations based on the 65 ft wide and deep (including open space between the rings) hole which developed later, are unreasonably generous to the 757 argument. Nevertheless, I will continue to conduct the analysis on that basis. I am going to attempt to prove that it was physically possible for a Boeing 757 to crash into that section of wall, in a manner consistent with the photographic evidence. If I manage to prove that it was physically possible, that doesn’t prove that it happened - it simply keeps the argument alive. If it proves to be impossible, even by expanding the assumed hole to orders of magnitude greater than what it really was, then it didn’t happen and the argument is concluded.

 

PART 3. ENTRY IMPACT CALCULATIONS AT 90 DEGREE FUSELAGE ANGLE

By what means could a plane with a wingspan of 125 ft and a length of 155 ft fly into a building, leaving a hole 65 ft by 65 ft, leaving no significant wreckage outside? Is it possible to calculate a wing angle at which the plane might have fitted through? If not, where is the wreckage that did not enter the building?

The plane cannot have impacted with the wings in a near parallel to the ground position and have had the wings enter the building. If it impacted in this manner, the wings must have broken off before they had a chance to hit the building. 125 ft of wing cannot pass through a wall without leaving a 125 ft hole. In order to suggest that the entire plane passed through the 65 ft hole, we must calculate the angle at which the wings would have to have been tilted.

This can be easily done with some graph paper.
Draw a baseline, representing 65 ft - the width of the hole. Draw vertical lines at each end, representing 77 ft - the height of the building. Draw a line representing 125 ft - the wingspan, starting it from the bottom left corner, towards the top right corner, at the angle necessary for the wingspan line not to intersect the right hand vertical line. You’ll see that it is possible for the plane to pass through the 65 ft wide hole, but not for all of the wingspan to pass within the impact area. A significant portion of one wing has passed above the building, avoiding any impact. This section of wing measures about 25 ft - almost 1/2 a wing.

The minimum possible amount of the plane which can have avoided the impact area is a figure something greater than this because the analysis has been biased by a number of factors, beyond credibility in favour of fitting the plane through.


1) assuming the original impact area to be 65 ft wide, when we know that it was significantly smaller.


2) assuming the lower wing tip to be at ground level, which it may not have been.


3) assuming the angle of the fuselage to the wall to be 90 degrees, meaning that the plane travelled straight through, not widening the impact area beyond it’s own effective horizontal width. For example, if the fuselage struck at a 45 degree angle, with the same degree of wing tilt, it would create an impact hole 97.5 ft wide.You can plot this on graph paper too. If you draw two parallel lines straight up the page, crossing a line drawn horizontally, the width of line they pass across is equal to the distance between the parallel lines. If you draw the lines at a 45 degree angle to the horizontal line, they intersect with an area 1.5 times the distance between them. So as soon as any angle is postulated for the approach of the fuselage, then the wings need to be tilted harder in order to fit into the 65 ft hole, increasing the amount of wing that passed above the impact area. If we postulate the wings to be tilted at a ridiculous angle like 80 degrees, not only does this increase the area of wing that’s passed above the impact zone, but also causes the fuselage to be almost at the top of the building, meaning that one of the 15 ft tail fins, now pointing almost straight up, starts to protrude above the impact zone. It doesn’t matter how the angle of approach or wing tilt is juggled. It’s impossible to fit anything remotely approaching the entire plane into the impact zone.

Therefore, this substantial portion of the plane did not hit the building and cannot have been pulverized amid the rubble, and must be accounted for in some other way.

To give an idea of how much the unaccounted for section of wing increases if we lessen the degree of bias, here is a different set of assumptions.
Original width of hole 40 ft. Lower wing tip 10 ft above the ground.
The amount of the wing which would now pass above the impact point would be about 47 ft. And the entire upper tail fin would no longer fit in sideways, because the bottom of the heavily tilted fuselage would be hard up against the right edge of the hole.The wing angle could be tilted more heavily to fit in the tail fin, but this further increases the length of wing passing above the impact zone. This is still assuming a fuselage angle of 90 degrees, and a hole larger than what it really was. So we have to stretch the variables beyond credibility in favour of the 757 theory just to reduce the unaccounted for piece of wing to 25 ft.

Since this large portion of wing would not have had any serious impact upon it, there is no reason for it to have been pulverized into nothing, unless there was an explosion powerful enough to cremate the wings right to the extremities. If this did not occur, then this section of wing would have suffered no impact other than that of falling to the ground or on to a roof after it broke off. It’s conceivable that it could have broken up into a few smaller pieces, but not to have been pulverized beyond evidence of it ever existing. So there should be evidence of a large piece of wing, or several pieces, large enough to be clearly identifiable, outside the crash site, or possibly sitting on top of the rubble. Most likely, it (they) would have finished up somewhere inside the courtyard or on a roof. The chance of it finishing up on top of the rubble would be small, the chance of being buried under the rubble, negligible, and the chance of being under the rubble and smashed into pieces too small to identify, effectively zero.

