Plain English Meaning
A service that uses ground radar to send a picture of nearby aircraft up to your cockpit so you can see where other traffic is and avoid it.
Full Definition
A ground-based air traffic surveillance service that uses radar data to send nearby traffic information directly to suitably equipped aircraft via a Mode S data link. The information appears on a cockpit display and shows the position, altitude, and movement of other transponder-equipped aircraft within a defined range, helping the pilot maintain visual separation.
Context Anchor
Seen in avionics manuals, traffic display descriptions, and discussions of electronic traffic awareness in radar-covered areas.
Why Pilots Care
Gives pilots early awareness of nearby traffic so they can spot and avoid other aircraft before a conflict develops.
Intuition Check
Do not read “service” as a guarantee that all traffic is being watched for you. Traffic Information Service is advisory only; it helps awareness but does not replace the pilot’s responsibility to see and avoid other aircraft.
Example Sentence 1
With TIS active on the Mode S transponder, the pilot saw a target two miles ahead and 500 feet below before spotting it visually.
Example Sentence 2
While on approach in marginal weather, the Traffic Information Service helped locate a slower aircraft on the same route.