Search Terms | Read Rules
 

 

 
Everywhere
  Term's Names
  Term's Descriptions
Maverick Jets is without a doubt
the most dynamic aircraft in it's class. From ground-breaking innovations in engineering to hand-crafted luxurious interiors, our flagship "Leader" is set far apart from competing personal jets yet surprisingly affordable.
Visit our site for perfomance / specs, press releases, purchasing options, photos and video of the "Leader".
Visit us now

 
Site Map


Directory
About Us
Links

0FUELWT Zero (0) Fuel Weight.
360, 540 AND OTHER NUMBERS Degrees in arc. 360 signifies one full turn through an axis. A 360 turn is a flat turn; where the aircraft does not roll its wings but instead just sl...
3D Flight pattern noted by performance of particular aerobatics below an airplane.
3F Informal reference for flip flop flying. Similar to 3D, except not as smooth.
A Aircraft (JAR - FCL License)
A/C Air conditioner Unit
A/G Aircraft. Air Craft
A/T Automatic throttle.
AAIM Aircraft Autonomous Integrity Monitor
ABAS Aircraft Based Augmenting System.
ABC Aluminum-Brass-Chrome. Three main components used in the production of engines that do not have rings. Engines with aluminum piston, chrome or nickel ...
ABL Advanced Bimetallic Liner. A Specialized form of ABN. Instead of a single-material plating,single-step, the ABL Plating process is based on a layered ...
ABN Aluminum-Brass-Nickel. The components used in the production of non-ringed engines. These engines use an aluminum piston, and a nickel plated brass sl...
ABOVE GROUND LEVEL (AGL). Distance between the aircraft and the ground Synonyms: radar altitude;
ABSOLUTE Fixed reference, as opposed to moving reference.
AC Advisory circular
ACARS Airline Communication and Reporting System.
ACAS Airborne Collision Avoidance System
ACC Area Control Center.
ACCELARATION Rate of change of velocity, either scalar or vector, often with subscripts such as ENU or XYZ to denote the coordinate frame; time derivative of veloc...
ACCELERATION EAST Aircraft acceleration in true east direction; Symbols: A sub E; Typical Units: ft/s-squared; Dimensions: Length / Time-squared;
ACCELERATION NORTH Aircraft acceleration in true north direction; Symbols: A sub N; Typical Units: ft/s-squared; Dimensions: Length / Time-squared;
ACCELEROMETER An inertial device for measuring acceleration, usually in three orthogonal axes (lateral X, longitudinal Y, and vertical Z); accelerometers usually co...
ACCEPT To allow to proceed, for example with a position update, usually by an operator; Compare: reject
ACCIDENT Occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of flight...
ACCURACY Measure of exactness, possibly expressed in percent; Compare: precision
ACG ATM/CNS Consulting Group (Euro control)
ACI Airport Council International
ACQUIRE To begin reception of useful data
ACT active, activated, activation message
ACTIVATE To begin performing a mission objective, such as flying along a radial of a radio station; usually refers to a mode of radio navigation, such flying a...
AD Directive; Maintenance or modification ordered by FAA.
ADB Aerodrome
ADC Air Data Computer
ADCUS Advise customs
ADD Architecture Description Document
ADDR Air data computer
ADF Automatic Direction Finder
ADI Attitude direction indicator
ADIZ Automatic Direction Finder
ADLP Airborne Data Link Processor
ADMINISTRATOR means the Federal Aviation Administrator or any person to whom he has delegated his authority in the matter concerned
ADS Automatic dependent surveillance
ADS-A Automatic Dependent Surveillance
ADS-B Automatic Dependent Surveillance-Broadcast
ADS-C Automatic Dependent Surveillance-Contract
ADVERSE YAW Yaw generated when the ailerons are used. The lifting wing generates more drag, causing the plane to yaw toward it.
ADVISORY Automatic Direction Finding
AEA Association of European Airlines
AECMA Association of European Aerospace Industries
AEROBATICS Acrobatic or stunt maneuvers in the air such as loops, rolls, and others.
AERODYNAMIC COEFFICENTS means non-dimensional coefficients for aerodynamic forces and moments
AES Aircraft Earth station
AFB Air Force Base
AFCS Automatic flight control system
AFD Adaptive flight displays
AFDS Autopilot flight director system
AFIS Automated flight information system (AlliedSignal)
AFM Airplane Flight Manual
AFT Towards the rear. Used such as: "...with an aft center of gravity...."
