Definition
A free service in the ADS-B system that uplinks traffic information to ADS-B In equipped aircraft. Ground stations use radar data from FAA surveillance sources to detect aircraft that are not transmitting ADS-B Out, and broadcast that traffic data to nearby ADS-B In equipped aircraft so the non-ADS-B traffic appears on the cockpit display.
Plain English
TIS-B fills in the picture of traffic around you. It takes radar information about aircraft that are not broadcasting their own ADS-B position and sends it up to your cockpit display, so you can see them too.
Context Anchor
You encounter TIS-B when using ADS-B In equipment or a cockpit traffic display that shows nearby aircraft.
Derivation
Broadcast means the ground station sends the traffic information out to all suitably equipped aircraft in the area, rather than to one specific aircraft. Anyone with the right receiver can pick it up.
Why Pilots Care
It extends traffic awareness to aircraft without ADS-B Out, improving situational awareness and collision avoidance in radar-covered airspace.
Intuition Check
Do not read “broadcast” as “everyone gets a complete traffic picture everywhere.” TIS-B depends on ground coverage, equipment, and whether the traffic source is being seen by the system.
Example Sentence 1
Thanks to TIS-B, the pilot could see a nearby aircraft on the cockpit display even though that aircraft was not equipped with ADS-B Out.
Example Sentence 2
TIS-B coverage allowed the flight crew to monitor nearby traffic while flying through Class B airspace.