Reference
Aviation glossary
Concise definitions for aviation terminology — from METAR and NOTAM to aerodynamics and airline operations. Search directly or scan alphabetically.
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IATAIATA (International Air Transport Association) is a trade association representing the world's airlines and setting global standards for operations, safety, ticketing, and baggage handling. IATA CodeA three-letter code assigned by the International Air Transport Association (IATA) to identify airports, cities, and airline stations on tickets, baggage tags, and booking systems for passenger-facing operations. ICAOThe International Civil Aviation Organization (ICAO) is the United Nations agency that sets global standards and regulations for civil aviation to ensure safety, efficiency, and consistency across all member countries. ICAO CodeA unique four-letter identifier assigned by the International Civil Aviation Organization to airports worldwide, used in flight plans, ATC communications, and aviation operations to precisely identify any airport on the planet. IcingIcing is the accumulation of frozen water on aircraft surfaces when flying through supercooled cloud droplets. It reduces lift, increases drag, and raises stall speed, creating a critical flight hazard. IFRInstrument Flight Rules (IFR) are regulations that govern flight when pilots navigate by cockpit instruments rather than visual reference to the ground, typically in low-visibility conditions. Indicated airspeedIndicated airspeed (IAS) is the aircraft's speed shown directly on the cockpit airspeed indicator, measured by comparing the pressure of incoming air against static atmospheric pressure. Induced DragInduced drag is the drag produced as a direct consequence of lift generation, created by wingtip vortices that form when high-pressure air beneath the wing escapes to the low-pressure region above it. Instrument Landing SystemInstrument Landing System (ILS) is a ground-based radio navigation system that provides precise lateral and vertical guidance to aircraft during low-visibility approaches, using a localizer and glide slope signal. Interline AgreementA commercial contract between airlines that allows them to accept each other's tickets, check baggage through to final destinations, and share revenue on a single itinerary. Interline connectivityInterline connectivity is the ability of airlines to cooperate on a single passenger ticket covering flights operated by two or more carriers, with automatic baggage transfers and unified rebooking protection. International Standard AtmosphereThe International Standard Atmosphere (ISA) is a standardized atmospheric model defining temperature, pressure, and density at every altitude as a universal reference for aircraft performance calculations. Isobaric ModeIsobaric mode is an aircraft oxygen system setting that automatically delivers a constant flow of oxygen when cabin altitude exceeds a preset pressure threshold, typically 8,000 to 10,000 feet.
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