Aviation ABC
Explanation of important terms and abbreviations
Welcome to the world of aviation!
Kiss & ride, ETA or armed position: Are you familiar with all these expressions? There are many special terms and abbreviations that we use in aviation. Some of them you’ll hear quite often but maybe you’re not sure what they mean. We have collected them and provided explanations.
| Term | Explanation |
| ACG | Austro Control |
| ACMI | Aircraft, Crew, Maintenance and Insurance; a type of aircraft leasing (wet lease) |
| ADM | Airside Duty Manager; airport employee responsible for smooth airside operations on the apron |
| AFIS | Aerodrome Flight Information Service; airport information service for pilots |
| Airbus | European aircraft manufacturer |
| Airside | Area of an airport that is not open to the public and may only be entered after a security check, e.g. transit and apron area |
| Alternate | Alternate airport |
| Angle of attack | Angle at which the chord of an aircraft's wing meets the relative wind |
| Anti-skid surfacing | Special, very rough pavement on runways to increase friction and thus adhesion of aircraft tyres |
| AOC | Air Operator Certificate; permission to operate an aircraft |
| AOG | Aircraft on Ground; aircraft not ready to fly for technical reasons |
| Apron | Parking and handling area for aircraft in the security area of the airport |
| Apron | Aircraft parking area |
| APU | Auxiliary Power Unit of an aircraft for power supply on the ground |
| Armed position | Locking position for aircraft doors |
| Artificial horizon | Attitude indicator in the cockpit; replaces the natural horizon when it is not visible |
| ATC | Air Traffic Control |
| ATCO | Air Traffic Controller; directs air traffic; employed by Austro Control in Austria |
| ATIS | Automatic Terminal Information System; automatic information announcement about weather and airport data at airports with instrument flight traffic |
| Autopilot | Computer-based, fully automatic control of the aircraft |
| Avgas | Aviation fuel for aircraft with piston engines (= reciprocating engines) |
| Belly | Cargo hold under the passenger deck of an aircraft |
| Blackbox | Orange container for flight data recorder and voice recorder, which are used for accident investigation; "black box" because the containers are hermetically sealed as far as possible and have to withstand extreme conditions |
| Blacklist | List of airlines banned from taking off and landing in the EU |
| Boarding | Time period between asking passengers to proceed to the gate from which the aircraft can be accessed and the time when the aircraft doors are locked |
| Boarding completed | All passengers are on board |
| Boarding pass | Plane ticket authorising passengers to board an aircraft; in paper form or electronically on a mobile device |
| Boarding time | Time from which passengers can board the aircraft; not the departure time! |
| Briefing | Mandatory aircrew briefing for important procedures before and during a flight |
| Carrier | Airline that transports people or goods from point A to point B |
| CAT I, II, III a, b, c | See also ILS; categories for decision height in case of restricted visibility for landing approaches; Linz Airport has the best possible category with CAT IIIb with a decision height of less than 50 ft above ground and a runway visibility of at least 50 m |
| Charter flight | A non-scheduled, on-demand flight; the airline is contracted to transport people or goods to a specific destination on specific occasions for a client (e.g. tour operator) |
| Check-in | Process of registering a passenger and receiving the baggage for a flight; assigning the seat by issuing the boarding pass; also possible online |
| Checklist | List with instructions helping the cockpit crew to perform certain actions correctly and without forgetting anything |
| Clear air turbulence | Strong air movement in cloud-free air |
| Clearance | Approval of a flight plan |
| CRM | Crew Resource Management; distribution of tasks between the two pilots in the cockpit |
| Declaration | Declaration of goods subject to duty |
| Destination | Destination airport |
| Direct flight | Flight between two airports where stopovers are possible; not the same as a non-stop flight |
| Diversion / diverted | Diversion of an aircraft to another airport, e.g. for weather reasons |
| DME | Distance Measuring Equipment; used in the landing approach |
| Doors to arrival | Automatic release of the emergency slides in the aircraft doors is deactivated with this command in order to be able to open the aircraft doors |
| EASA | European Union Aviation Safety Agency |
| EFIS | Electronic Flight Instrument System; flight data display in the aircraft, colloquially also known as the board computer |
| ESTA | Electronic System for Travel Authorization for entry into the USA |
| ETA | Estimated Time of Arrival |
| ETOPS | Extended-range Twin-engine Operations Performance Standards; regulations that allow airlines to plan a shorter route for a flight than the standard safety rules allow to reach an alternate airport |
| FAA | US Federal Aviation Administration |
| Fan | Ducted fan used for propulsion |
| Fare | Air ticket fare |
| Filekey | Booking code; six-digit number code on an airline ticket used to identify the booking |
| Flaps | Landing flaps; increase lift during take-off or landing |
| Fly-by-wire | Aircraft commands sent to the control interfaces via electronic signals |
| Follow-me (vehicle) | Vehicle that guides the aircraft to its parking position |
| Foot (ft) | Unit of measurement in aviation (1 foot = 30.48 cm) |
| Galley | Aircraft kitchen |
| Gangway | Aircraft stairs or passenger boarding bridge |
| General Aviation Center | Centre through which private and (partly) commercial air traffic is handled |
| Go-around | An aborted landing of an aircraft that is on final approach or has already touched down |
| GPU | Ground Power Unit; mobile aggregate that supplies an aircraft with power on the ground |
| Ground handling | Services around the aircraft preparing it for the next departure |
| High loader | Aircraft loader used for picking up, transporting and precisely setting down heavy loads |
| Holding (pattern) | Manoeuvre flown by pilots awaiting further clearance |
| Hub | Transfer airport |
| IATA | International Air Transport Association |
| ICAO | International Civil Aviation Organization, which issues standards, rules and norms for civil aviation |
