ADS-B — what it is
ADS-B (Automatic Dependent Surveillance-Broadcast) is the standard transponder protocol for civilian aircraft and many military types. Public services (ADS-B Exchange, FlightRadar24) aggregate receiver-network data.
What it shows well
- Diplomatic and VIP movements (specific airframes are well-known).
- Airspace closures and reroutes.
- Patrol patterns of military airframes that broadcast.
- Cargo flights into and out of conflict-affected areas.
Limits
- Many military airframes do not broadcast ADS-B.
- Transponders can be disabled.
- Coverage is patchy over open ocean and parts of the global south.