Definition
Service B is a teletype-based aviation communications circuit operated within the National Airspace System, used to distribute flight plans, flight movement messages, and related air traffic service information between FAA facilities and authorized users.
Plain English
Service B is one of the FAA's behind-the-scenes messaging networks. It carries flight plans and flight-related messages between air traffic facilities so the system knows who is flying where.
Context Anchor
Seen in FAA acronym and NOTAM contraction lists, and occasionally in NOTAM or system-status text.
Why Pilots Care
Pilots don't use Service B directly, but their filed flight plans travel across it. When a flight plan is delayed, lost, or not showing up at a destination facility, Service B is often part of the path being checked.
Intuition Check
Do not read SVCB as “serviceable.” In FAA contractions, SVCB means “service B”; “serviceable” is a different idea.
Example Sentence 1
The flight plan was transmitted over Service B to the destination facility.
Example Sentence 2
Pilots check the SVCB listing to verify which support options remain active during their flight.