Definition
An air traffic control service provided in a Terminal Radar Service Area (TRSA) to participating IFR and VFR aircraft, including sequencing of all aircraft to the primary airport and standard radar separation between IFR aircraft and between IFR and participating VFR aircraft. Participation by VFR pilots is voluntary.
Plain English
A radar service offered around certain busier airports where controllers line up arriving aircraft and keep them safely apart. IFR pilots get this service automatically; VFR pilots can choose to use it or not.
Context Anchor
You may see this term in the AIM, on charts, or hear it when talking to Approach Control near an airport with a Terminal Radar Service Area.
Derivation
TRSA stands for Terminal Radar Service Area. 'Terminal' refers to the airspace around an airport (where flights begin and end), and 'radar service' means controllers are tracking traffic on radar to help keep aircraft separated.
Why Pilots Care
Gives VFR pilots extra traffic spacing and sequencing that would otherwise be unavailable, reducing mid-air risk in busy terminal airspace.
Intuition Check
Do not read “service” here as vague customer help. In TRSA Service, it means a specific radar service from ATC: separation and sequencing for aircraft that are receiving it.
Example Sentence 1
Approaching the airport VFR, the pilot contacted approach control and accepted TRSA service for sequencing into the traffic pattern.
Example Sentence 2
Inside the TRSA, TRSA Service provided separation between the Cessna and a corporate jet on the same arrival path.