No evidence exists of any such wreckage, and there is no reason why it should not have been found and presented if it existed. We must therefore conclude that if the 757 theory is to be kept alive, one has to postulate an explosion significant enough to cremate an entire length of wing beyond evidence that it ever existed. Because the only available energy source for such an explosion is the fuel, and an explosion must generate force equally in all directions, this forces us to the conclusion that most of the plane must have been similarly cremated by the explosion.There is also the problem of the tail. Being the last part of the plane to enter the building, the wall should already have been smashed down by the time it entered. So the tail should have suffered less impact than the forward part of the plane, increasing the likelihood of large identifiable pieces being found. That no evidence remains of it also forces us to postulate a massive explosion capable of cremating it.

Before examining this question further, I will now do the same style of analysis on the scenario of the plane hitting the wall with the wings approximately parallel to the ground.

If this happened, it is clear that the wings never contacted the wall. They certainly did not pass through. The hole is 60 ft too narrow, leaving 30 ft of each wing that cannot have passed through. And there is no evidence of any damage to the sides of the hole that would indicate contact of this type. If the wings did hit the wall, they can’t have simply bounced off, without leaving any damage to the wall, while simultaneously cremating themselves from the force of the impact. Especially if the fuselage was apparently able to plough significantly into the building, before being cremated. Not only is the fuselage penetration indicative of the test of strength between the wall and the plane, but the wall would have been weakened by being split open by the fuselage, making it easier for the wings and tail as they followed. So in the event of the wings being parallel, since no wreckage exists to support their existence, we must also postulate an explosion significant enough to cremate the wings to their extremities, in order to account for the two missing 30 ft sections.

Regardless of at what angle the wings may have been tilted, it is impossible for all of the wreckage to have been impacted, buried and crushed beyond identification within the rubble of the 65 ft by 65 ft area of wall damage. A significant section of at least one wing, something more than 25 ft long, never entered the impact zone, and cannot have been cremated by impact alone, and yet appears to have vanished. The lack of any other wreckage also indicates cremation. And since explosions generate force equally in all directions, one can’t postulate an explosion powerful enough to cremate the extremities of the plane - tail, nose and wing tips without postulating that the entire plane was cremated.

Therefore, it is either drop the 757 theory or postulate an explosion powerful enough to cremate the wreckage to the point that no evidence remains of it’s existence.

Before examining in detail the explosion question, lets look at the depth of the hole. 65 ft. The length of the alleged plane was 155 ft. Nothing identifiable remains of any part of the plane. If we were not to postulate an explosion we would have to suggest that the fuselage was compacted to 40% of it’s original length - at least, just to explain the lack of damage to the second ring. That’s assuming the entire depth of the first ring to have been burst through in the initial impact, and part of the compacted plane to have protruded out into the space between the two rings. But if such compacted wreckage came to rest there, it would be highly visible, and without a subsequent explosion, there is no way to explain where the compacted fuselage went. So the entire length of the plane needs to be compacted into the space of the first ring - about 30 ft - quite impossible. One would have to suggest that the fuselage compacted to about 20 % of it’s length against the unyielding wall, and then suddenly burst through, coming to rest inside as a 30 ft lump amongst the rubble. Or alternatively, that it was still being compacted even after it burst through, meaning that as the rear of the plane entered, the rubble and the compacted remains of the front of the plane, were still providing significant resistance, like a person trying to hold a door shut against a stronger opponent, and being gradually pushed back. This can’t happen. The wall either holds or it doesn’t. The plane either penetrates or compacts. It doesn’t do both simultaneously. It’s possible that there could have been a certain amount of compaction before penetration, but at some point the wall had to give way, and once it did, there would be no more compaction. If it’s going to give way, it will be early in the process. And yet, postulating a 50 % compaction of 90 % of the plane, before it suddenly burst through - which is quite impossible - would still leave a final fuselage length of 85 ft to be accounted for - also impossible. And this still leaves unsolved the problem of what happened to it afterwards.

There’s a severe problem not only with the width of the impact area, but also the depth. Neither the fuselage nor the wings can fit into the allotted space.

Postulating an angled entry slightly reduces the amount of compaction required, but not by the orders of magnitude necessary to fundamentally solve the problem. For example, if one was to redo the last calculation on the basis of a 45 degree entry, it would be reduced to a 42% compaction of 90 % of the plane before bursting through, leaving an 85 foot length of wreckage, which lying at a 45 degree angle, would leave about 37 ft of fuselage extending beyond the first ring, almost reaching the second. And there would now be either a wider entry hole, or a greater section of wing which missed the impact zone. .Although debris of some kind exists, there is nothing of enough substance to provide any evidence of what kind of plane it was, and the volume is insufficient to account for anything remotely approaching the dimensions under discussion. This is further proof that in order to keep the 757 theory alive, we must postulate an explosion which cremated the plane.

 

CONTINUE