810th AC&W Squadron

Dedicated to the 810th Radar Squadron and all the US Air Force Radar Sites of the Past

810th History and Hardware

810th History

M-130/Z-130 - Winston-Salem (A-6, A-S/GCI)

Funding shortfalls in FY 1957 forced the Air Defense Command to hold up construction at this site. However, the 810th AC&W Squadron finally began operating ANLMPS-11 and AN/FPS-GA radars in late 1957. The ANLMPS-11 set was replaced by an AN/FPS-8 set that saw service between 1960 and 1962.

In 1962 the 810th began operating AN/FPS-24 search and AN/FPS-26 height-finder radars along with the previously installed AN/FPS-6 set. In 1963 Winston-Salem began providing data for the SAGE system.

The Air Force deactivated the 810th in July 1970.

Hardware - 1966 to 1969

AN/FPS-24 Search Radar

The AN/FPS-24, such as the unit at Winston Salem was developed as part of the Frequency Diversity Radar program, a major radar developmental project undertaken at RADC (Rome Air Development Center, Griffiss Air Force Base, Rome, NY). In addition to the AN/FPS-24 this program was also responsible for the AN/FPS-26, AN/FPS-27, AN/FPS-28, and the AN/FPS-35, frequency diversity radars.

This equipment was designed to succeed existing Semi-Automatic Ground Environment (SAGE) radar systems, which had served as the backbone of air defense of the CONUS, in order to provide enhanced electronic counter countermeasures (ECCM) capability.

The AN/FPS-24 at Winston Salem was built by General Electric, and the system was manned by a handful of GE civilian contractors along with an Air Force crew. This radar was designed to operate in the Very High Frequency (VHF) range between 214 and 236 MHz.

A number of problems were encountered with this radar when it underwent initial testing at the test site at Eufaula, Alabama, in 1960. As a result the system underwent many modifications before it was finally deployed.

A total of twelve AN/FPS-24 systems were built between 1958 and 1962. The AN/FPS-24 radar, became operational within the SAGE system on 30 June 1968.

When the radar was initially deployed in 1961, bearing problems often occurred due to the eighty-five ton weight of the antenna. The use of a hydrostatic bearing solved this problem. The development of this bearing was the work of Goodyear Aerospace, under contract with RADC.

The bearing in the AN/FPS-24 at the 810th was not replaced in the 3 plus years I was there. I recall there was a weekly shutdown of the system for preventative maintenance, and one of the tasks performed during these periods was an inspection of the bearing. I was not involved in this, but I was told that some number of rollers were inspected each week, so over some period of time all the rollers would be looked at. I believe this involved jacking up the sail and physically removing the rollers. Individual rollers could be replaced as needed.

A few months before I left a large flatbed tractor trailer truck pulled in delivering a replacement bearing. The single roller bearing arrived in a large wooden crate that extended over the sides of the flatbed! I believe the site was closed before that new bearing was ever installed. I'll bet that part cost the taxpayers a tidy sum and I doubt it had many other applications!

I also recall the 24 being shut down for several months while a major retrofit was performed. This would have probably been in 1968. A group of contractors from GE did most of the work. They chopped out a bunch of hardware and piles of cables and added some newer gear. Being a bit of a pack rat I grabbed some of the old parts out of the trash and may still have a few of them in my basement.

Among the electronic components I recall seeing at this time was some capacitors rated in farads. Each of these were about the size of a bathtub! Today you can find caps of similar value on the motherboard of your PC.

AN/FPS-26 Height Finder Radar

Another product of the Air Force Rome Air Development Center [RADC] Frequency Diversity Radar program was the AN/FPS-26. This system was designed to succeed existing Semi-Automatic Ground Environment (SAGE) radar systems, which had served as the backbone of air defense of the CONUS, in order to provide enhanced electronic counter countermeasures (ECCM) capability.

Avco Corporation built this height-finder radar and it entered service on 20 January 1960.  RADC accepted the AN/FPS-26 air defense radar from AVCO after stipulating that the contractor must correct certain component deficiencies that were encountered during testing. This radar operated at a frequency of 5400 to 5900 MHz.

Although I did not work directly on this system, a friend who did invited me inside the inflated radome during an extended maintenance shutdown. I recall the scene of the sparkling gray height finder dish under the bright lights under the dome looked like something from a science fiction movie. Unfortunately I didn't bring my Polaroid camera through the air lock. Unlike the electric motor driven AN/FPS-6, the AN/FPS-26 was all hydraulically driven.

AN/FPS-6 Long-Range Height Finder Radar

The AN/FPS-6 radar, developed at RADC, was the first long-range height finder radar employed at all Semi-Automatic Ground Environment (SAGE) locations. This system had a maximum range of 200 nautical miles and a height-finding capacity of 75,000 feet within an angle limit of minus 2 to plus 32 degrees.


The AN/FPS-8 was gone when I arrived, but the round metal building that housed it was still present. We used it as a storage shed for maintenance equipment and supplies along with old out of service parts for the Radar gear.

Among the items kept in there were drums of dry powered chlorine for treating the water in the AC cooling towers. A couple of times a week we would grab a bucket of the stuff and dump some in each cooling tower. One of the HVAC techs, a guy named "Shorty Krosp" as I recall, claimed he could cure a cold by sticking his head in the chlorine drum and taking a deep breath. I tried it once. It didn't work and I thought I was gonna die!

John Kessler (copyright, Nineveh Junction Digital, john@nineveh-junction.com) - Updated 3 Nov, 2006