#aviation

• Aerophilately — A specialized branch of philately dealing with the study and collection of special postage stamps (airmail stamps), labels, postmarks, and postal documents transmitted via air transport (airplanes, helicopters, zeppelins, or rockets). It tracks the evolution of postal rates and airways as well as aviation history reflected in documents.
• Airbrake — A mobile aerodynamic device (retractable lifting surface, flap, or spoiler) mounted on the wings or fuselage of an aircraft or space vehicle, designed to be deployed into the airflow in order to increase drag resistance and rapidly reduce movement speed.
• Airport terminal — The main building or complex of buildings located within an airport, specially designed and equipped with the necessary logistical infrastructure for passenger and aircrew services, check-in and boarding formalities, security control, baggage sorting, and air transport flow management.
• Aeromaritime — Relating simultaneously to airspace and maritime space; combining aeronautical and naval elements or taking place over seas and oceans. The term commonly describes mixed transport lines, coastal patrol and rescue missions, combined military exercises, or logistical infrastructures connecting ports and airports.
• Aviation medicine — A specialized, interdisciplinary branch of medicine that studies the physiological, psychological, and pathological effects exerted by high-altitude flight and variations in altitude or barometric pressure on the human body. This discipline establishes medical selection criteria, fitness standards for pilots, and emergency assistance during air transport.
• Model aircraft — A small-scale aircraft built as a miniature replica of a real plane or based on an original design, capable or incapable of flight, used for sporting, recreational, educational, or experimental purposes. Flight-capable model aircraft can be radio-controlled, control-line operated, or free-flying, and are built from lightweight materials such as balsa wood, polystyrene, or carbon fiber.
• Aeromodelling — A practical sporting-technical activity or hobby consisting of designing, building, tuning, and flying model aircraft. As an official sporting discipline governed by the World Air Sports Federation (FAI), aeromodelling includes national and international competitions organized across various aircraft classes (free flight, control-line, radio-controlled, or scale replicas).
• Aeromodeller — A person who practices aeromodelling as a hobby, technical sport, or research activity; a specialist or enthusiast who designs, builds, adjusts, and flies scale model aircrafts (airplanes, gliders, helicopters). This activity involves applying advanced knowledge of aerodynamics, precision mechanics, electronics, and using lightweight composite materials to achieve optimal stability and high flight performance.
• Female aeromodeller — A woman who practices aeromodelling; an enthusiast or competitive athlete specialized in assembling, structurally calibrating, and radio-controlling scale model aircraft. Her activity combines the engineering rigor of construction with the fine reflex skills required to pilot the devices during technical demonstrations or specialized championships.
• Aeronaut — A specialized or authorized person who navigates through the atmosphere using an aerostat, an airship, or a balloon; a pilot or member of the flight crew operating an aircraft lighter than air. In a historical sense, the term designates the pioneers of atmospheric flights who paved the way for airspace exploration.
• Female aeronaut — A woman specialized in aerial navigation, who pilots or belongs to the flight crew of an aerostat, balloon, or airship. The term highlights the female contribution to the development of atmospheric navigation, including both the daring women from the pioneering era of aerostation and modern female specialists in lighter-than-air flight.
• Aeronautical — Belonging to aeronautics or relating to aerial navigation, as well as the study, design, construction, and operation of aircraft. This term describes structural, regulatory, industrial, or scientific elements essential for vehicle flight within Earth's atmosphere, ranging from airplanes and helicopters to complex propulsion and control systems.
• Aeronautics — The science, technology, and collective industries dealing with the design, construction, testing, operation, and navigation of aircraft within Earth's atmosphere. The field encompasses complex disciplines such as aerodynamics, aerospace structures, propulsion, and avionics systems, aiming to optimize the safe movement of vehicles lighter or heavier than air.
• Aircraft — Any technical apparatus capable of sustaining itself in the atmosphere and moving through airspace due to the reactions of the air, other than its reactions against the earth's surface. This vast category structurally includes both aircraft lighter than air, such as balloons and airships, and aircraft heavier than air, such as airplanes, helicopters, and gliders.
• Aeronaval — Belonging simultaneously to aviation and the navy, or intended for joint tactical operations executed by air and maritime forces. The term applies to logistical bases, complex tactical exercises, combined radar technologies, or large vessels (such as aircraft carriers) structurally designed to launch and recover aircraft at sea.
• Aircrew member — A person belonging to the flight or cabin crew of an aircraft during flight, performing professional activities in the air; a pilot, co-pilot, navigator, flight engineer, or flight attendant. As an adjective, it describes the personnel, activities, or specific medical aptitudes required for performing duty aboard airplanes.
• Air navigation — The science, technology, or practical activity of guiding an aircraft safely along a determined route between two specific geographic points. This complex field includes trajectory planning, exact position determination through astronomical, radio, or satellite methods, as well as constant interaction with air traffic management systems and meteorological services.
• Aeropathy — A general medical term used to designate any pathological condition, organic affection, or physiological disorder directly caused by sudden atmospheric pressure variations, abnormal chemical composition of inhaled air, or high-altitude exposure. This clinical category structurally includes decompression sickness in divers and pilots, altitude hypoxia, and barotrauma.
• Aeropause — A transition zone or upper region of Earth's atmosphere, located beyond the dense layers, where the air density becomes so low that it can no longer provide lift for conventional aircraft or support sound wave propagation. This structural threshold marks the functional limit of classical aviation and the beginning of upper aerospace, where flight is governed exclusively by orbital mechanics.
• Aeroplane — A historical or archaic name given to early generation airplanes; a flying machine heavier than air, propelled by an engine and sustained in the atmosphere by the lift force of fixed wings. Although almost completely replaced by 'avion' in modern technical language, it retains strong documentary and literary value linked to aviation pioneering.