The Avco AN/FPS-26 Radar was an Air Defense Commandheight finderradar developed in the Frequency Diversity Program with a tunable 3-cavity power klystron for electronic counter-countermeasures (e.g. to counter jamming). Accepted by the Rome Air Development Center on 20 January 1960[3] for use at SAGE radar stations, the AN/FPS-26 processed height-finder requests (e.g., from Air Defense Direction Centers) by positioning to the azimuth of a target aircraft using a high-pressure hydraulic drive, then "nodding" in either a default automatic mode or by operator command. The inflatable radome required a minimum pressure to prevent contact with the antenna which would result in damage to both (technicians accessed the antenna deck via an air lock.) To maintain high dielectric strength, the waveguide was pressurized with sulfur hexafluoride (SF6), which technicians were warned would produce deadly fluorine if waveguide arcing occurred.[4]
Under the Joint Electronics Type Designation System (JETDS), all U.S. military radar and tracking systems are assigned a unique identifying alphanumeric designation. The letters “AN” (for Army-Navy) are placed ahead of a three-letter code.[6]
The first letter of the three-letter code denotes the type of platform hosting the electronic device, where A=Aircraft, F=Fixed (land-based), S=Ship-mounted, and T=Ground transportable.
The second letter indicates the type of equipment, where P=Radar (pulsed), Q=Sonar, and R=Radio.
The third letter indicates the function or purpose of the device, where G=Fire control, R=Receiving, S=Search, and T=Transmitting.
Thus, the AN/FPS-26 represents the 26th design of an Army-Navy “Fixed, Radar, Search” electronic device.[6][1]
The foreground radome with dark-clad support structure houses a USAF AN/FPS-26A just completing construction c. late 1962 at the Missile Master military installation at Fort Lawton Air Force Station, which had a Direction Center in the nuclear bunker. The two radars without radomes are US Army AN/FPS-6 heightfinders; the radome with an open steel grid support structure is an FAA search radar; and the two radars with radomes and white clad support structures are USAF AN/FPS-6A heightfinders.
This article incorporates public domain material from the Air Force Historical Research Agency
