RADAR (ICAO) - A radio detection device which provides information on range, azimuth and/or elevation of objects.

(1)
PRIMARY RADAR - A radar system which uses reflected radio signals.

(2)
SECONDARY RADAR - A radar system wherein a radio signal transmitted from a radar station initiates the transmission of a radio signal from another station.

RADAR (JCS) - A radio detection device which provides information on range, azimuth and/or elevation of objects.
RADAR ADVISORY (P/CG, JCS) - The provision of advice and information based on radar observations. (See Advisory Service)
RADAR APPROACH (P/CG) - An instrument approach procedure which utilizes Precision Approach Radar (PAR) or Airport Surveillance Radar (ASR). (See PAR Approach, Surveillance Approach, Airport Surveillance Radar, Precision Approach Radar, Instrument Approach Procedure)
RADAR APPROACH (ICAO) - An approach, executed by an aircraft, under the direction of a radar controller.
RADAR APPROACH CONTROL FACILITY - A terminal Air Traffic Control facility that uses radar and non-radar capabilities to provide Approach Control service to aircraft arriving, departing, or transiting airspace controlled by the facility (see Approach Control Service). Provides radar Air Traffic Control service to aircraft operating in the vicinity of one or more civil and/or military airports in a terminal area. The facility may provide services of a Ground Control Approach (GCA); i.e., Airport Surveillance Radar and Precision Approach Radar approaches. A radar Approach Control facility may be operated by Federal Aviation Administration, US Air Force, US Army, US Navy, US Marine Corps, or jointly by Federal Aviation Administration and a military service. Specific facility nomenclatures are used for administrative purposes only and are related to the physical location of the facility and the operating service generally as follows:
Army Radar Approach Control/ARAC (Army)
Radar ATC
Facility/RATCF (Navy/Federal Aviation Administration)
Radar Approach Control/RAPCON (Air Force/Federal
Aviation Administration)
Terminal Radar Approach Control/TRACON
(Federal Aviation Administration)
Tower/Airport Traffic Control Tower/ATCT (Federal Aviation
Administration)
(Only those towers delegated approach control authority).

RADAR ARRIVAL - An aircraft arriving at an airport served by a radar facility and in radar contact with the facility. (See Non-radar Arrival)
RADAR BEACON - (See Radar)
RADAR BEACON (JCS) - A receiver/transmitter combination which sends out a coded signal when triggered by the proper type of pulse, enabling determination of range and bearing information by the interrogating station or aircraft.
RADAR CLUTTER (ICAO) - (See Clutter)
RADAR CONTACT (P/CG) -
(1)
Used by Air Traffic Control to inform an aircraft that it is identified on the radar display and radar flight following will be provided until radar identification is terminated. Radar service may also be provided within the limits of necessity and capability. When a pilot is informed of “radar contact” he automatically discontinues reporting over Compulsory Reporting Points. (See Radar Flight Following Radar Contact Lost, Radar Service, Radar Service Terminated).