Definition
An older generation of Airport Surveillance Radar used by Terminal Radar Approach Control (TRACON) facilities to detect and display the position of aircraft within roughly 60 nautical miles of an airport. ASR-3 is a short-range primary radar system that provides controllers with bearing and distance information for sequencing and separating aircraft in the terminal area.
Plain English
A specific model of the radar system that controllers near an airport use to see where aircraft are. It shows the controller a picture of the planes within about 60 miles of the field so they can keep them apart and line them up for approach.
Context Anchor
Seen in discussions of TRACON radar equipment and the radar information available to controllers during instrument operations near busy airports.
Derivation
ASR stands for Airport Surveillance Radar. 'Surveillance' comes from the French surveiller, meaning 'to watch over.' The '-3' simply indicates it is the third generation of this radar series. So the name literally means 'the third version of the radar that watches over the airport area.'
Why Pilots Care
When a controller says they have you on radar in the terminal area, this is the kind of equipment painting your aircraft on their scope. Knowing the rough range (about 60 NM) helps you understand when terminal radar services begin and end during your approach or departure.
Grounding Statement
ASR-3 equipment is part of the controller’s view of traffic near the airport.
Intuition Check
ASR-3 equipment is not a procedure, clearance, or approach by itself. It is the radar hardware used by controllers to see aircraft positions.
Example Sentence 1
The TRACON's ASR-3 equipment provided controllers with the position of arriving traffic within 60 miles of the airport.
Example Sentence 2
Even without a working transponder, the pilot's aircraft remained visible to the tower on ASR-3 equipment.