Definition
A ground-based broadcast service, transmitted on the 978 MHz UAT (Universal Access Transceiver) datalink, that delivers aviation weather and aeronautical information to aircraft equipped with a compatible ADS-B In receiver. Products typically include METARs, TAFs, PIREPs, AIRMETs, SIGMETs, NEXRAD radar imagery, NOTAMs, TFRs, winds and temperatures aloft, and special use airspace status. The service is one-way (ground-to-air), free of charge, and available within line-of-sight coverage of FAA ground stations.
Plain English
A free service that uses ground transmitters to send weather maps, forecasts, and flight information up to aircraft that have the right receiver onboard. The pilot sees this information on a cockpit display.
Context Anchor
You will see FIS-B information on ADS-B In cockpit displays, panel avionics, or connected flight apps that can receive in-flight weather and flight information.
Derivation
The name describes the function directly: it broadcasts (one-way transmission to all listeners) flight information services to aircraft. The term mirrors TIS-B (Traffic Information Service Broadcast), its companion service that delivers traffic data over the same datalink.
Why Pilots Care
Gives pilots real-time access to weather and notices during flight, supporting better decisions without relying on voice requests.
Analogy
FIS-B is like a weather radio for equipped aircraft: it sends useful updates to anyone in range, but it is still your job to decide what the information means for your flight.
Grounding Statement
If your aircraft is in range of the service and has the right receiving equipment, FIS-B can place weather and flight information on your display while you are airborne.
Intuition Check
Do not assume “broadcast” means ATC is watching your specific flight or sending you a personalized warning. FIS-B is a one-way information feed for equipped receivers.
Example Sentence 1
On the cross-country flight, the pilot used FIS-B to monitor METARs along the route and confirm the destination weather was holding above VFR minimums.
Example Sentence 2
FIS-B provided the temporary flight restriction that affected the planned route.