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ADS-B (Automatic Dependent Surveillance-Broadcast)
A surveillance technology in which aircraft broadcast GPS-derived position and other data. ADS-B Out is required in much of controlled airspace; ADS-B In can deliver traffic and datalink weather that pilots use for strategic in-flight decisions, not close tactical maneuvering.
Related Terms
- AGL (Above Ground Level)A measurement of altitude expressed in feet above the terrain or ground directly below the aircraft. AGL is commonly used for traffic pattern altitudes and obstacle clearance.
- AileronA hinged flight control surface on the trailing edge of each wing that controls the aircraft's roll about its longitudinal axis. Moving the control yoke or stick left or right deflects the ailerons in opposite directions.
- AIRMET (Airmen's Meteorological Information)An in-flight weather advisory for conditions that may affect aircraft operations but are less severe than SIGMET criteria, such as moderate icing or turbulence, mountain obscuration, or widespread IFR. Modern briefings commonly present these as G-AIRMETs (graphical AIRMETs).
- AirspaceDefined areas of the atmosphere designated by the FAA with specific rules and requirements for aircraft operations. U.S. airspace is classified into Classes A, B, C, D, E, and G, each with different visibility, cloud clearance, and communication requirements.