Automatic Dependent Surveillance-Broadcast (ADS-B) is a component of the Next-Generation (Next Gen) Air Transportation System. ADS-B is an advanced surveillance technology that combines an aircraft's positioning source (GPS), aircraft avionics, and a ground infrastructure to create an accurate surveillance interface between the aircraft & aircraft traffic control. ADS-B provides consistent position accuracy regardless of the aircraft's range from the receiver.
The improved accuracy and update rate of ADS-B is a critical segment of the NextGen infrastructure.
The FAA has determined that it will be necessary for all aircraft operating in specific airspaces to be equipped with ADS-B Out by 2020. A nationwide infrastructure of ground stations is scheduled for completion during 2013.
As of June 2010, only ADS-B Out is being mandated. ADS-B Out provides the ATC with real-time position information. ADS-B In is the aircraft's ability to receive and display other aircraft broadcasted information as well as the services provided by the ground stations.
ADS-B requires the use of a Positioning Source. As of June 2010, any positioning source is allowed; however, WAAS is the only positioning service that provides the equivalent availability required.
A Broadcast Link is also required for ADS-B functionality. There are two available options: 1090 MHz Extended Squitter (ES) or Universal Access Transceiver (UAT). FL 180 (the lower boundary of Class A airspace) is the ceiling for operating an aircraft equipped with UAT only.
ADS-B will eventually provide weather services, air traffic information, terrain maps and other flight information services for all pilots through satellite based data and ground stations. In accordance with NextGen, ADS-B will provide benefits that address some shortcomings over other, existing surveillance systems.
Some of these benefits include:
- Air-to-air surveillance capability
- Surveillance in remote areas where radar coverage is unavailable
- Real-time traffic information for aircraft not equipped with active traffic systems (ex. TCAS, TAS)
- Reduced separation between aircraft due to sharing of flight information between aircraft
- Better predictability in departure and arrival times
Ultimately, ADS-B will allow aircraft to fly at safe distances from each another.
to View the official FAA NextGen Final Rule released on 5/28/10.
You may also View an SEA Summary
of the FAA NextGen Final Rule (NOTE: this information has been altered for summary purposes and should be used as Reference Only).