Definition
A free ground-based service, provided as part of the FAA's ADS-B system, that uplinks traffic information to suitably equipped aircraft. TIS-B takes radar-tracked traffic data from FAA ground surveillance sources and broadcasts it to ADS-B In receivers, allowing pilots to see nearby aircraft on a cockpit display—including aircraft that are not themselves transmitting ADS-B Out.
Plain English
A service that beams traffic data up from ground stations to your cockpit display, so you can see other aircraft around you, even ones that aren't sending out their own position signals.
Context Anchor
You may see Traffic Information Service–Broadcast on an ADS-B traffic display, portable flight app, or installed cockpit screen when flying in areas covered by the service.
Derivation
Broadcast originally meant spreading seed widely over the ground. In radio and data systems, it means sending information outward for receivers to pick up. That fits this term because traffic information is sent out from the ground to aircraft that are equipped to receive it.
Why Pilots Care
It improves situational awareness of nearby traffic and helps avoid conflicts, especially when other aircraft are not broadcasting their own position data.
Grounding Statement
The service takes traffic information known on the ground and sends it up to equipped aircraft nearby.
Intuition Check
Do not assume Traffic Information Service–Broadcast shows every aircraft around you. It is an aid to awareness, not a guarantee that all traffic is displayed or that separation is being provided.
Example Sentence 1
With ADS-B In installed, the pilot received Traffic Information Service–Broadcast data showing nearby traffic on the cockpit display.
Example Sentence 2
Even without direct ADS-B signals from nearby planes, Traffic Information Service–Broadcast provided useful traffic information during the approach.