AFTER RUN OIL A lubricant designed to displace unburned fuel in the engine after running. The fuel can accelerate corrosion on some engine parts. By using an after ...
AFTN Aeronautical Fixed Telecommunication Network
AGA Aerodromes and Ground Aids (AIP)
AGATE Advanced General Aviation Transport Experiments (NASA)
AGDL Air-Ground Data Link
AGL Above Ground Level. Used in reference to altitude, e.g. 5000 ft AGL. See also MSL.
AGLO Above Ground Level
AGR Automatic flight control Sys.
AGR SLANT RANGE Straight-line distance from the aircraft to a point on the ground;
AHOV Approach to hover
AHRS Attitude-heading reference system.
AI Altitude indicator
AIC Aeronautical Information Circular
AIDING A process by which one or more sensors provide data to another sensor to produce results better than any single sensor; aiding occurs at the data sour...
AILERON A control surface on fixed-wing aircraft, usually mounted on the aft edge of wings, that controls roll, and is controlled by the wheel; Symbols: delta...
AILERONS Hinged control surfaces on usually the wing which can change the wing`s lifting properties. Often located near the tips. Used to bank the aircraft. Th...
AIM ATFM Information Message
AIM (AIRMANS` INFORMATION MANUAL) A primary FAA publication whose purpose is to instruct airmen about operating in the US airspace system.
AIP Aeronautical Information Publication
AIR CARRIER Person who undertakes directly, by lease, or other arrangement, to engage in air transportation.
AIR DATA Values computed from pitot, static and temperature measurements, usually by means of a digital computer; ARINC 575 defines outputs.
AIR DATA COMPUTER (ADC) A primary navigation data source. A navigation sensor based on atmospheric data sensors; usually measures static pressure, dynamic pressure, and outsi...
AIR DATA DEAD RECKONING (ADDR) Dead reckoning navigation based on simple instruments as source (barometric altimeter, magnetic compass, airspeed indicator, known wind conditions); s...
AIR DEFENSE IDENTIFICATION ZONE(ADIZ) The area of airspace over land or water, extending upward from the surface, within which the ready identification, the location, and the control of ai...
AIR GROUND RANGING (AGR) Straight-line distance from the aircraft to a point on the ground;
AIR ROUTE TRAFFIC CONTROL CENTER(ARTCC) OR CENTER Facility established to provide air traffic control service to aircraft operating on IFR flight plans within controlled airspace and principally durin...
AIR TAXI An aircraft operator who conducts operations for hire or compensation in accordance with FAR Part 135 in an aircraft with 30 or fewer passenger seats ...
AIR TRAFFIC means aircraft operating in the air or on an airport surface, exclusive of loading ramps and parking areas
AIR TRAFFIC CLEARANCE means an authorization by air traffic control, for the purpose of preventing collision between known aircraft, for an aircraft to proceed under specif...
AIR TRAFFIC CONTROL means a service operated by appropriate authority to promote the safe, orderly, and expeditious flow of air traffic
AIR TRAFFIC CONTROL (ATC) A service operated by the appropriate authority to promote the safe, orderly, and expeditious flow of air traffic.
AIR TRAFFIC CONTROL (ATC). Standard aviation term
AIR TRANSPORTATION means interstate, overseas, or foreign air transportation or the transportation of mail by aircraft. Alert Area. An alert area is established to infor...
AIR-MASS FLIGHT PATH ANGLE Angle in vertical plane of earth speed vector and groundspeed vector; occasional definition for flight path angle; Compare: earth-referenced flight pa...
AIRAC Aeronautical Information Regulation and Control
AIRBORNE GROCER A device for barrage-jamming of Wurzburgs. Extremely vulnerable to being homed onto.
AIRCRAFT means a device that is used or intended to be used for flight in the air
AIRCRAFT (AC) A craft that flies in the air; either fixed or rotary wing.
AIRCRAFT ENGING means an engine that is used or intended to be used for propelling aircraft. It includes turbo superchargers, appurtenances, and accessories necessary...
AIRFOIL The shape of the wing when looking at its profile. Usually a raindrop type shape.
AIRFRAME means the fuselage, booms, nacelles, cowlings, fairings, airfoil surfaces (including rotors but excluding propellers and rotating airfoils of engines)...
AIRPLANE means an engine-driven fixed-wing aircraft heavier than air, that is supported in flight by the dynamic reaction of the air against its wings
AIRPORT An area on land or water that is used or intended to be used for the landing and takeoff of aircraft and includes its buildings and facilities, if any...