| ILS | Instrument Landing System; supports the pilot in the landing approach, especially in poor visibility; is divided into categories depending on the minimum required visibility; see Cat |
| In-flight entertainment | Umbrella term used for the entertainment options provided by electronic devices to passengers of a commercial aircraft during their flight |
| Infant | Children under two years of age who are not permitted to occupy their own seat on the aircraft |
| JET A-1 fuel | Special fuel for turbine-powered aircraft (kerosene) |
| Jet lag | Disturbance of the body's circadian rhythm after long-haul flights through several time zones |
| Jet stream | Strong air currents in the Earth's atmosphere of up to 500 kilometres per hour |
| Jumpseat | Fold-away seats in the cockpit or galley areas of an aircraft |
| Kiss & ride | Parking area for dropping off or picking up people in the immediate vicinity of the terminal |
| Knots | Measure of speed in aviation based on the nautical mile unit of length; one nautical mile (NM) corresponds to exactly 1,852 metres (1 knot = 1 NM/h = 1.852 km/h) |
| Landside | the area of an airport open to the public |
| Load factor | In air transport, the term seat load factor stands for the degree of utilisation of the aircraft; it can refer to both passengers and cargo |
| Long-haul flight | Flight lasting between six and twelve hours |
| Lost and found | The counter where you report the loss or damage of your luggage after arrival |
| Low-cost carrier | Low-cost airline that offers flights cheaper than classic airlines and forgoes comfort features |
| LOWL | ICAO code of Linz Airport; used to uniquely identify the aerodrome and is assigned by ICAO. |
| Marshaller | Flight Line Marshaller (FLM); ground personnel guiding the aircraft to its parking stand or to the runway |
| Mileage | Distance travelled during a flight/trip |
| Minimum connecting time | Minimum time required to reach a connecting flight |
| MTOW | Maximum Take Off Weight; maximum permitted take-off weight of an aircraft; the MTOW is also used as a parameter for calculating landing fees |
| Narrow-body | Narrow-body aircraft or standard fuselage aircraft; a commercial aircraft with only one cabin aisle and only up to six seats per row in economy class |
| No frills | Low-cost concept of low-cost airlines; savings are achieved by omitting special benefits and services |
| No-show | Passenger who, despite having made a booking, fails to board a flight without prior notice |
| Non-stop flight | Direct flight without stopover |
| NOTAM | Notice to Airman; short-notice and urgent instructions and information for the pilot that are important for an orderly, safe and smooth flight |
| NTSB | National Transportation Safety Board; US transport authority for the investigation of accidents in the transport sector |
| Off-blocks | Moment when an aircraft moves out of the parking position and prepares to taxi and take off |
| Open-jaw flight | an air journey in which the passenger does not fly back from the airport at which they arrived |
| OPS | Operations; preparation for the execution of the flight, including determining the most efficient route from point A to point B |
| PAX | Abbreviation for passenger and the colloquial term for an airline passenger |
| Pitot tube / pitot probe | L-shaped tube, open on one side, used to measure the speed of aircraft and helicopters |
| Preflight check | Inspection walk-through before flight operations and before each departure, in this case by the pilots |
| Priority | If a piece of luggage receives the "priority tag", it is unloaded and placed on the luggage conveyor belt first |
| Priority boarding | Service that can be booked with some airlines for an extra charge to be able to board the aircraft before the other passengers |
| Purser/purserette | Highest-ranking flight attendant in a cabin crew |
| Pushback | Pushing an aircraft backwards, as they cannot or are not allowed to taxi backwards under their own power |
| Ramp | Parking and handling area for aircraft in the security section of the airport |
| Roll-out | The first taxiing of a newly built aircraft out of the assembly hangar |
| Rush baggage | Baggage that may be transported without the associated passenger being on the same flight; usually baggage that has previously been loaded incorrectly |
| RVR | Runway Visual Range; measuring device for determining the visual range on the runway, indicated in feet or metres |
| Safety | Air traffic safety; includes operational safety to prevent air accidents through safety regulations, controls, and training |
| Seat load factor | Passenger load factor of an aircraft in percentages |
| Security | Airport security; in the field of civil aviation, refers to the defence against external threats |
| Sharklets | Term used at Airbus for the upward or downward curved extensions at the wingtips to improve environmental performance (fuel savings), as they reduce aerodynamic drag |
| SIGMET | Significant Meteorological Phenomena; weather warning in aviation |
| Skidometer | Special system (vehicle with trailer) with which the friction value on the runway can be determined; results are transmitted to the pilots by means of SNOWTAM |
| Slot | Time window for the take-offs and landings of aircraft |
| SNOWTAM | Special NOTAM informing pilots of the condition of the runway in winter |
| Stall | A reduction in the lift coefficient generated by a foil as the angle of attack increases |
| Stopover | Scheduled flight interruption of at least 24 hours |
| Taxiway | Taxiway for aircraft between apron and runway |
| Terminal | Area of an airport where passenger or cargo traffic is handled |
| TORA | Takeoff Run Available; sign at the junction of a taxiway with the runway indicating to pilots the maximum distance available before takeoff |
| Transit Area | Transfer area at international airports; no further entry formalities are required |
| UNMR (UM) | Unaccompanied Minor; child between the ages of 5 and 12 who is flying unaccompanied; a childcare service must be booked with the airline |
| UTC | Coordinated Universal Time; is used in aviation as a uniform time indication |
| VFR | Visual Flight Rules |
| Wide-body | Wide-body aircraft with a fuselage diameter of more than five metres and at least two aisles in the passenger cabin |
| Windshear | Strong change of wind direction within small areas (especially near thunderstorms) |
| Winglets | Upward or downward curved extensions at the wingtips to improve environmental performance (fuel savings), as they reduce aerodynamic drag |