Section 3: Breakaway Light Poles
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Frangibility Requirement
The FHWA adopted Section 7 of the 1985 AASHTO publication entitled ôStandard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signalsö for implementation beginning in July 1990. This section requires more stringent breakaway characteristics. TxDOTÆs previous design of roadway illumination assemblies (based on a 1975 AASHTO specification) does not meet these requirements.

Breakaway light poles rely on frangible transformer bases to provide the breakaway feature. The 1985 AASHTO specification provides for a maximum change in momentum of a 1800 pound car to break the pole away. The 1975 AASHTO specification provided for a similar change in momentum except that the test vehicle weighed 2,250 pounds.

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Structural Requirement
While providing the necessary frangibility, the base must also be structurally adequate to support the illumination pole for design wind speeds. Transformer bases meeting the Æ85 AASHTO specification may not adequately support some 50 foot steel poles, notably those designed to meet the Æ75 AASHTO specification.

PENTAGON RESEARCH


LAMP POLES


5 aluminum lamp poles were knocked down preceding the Pentagon wall. Through contact with the VDOT, the distributors and manufacturers of the poles used in the area I have been able to determine the following basic information.*

1) The poles were breakaway style on a 18 inch transformer style base. This means that at 23 inches off the ground the pole would be broken by a Volkswagen Rabbit traveling 20 mph.
2) The poles themselves were 27.66 feet high with a weight of approximately 175 pounds.
3) The truss style mast arms were 8 foot long with a rise that brought the pole height up to 30 feet. The mast arm weighs between 15-20 pounds.
4) The lamp head weighs approximately 70 pounds.
5) The aluminum on the poles was .188 of an inch thick. The pole was 8 inches in diameter at the base and 4.5 inches in diameter at the top.

Since the light poles are the first physical damage we encounter at the Pentagon I will break the rest of this page into a consideration of them in light of a plane and a no-plane point-of-view. This is very important in order to continue on into the rest of our investigation. The damage preceding the Pentagon wall has to be logically accounted for in either scenario.

PLANE

At the speed of 345 mph which was recorded by the recovered AA77 flight data recorder, the leading edge of the wing could slice through the approximately 5 inch diameter pole (at that height) with .188 of an inch thick aluminum walls like butter. This would cause the top half of the pole to pop up over the wing and essentially fall straight back down, which is effectively what we see with all the poles in the photos. The bottom half of the pole would have been driven forward with little resistance. If a VW Rabbit can break one at 20 mph 23 inches off the ground then it takes significantly less force with the leverage effect of being hit higher up. This may be why we have minimal wing debris on the ground.

This limited damage factor is why the FAA requires these type of poles in the "safety zones" around airports and helipads. They recognize that this type of pole minimizes damage to aircraft, "FAA regulation requires any structure located within 250 feet of runway centerline has to be frangible, which means the structure needs to break away when hit by an aircraft to minimize damages to the aircraft and its pilot." (Source)

One of the most commonly reported features in the eyewitness reports was the aircraft impacting light poles. In conjunction with the reported striking of the poles many eyewitnesses mentioned a change in the sound of the engines. Some described it as the engines being "revved up" or the aircraft going to "full-throttle".

The minimum wingspan required to create the pole damage was approximately 100 feet. The maximum wingspan before you would have had additional poles impacted is approximately 140 feet. The wingspan of a 757-200 is 124 feet 10 inches. This accounts for the minimum of 100 feet and allows for a 16 foot tolerance which is exactly what we see in the diagrams.

The first pole impact occurred at approximately 1000 feet prior to the Pentagon wall. 345 mph is 506 per second. That means it would have been roughly 2 seconds with the aircraft being driven by momentum between the first pole and the wall. There would not have been the force or the time for the pole damage to cause a deviation in the flight-path.

The following video exemplifies evidence for an aircraft hitting the Pentagon including the poles. I spoke with the creator of this and clarified that they built their model and let what happened happen. The right engine ingesting the lamp head on pole number 3 was not programmed into their scenario, it was predicted by the model. This would explain the change in the engine sound reported by witnesses and the anomalous vapor trail at ground level seen in the DoD videos.


NO PLANE

If there was no plane or an aircraft with a wingspan of less than 100 feet then the light pole damage would still have to be accounted for. The no plane proponents suggest a faking of this damage. I will just list the implications of this scenario since I have not come across a realistic explanation for how this could have been done.

1) The perpetrators would have to have decided on what type of aircraft and what the wingspan of the "imaginary" plane would be in advance.
2) They would have to have agreed on a flight-path and predetermined the poles to be "damaged".
3) They would have to have had caused the poles to break up high and at the base assuming an imaginary altitude for the aircraft.
4) They would have to have had total control of all witnesses in the area including suppressing the witnesses who noticed the poles falling for no reason.
5) They would have to have had briefed the controlled witnesses on the type of plane, the flight-path, the poles being hit and the change to the engine sound.
6) They would have to have synchronized the falling of the poles with the explosion at the wall.

That gives just some idea of what you are up against in a no plane scenario. Keep in mind when you look at the photos in the sidebars there is no evidence of explosives at the upper break or the base of the poles. Also, remember they would have gone to all of this trouble to account for about 12 feet of altitude. Why not just say the plane came in at a slightly steeper angle?

* The information on the poles is representative of the poles in the area. They had different manufacturers and distributors over the years. I could not acquire information specific to the exact poles impacted. One of the main manufacturers is Union Metal.