AIRPORT TRAFFIC CONTROL TOWER(ATCT) A terminal facility that uses air/ground communications, visual signaling, and other devices to provide ATC services to aircraft operating in the vici...
AIRSHIP means an engine-driven lighter-than-air aircraft that can be steered
AIRSPEED The speed of an aircraft relative to its surrounding air mass. See: calibrated airspeed; indicated airspeed; true airspeed.
AIRSPEED (AS, A/S) See Also: state data, true airspeed, indicated airspeed, calibrated airspeed; Symbols: V sub A/S; Typical Units: kt, ft/s; Dimensions: Length / Time;
AIRSPEED INDICATOR An onboard instrument which registers velocity through the air, in miles per hour or in knots.
AIRY A standard model for computing earth data
AIS Aeronautical Information Service
ALIGHNMENT A basic control to a data source from controls and displays to align a device. Also a procedure to align physical devices, usually navigation sensors,...
ALL-WEATHER FIGHTER/INTERCEPTOR -equipped jet fighter airplane which can operate at night or in the worst weather.
ALS approach light system.
ALT Altitude
ALTERNATE AIRPORT means an airport at which an aircraft may land if a landing at the intended airport becomes inadvisable
ALTIDUTE GAIN (KALTINT) A guidance control law parameter, generated by the vertical guidance modes; varies control authority of the altitude integral in vertical guidance, to...
ALTIMETER An onboard instrument which senses air pressure in order to gauge altitude.
ALTIMETER SETTING The barometric pressure reading used to adjust a pressure altimeter for variations in existing atmospheric pressure or to the standard altimeter setti...
ALTINTVAL Altitude integral input
ALTITUDE Height, usually with respect to the terrain below (radar altitude, feet above closest dirt) or fixed earth reference (barometric altitude, feet above ...
ALTITUDE ENGINE means a reciprocating aircraft engine having a rated takeoff power that is producible from sea level to an established higher altitude
ALTITUDE ERROR A basic output from guidance to flight director, indicating the difference between actual altitude and desired altitude; Symbols: DELTA h; Typical Uni...
ALTITUDE ERROR SCALE FACTOR(KZSF) A guidance control law parameter, generated by the vertical guidance modes; varies control authority of vertical guidance
ALTITUDE INTEGRAL INPUT (ALTINTVAL). A guidance control law parameter, generated by the vertical guidance modes; a reference altitude for reducing steady-state errors in altitude error Ty...
ALTITUDE INTEGRAL LIMIT (INTMAGLIM). A guidance control law parameter, generated by the vertical guidance modes; limits the magnitude of altitude integral value Typical Units: ft; Dimensi...
ALTN Alternate
ALTP Airline Transport Pilot`s License)
AM Amplitude modulation
AMC Acceptable Means of Compliance
AME Aviation Medical Examiner (U.S.)
AMIE AIS Met Information Equipment (Swiss Computer Self Briefing System)
AMLCD Active-matrix liquid crystal display.
AMPHIBIAN An aircraft that can fly off of water or land. The wheels retract into the hull or floats, depending upon the type of aircraft. An amphibian can land ...
AMS Aero Medical Services
AMSL Above mean sea level
ANGEL OF ATTACK The difference between pitch and the air-referenced flight path angle; the angle between the aircraft center line and the airspeed vector in the verti...
ANGEL OF ATTACK (AOA) The angle between the chord line of the wing of an aircraft and the relative wind.
ANGLE OF ATTACK The angle that the wing penetrates the air. As the angle of attack increases so does lift, up to a point (and drag).
ANGULAR ACCELERATION Rate of change of angular velocity, either scalar or vector, often with subscripts such as XYZ to denote the coordinate frame; time derivative of angu...
ANGULAR POSITION Amount of rotation about an axis, either scalar or vector, often with subscripts such as XYZ to denote the coordinate frame; time integral of angular ...
ANGULAR VELOCITY Rate of change of rotation about an axis, either scalar or vector, often with subscripts such as XYZ to denote the coordinate frame; time derivative o...
ANM ATFM Notification Message
ANNUAL Mandatory inspection of airframe and power plant that occurs every 12 months.
