Radar is an electronic system which measures the range and bearing of objects by transmitting an electromagnetic pulse at the object and listening for the echo.
Many types of radar are in use in aviation.
- Area Radars, Surveillance Radars, and Approach Radars allow controllers to track aircraft within their area of responsibility;
- Precision Approach Radars (PAR) enable controllers to provide precision approach guidance to aircraft landing in instrument conditions;
- Surface Movement Radar enables controllers to track the movement of aircraft and vehicles on an aerodrome surface;
- Weather Radar gives pilots situational awareness of hazardous weather, especially Thunderstorms;
- Radio Altimeters accurately measure the height of an aircraft above the surface;
- Secondary Surveillance Radar enables aircraft to pass additional information, such as identification and flight level, back to the interrogating radar.
Primary Surveillance Radar
Secondary Surveillance Radar
Radar service may be used for the identification, traffic co-ordination and separation.
Types of Air Traffic Radar Service
Three types of air traffic radar service may be available within the coverage of air traffic radar systems:
- Radar Control Service, provided to aircraft operating in controlled airspace;
- Radar Advisory Service, provided to aircraft operating in advisory airspace; and,
- Radar Information Service, provided to aircraft operating outside controlled and advisory airspace.