Restricted Areas

8. JSS Ajo & Joint Surveillance Sys in a nutshell

Last modified: 13 Jun 2022

Country: United States    Region: Arizona

Latitude: 32° 25' 50" N     Longitude: -113° 3' 18" E

Area use / Military Branches: Active


Grid 3225'50.11"N 11256'41.20"W Joint Surveillance System radar
Q. What is Joint Surveillance System:(JSS)?
A. The current joint USAF and Federal Aviation Administration radar system for North America. It replaced the former Semi Automatic Ground Environment (SAGE) system in 1983.

Q How is it working?
A. JSS consists of long range surveillance radars, operated and maintained by the Federal Aviation Administration (FAA) and providing communication and radar data to both FAA and United States Air Force control centers. The equipment is a mix of Long Range Air Route Surveillance Radars (ARSR) of various types and military AN/FPS type radars. They are co-located with UHF ground-air-ground (GAG) or ground-air-transmitter/receiver (GATR) facilities at many locations and many sites have VHF radios as well. GATR facilities provide radio access to fighters and Airborne Early Warning & Control (AEW&C) aircraft from the Sector Operations Control Centers.

JSS has been enhanced under the Combined Radar Replacement Program with 44 ARSR-4 / FPS-130 radars to replace some of the many previous long-range radars. This provides common, high-performance, unattended radars as these are unattended except for periodic FAA maintenance crews visiting the sites. ARSR-4/FPS-130 is a 3-D long range radar with an effective detection range of some 250 miles and has been fully integrated with JSS at all joint use sites.

Q. What is a Sector Operations Control Center (SOCC) ?
A. A SOCC is responsible for collecting and analyzing all radar data in its sector. Based on that it commands and controls the airdefence assets in its sector which may be deployed to counter threats.

JSS radars transmit data to the SOCCs who then forward tracks of interest to the CONUS ROCC and NORAD. Radar and track data are sent through landlines as TADIL-B data and through HF links as TADIL-A data. Both links are provided by the Radar Data Information Link (RADIL). CONUS SOCCs communicate with the CONUS ROCC and NORAD by voice and data landline circuits.

This location is former AFS Ajo (1953-1970). Activated 1958 with 612th Aircraft Control & Warning Sqn being assigned to the new station by the 34th Air Division. Initially, 612th AC&W Sqn operated AN/FPS-20A and AN/FPS-6 radars and functioned as a Ground-Control Intercept (GCI) and warning station. As a GCI station, the squadron's role was to guide interceptor aircraft toward unidentified intruders.
1961 Ajo AFS joined the Semi Automatic Ground Environment (SAGE) system, feeding data to DC-21 at Luke AFB, Arizona. After joining, the squadron was redesignated 612th Radar Squadron (SAGE) and 1963 the site was redesignated NORAD ID Z-181.
612th Radar Squadron deactivated 1970.
Site reactivated as a JSS facility operating as an ARSR-4 radar and a communications site for the Barry M. Goldwater USAF Range. The former USAF site also hosts an Air Combat Maneuvering Instrumentation (ACMI) antenna on top the old AN/FPS-26 radar tower.

The other JSS radars in the state of Arizona are Humboldt Mtn (closed 2000) at grid 3358′53″N 11147′53″W and Seligman at 3521′10″N 11256′59″W (ARSR-4 radar)

Search for 8. JSS Ajo & Joint Surveillance Sys in a nutshell

Your Message

Name *
(Plain Text Only)

Security Code*

Please insert the security code.

* Required Fields

Top         Home