ANNUNCIATOR Any one of warning, caution, or advisory; Synonyms: alert;
ANR Air Navigation Routes
ANS Active Noise System
ANSP Air Navigation Services
ANT Airspace Navigation Team (Euro control)
AO Aircraft Operator
AOC Airline Operations Centre
AOPA Aircraft Owners and Pilots Association
AOR Aero of Responsibility
AOWIR Aircraft Operator What-If Reroute (CFMU/IFPS)
AP Auto Pilot
APERIODIC A process that executes based on events rather than a fixed rate, it is not synchronized to other processes of interest; Compare: periodic;
APP Approach (Control)
APPLIANCE means any instrument, mechanism, equipment, part, apparatus, appurtenance, or accessory, including communications equipment, that is used or intended ...
APPR Approach
APPROACH (APPR) To fly towards a point; a basic guidance mode, providing lateral guidance, longitudinal guidance, and vertical guidance to a point at an operator sele...
APPROACH SPEED The recommended speed contained in aircraft manuals used by pilots when making an approach to landing. This speed will vary for different segments of ...
APPROACH TO HOVER (AHOV) Hover approach of a rotary wing aircraft.
APPROVED unless used with reference to another person, means approved by the Administrator
APR Auxiliary Power Reserve
APRON A defined area on an airport or heliport intended to accommodate aircraft for purposes of loading or unloading passengers or cargo, refueling, parking...
APU Auxiliary power unit
ARCID Aircraft Identification
AREA The number of square inches (or feet) of the wing. It`s the wingspan multiplied by the wing`s chord. The area of a tapered wing is the wingspan multip...
AREA NAVIGATION (RNAV) means a method of navigation that permits aircraft operations on any desired course within the coverage of station-referenced navigation signals or wi...
AREA NAVIGATION LOW ROUTE means an area navigation route within the airspace extending upward from 1,200 feet above the surface of the earth to, but not including, 18,000 feet ...
AREA NAVIGATION ROUTE means an area navigation route within the airspace extending upward from, and including, 18,000 feet MSL to flight level 450
ARF Almost Ready to Fly. A prefabricated aircraft.
ARINC Aeronautical Radio, Inc. A nonprofit corporation owned by member airlines to define form, fit, and function of avionics equipment and to provide radio...
ARINC 419 Digital information transfer characteristics as applied in ARINC 500-series equipment specifications.
ARINC 547 Digital specification for ILS reference sensors.
ARINC 561 Inertial navigation system specifications.
ARINC 568 Inertial sensor DME reference specification.
ARINC 571 Inertial sensor attitude-heading reference system specifications.
ARINC 575 Digital air-data system specifications.
ARINC 700-SERIES All-digital equipment specifications for new-generation transport category aircraft.
ARINC 743 All-digital specifications for FANS-1 compatibility.
ARM To strive for a mission objective, such as flying toward a radial of a radio station; usually refers to a mode of radio navigation, such as striving t...
ARMED FORCES means the Army, Navy, Air Force, Marine Corps, and Coast Guard, including their regular and reserve components and members serving without component s...
ARN ATS Route Network
ARNS Aeronautical Radio Navigation Services
ARO Air Traffic Services Reporting Office (or Airport Reporting Office)
ARP Airport Reference Point
ARR Arrival
ASA Auto land status annunciator.
ASAP As soon as possible
ASAS Airborne Separation Assurance system
ASCB Avionics standard communication bus (Honeywell)
ASDIC :, (Allied Submarine Investigation Committee), a ship-borne sonic detection system first developed in 1917.
ASF Air Safety Foundation (AOPA-USA)
ASL Above sea level
ASM Air Space Management
ASPECT RATIO The wingspan divided by the chord. Aspect ratio is important where a wing`s efficiency is concerned. A short aspect ratio (short wings) is better for ...
ASPH Asphalt Runway
ASPIDISTRA Codename for the ground transmitters operating the DARTBOARD interference system
ASR means airport surveillance radar.
ASTRONOMICAL LATITUDE Latitude measured with respect to vector of apparent gravity; Compare: geocentric latitude, geodetic latitude; Symbols: Phi sub A; Typical Units: rad,...
ASV Air to Surface Vessel. An airborne or ship borne radar used to detect surfaced U-boats and other surface vessels.
ATA Actual Time of Arrival
ATC Air Traffic Control. A service operated by appropriate authority to promote the safe, orderly and expeditious flow of air traffic.
ATCO Air Traffic Control
ATD Actual Time of Departure
ATE Actual Time Enroute
ATFM Air Traffic Flow Management
ATI AND ATR ARINC form factors.
ATIR Air Traffic Incident Report ("Near-Miss Report")
ATIS Automatic Terminal Information Service
ATM Air traffic management.
