Space Fence - Hazardous? Restricted?

CT4ME

CT4ME

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I was watching a show on the Discovery channel about secret US government facilities... the Space Fence was mentioned. It's official name is "Air Force Space Surveillance System". The system tracks, with precision, all orbiting satellites and space junk. There are 9 facilities across the US, on the 33rd Parallel. 3 facilities transmit an intense, narrow, radar beam into space, and the other 6 units receive the reflections. The transmitting towers are in Lake Kickapoo, Tx, Gila River, AZ, and Jordan Lake, Alabama.
So, I was wondering about seeing the facilities from the air, since they are a huge, flat, antenna as much as a mile long. Since one is very close to phoenix, I thought I'd find out where it was.
In researching the facility I have two questions: Are the facilities Hazardous to airplanes?:confused: and Is the facility "restricted" to overflight?:confused:
I ask because, in a recent article about the facility, the operators said that they track and report tail numbers of aircraft doing fly-overs, as it was "restricted"... and, in big letters at the end of the facility are the huge letters "HAZ", obviously meant for pilots, and presumably meaning "Hazardous".
I don't see the spot listed as restricted on charts.
Anybody know anything about these facilities, as they relate to flying?
http://www.inmaricopa.com/Article/2012/03/10/air-force-space-command-defense-surveillance
ps. The Gila River facility is very close to, if not exactly, where the recent mid-air with no injuries happened. I only mention this as a reference to location, with no insinuations concerning cause.
 
You can see it on Google about 2 miles north of Maracopa City. Rt 347 to a left with a right dogleg right after the guard building. It appears the "radar" is a 1/4 strip to the left side of the main building.
Google street view doesn't focus on the facility's sign.
 
There is a listening station in southern AR for the Space Fence. I have flown over it several times. Its kinda neat to look at from the air.

The only danger I can think of is radiation burns and RF over exposure. However that would be only located at and a few feet around the transmitters. That is why of course the area is fenced off with razor wire. People think its some type of government cover up. Nope its mainly to keep idiots and wildlife from hurting themselves or the station.

Denver: How much power do you think the transmitters need to be harmful to aircraft? I think it has to be somewhere north of 50,000 WATTS
 
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ARFlyer said:
Denver: How much power do you think the transmitters need to be harmful to aircraft? I think it has to be somewhere north of 50,000 WATTS
Click to expand...

We talking transmitter power or ERP? I have no idea how focused that energy is above those, but my one look at the tech long ago seemed to indicate the power levels were pretty low (relatively) and the system worked on detecting the Doppler shift of the echoes at... I think it was UHF?... Of anything crossing the "fence".

There was a request long ago to see if Amateurs could hear an object that was passing through the fence, ARRL was the communications outlet for that request.

The big power stuff is PAVE PAWS with their monster arrays focusing a buttload of RF. I don't think I'd want to fly through that on purpose. Love the look of the antenna sites though. 105' high building just to hold a UHF antenna. :)

http://en.m.wikipedia.org/wiki/PAVE_PAWS

Do you remember the big deal it was when USAF exercised their Primary spectrum allocation rights for the "Amateur" UHF spectrum and forced repeaters within a particular distance of PAVE PAWS facilities to reduce power to relatively tiny levels? With no adjacent frequency interference, those beasts can "see" objects a ridiculous distance away. That was going on back in 2007 or so.

I suspect that the fences are WAY below the energy levels of PP, and much less concentrated.
 
ARFlyer said:
Denver: How much power do you think the transmitters need to be harmful to aircraft? I think it has to be somewhere north of 50,000 WATTS
Click to expand...
Depends on the wavelength, distance from the antenna, and field density (focus) of the antenna pattern. Also the issue is generally a function of average power, not pulse peak power which could be thousands of times higher than average power.

In any case, I believe it would take a lot less than 50KW average ERP in the millimeter wavelength bands to be hazardous if focused to diffraction limits at flyable altitudes.
 
kkoran said:
Restricted: No. If it were, it would be on the charts.

Hazardous: Doubt it. If it were, I assume there would be a warning note on the Sectional Chart similar to the one on the Honolulu Sectional.
Click to expand...

Yes. You want to avoid that radiation area. And you want to avoid the entire restricted airspace along the Waianae range unless you want to practice your intercept procedures with aircraft carrying live war loads. :eek:
 
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