FAA ARSR-4 Radar

The Air Route Surveillance Radar (ARSR-4) is used by Homeland defense and the Federal Aviation Administration to control airspace within and around the borders of the United States.

The ARSR-4 is the FAA's newest (late 80s, early 90s) addition to the "Long Range" series of radars, search radars with a range of at least 200 nautical miles (370 km). The Westinghouse system is solid state and has a 250-nautical-mile (460 km) range. A Beacon system, typically an ATCBI-5, but increasingly ATCBI-6M, will be installed along with an ARSR-4. However, the ARSR-4 is capable of determining aircraft altitude independently of its associated Beacon (albeit less accurately).

ARSR-4 systems are installed along the borders and coastal areas of the CONUS.