ATMOSPHERIC DATA Air Traffic Control
ATN Air Traffic Management
ATP Airline Transport Pilot (the "highest" grade of pilot certificate)
ATPL Airline Transport Pilot (`s License)
ATS Air Traffic Services
ATSP Air Traffic Service Provider
ATTIDUDE HEADING REFERENCE SYSTEM(AHRS) Combines information from a Magnetic Heading Sensor with self-contained aircraft acceleration data to provide attitude, heading, position, body inerti...
ATTITUDE The primary aircraft angles in the state vector; pitch, roll, and yaw;
ATTITUDE INDICATOR A vacuum powered instrument which displays pitch and roll movement about the lateral and longitudinal axes.
ATV Adjustable Travel Volume. Used on many radio transmitters to limit, or extend, maximum throw of a servo. ATV can indicate having a single adjustment w...
AUDIO PANEL Electronic device used to switch between radios.
AUFKL„RUNG Reconnaissance
AUSTRALIAN NATIONAL A standard model for computing earth data
AUTOGYRO An aircraft equipped with a rotating wing, or rotor, to sustain itself in the air, and a propeller to move forward.
AUTOMATIC DIRECTION FINDING(ADF) A basic guidance mode, providing lateral guidance to a radio station. Equipment that determines bearing to a radio station;
AUTOMATIC FLIGHT CONTROL SYSTEM(AFCS) An automated system for controlling the primary flight controls, often with built-in functions for guidance and flight director, and sometimes radio n...
AUTOMATIC TERMINAL INFORMATIONSERVICE (ATIS) The continuous broadcast of recorded non control information in selected terminal areas. Its purpose is to improve controller effectiveness and to rel...
AUTOPILOT A method of an automatic flight control system which controls primary flight controls to meet specific mission requirments,I.E. maintain a heading or ...
AUTOROTATION means a rotorcraft flight condition in which the lifting rotor is driven entirely by action of the air when the rotorcraft is in motion
AUX FUEL Auxiliary fuel tanks.
AUXILIARY ROTER means a rotor that serves either to counteract the effect of the main rotor torque on a rotorcraft or to maneuver the rotorcraft about one or more of ...
AVERAGING FILTER A filter for combining multiple data sources, usually of the same type, by adding with weighted averages; a simple average of the data sources; Compar...
AVGAS Aviation Gasoline (piston aircraft fuel)
AVM Avionics monitor
AWACS Airborne Warning And Control System. An electronically very souped-up Boeing 707. (Pronounced "AY-wax.")
AWY Airway
AXIS The line around which a body rotates.
AZIMUTH An angle in the horizontal plane, usually measured with respect to body coordinates
B Airspace ICAO Class B
BABLW Bundesamt fìr Betriebe der Luftwaffe
BACKLASH Term describing the amount of play between gears, or gear mesh. If too loose, the gear can slip, or strip the teeth. Too tight, and excessive wear is ...
BALL LINK Connection using a ball, and a link which rotates on the ball. Used to connect the servo to a control surface or lever.
BALT SEL Barometric altitude select
BAND-PASS FILTER (BPF). A filter that allows frequencies between two cutoff frequencies to pass while attenuating frequencies outside the cutoff frequencies; a band-pass filt...
BANK ANGLE The angle between the horizontal plane and the right wing in the lateral plane, positive when the right wing is down; Synonyms: roll; Symbols: phi, Ph...
BARN DOOR AILERONS Larger, built up ailerons rather than an aileron from a simple strip of solid wood like some kits have.
BARNSTORMER A pilot who, in the early years of aviation, gave airplane rides to people and performed aerobatics for a fee.
BAROMETRIC ALTITDUDE SELECT(BALT SEL) A basic guidance mode, providing vertical guidance to an operator selected barometric altitude;
BAROMETRIC ALTITUDE Height with respect to fixed earth reference (above mean sea level); Synonyms: pressure altitude; Symbols: h sub b; Typical Units: ft; Dimensions: Len...
BAROMETRIC PRESSURE Height with respect to fixed earth reference (barometric altitude, feet above mean sea level); Synonyms: pressure; Symbols: p sub a; Typical Units: in...
BASE LOAD ANTENNA A rigid, short antenna mounted to the aircraft. Used to replace the longer receiver antenna.
BASIC OPERATING WEIGHT (BOW) Empty weight typically equipped + unusable fuel and trapped liquids + 2 pilots (400 lbs.) + supplies.
BAZL Bundesamt fìr Zivilluftfahrt (Swiss CAA)
BBJ Boeing Business Jet
BC Bus controller
BCD Binary coded decimal.
BDY Boundary
BEACON A device, usually based on the ground, that aids in determining position or direction;
BEAM WIDTH The included angel of a weather radar interrogation signal.
BEARING (BRG). Direction on a compass; Synonyms: direction; Symbols: B; Typical Units: rad, deg;
BEF Before
BENDIX Avionics mfgr.
BESSEL 1841 A standard model for computing earth data
BFR Biennial Flight Review (USA)
BFU Bìro fìr Flugunfalluntersuchungen
BIAS An offset applied to a measurement for error correction; Synonyms: offset
BIG BEN North Sea patrols undertaken by Bomber Command to try to detect the guidance system of the German V2 rockets.
BIG WING A plan espoused by DRS Bader during the Battle of Britain. A tactic to use five or more fighter squadrons together. The plan was not workable until af...
BINDING What occurs when the friction at a joint is stronger than the linkage.
BIS Built-in simulation
BITE Built-in test equipment.
BLACK THURSDAY August 15th 1940. The day on which the Luftwaffe took at least 90 losses.
BLADE BALANCER Usually called a "prop balancer" for aircraft. Used to ensure that the propeller and spinner are equally balanced side-to-side to avoid vibration prob...
BLEED AIR High pressure air ducted from engine to pressurize cabin and other uses.
BLITZKRIEG A tactic of aerial artillery in support of fast-moving armor. The term was inaccurately applied to the bombing of London and other British cities in 1...
BLONDE An automatic camera which provided continuous record of signals within a specified band, as received by a cathode ray tube.
BODY The aircraft, usually referring to a coordinate system;
BODY COORDINATES Coordinates referenced to the body of the aircraft; See Also: XYZ; Compare: earth coordinates, stability coordinates
BOEING The Boeing Company, with headquarters in Seattle, Washington, U.S., one of the nation`s largest exporters. The company is a major U.S. government cont...
BOOTS Inflatable device on leading edge of wings and tail. Used to remove ice.
BOOZER RAF airborne device which warned that the aircraft carrying it was being monitored by Wìrzburg
BORESIGHT ANGLE The angle between the center line of a sensor and aircraft center line, either by design or by misalignment;
BORESIGHTING A basic control to a data source from controls and displays to bore sight a device; Also, a procedure to align the center line of physical devices, us...
BORING HOLES IN THE SKY Having fun flying an R/C airplane, without any pre-determined flight pattern.
BPF Band-pass filter
BRACING WIRE A solid steel wire used to support the structure of an airplane`s wings or fuselage.
BRAKE HORSEPOWER means the power delivered at the propeller shaft (main drive or main output) of an aircraft engine
BRG Bearing
BRIAR A ground transmitter operating in the 300-600 MHz band used to jam enemy Wìrzburg ground receivers.
BRNAV Basic RNAV (RNP-5 compliant)
BSE Bovine Spongiform Encephalopathy (or: mad cow disease)
BSU Beam steering unit.
BUDDY OR TRAINER BOX Two similar transmitters that are wired together with a "trainer chord." This is most useful when learning to fly -- it`s the same as having dual cont...
BUILT-IN SIMULATION (BIS) Function in avionics software that simulates sensors, aircraft, and pilot, to exercise avionics software (including navigation, radio navigation, guid...
BUS CONTOLLER (BC). Term defining role of device on a MIL-STD-1553 bus as being master; Compare: remote terminal;
C Airspace ICAO Class C
C(-OFFICE) Crew Office (AIS/MET)
C/R Counter-rotating propellers.
CA Abbreviation for cyanoacrylate. An instant type glue that is available in various viscosities (Thin, Medium, Thick, and Gel). These glues are ideal fo...
CAA Civil Aviation Authority (of a country)
CAB Civilian Aviation Board.
CABIN PRESSURIZING A mechanism used to maintain air pressure in an airplane`s sealed cabin at a level suitable for passengers.
CALIBRATED AIRSPEED Calibrated airspeed is equal to true airspeed in standard atmosphere at sea level.
CALIBRATED AIRSPEED (CAS) The indicated airspeed of an aircraft, corrected for position and instrument error. Calibrated airspeed is equal to true airspeed in standard atmosphe...
CALIBRATION A basic control to a data source from controls and displays for calibrating a device; Also, a procedure to adjust physical devices so that they provid...
CAMBER If you draw a line through the center of the airfoil that`s exactly half-way between the top and bottom surface, you get the mean airfoil line. Depend...
CANARD The horizontal surface forward of the wing used to control pitch. It`s found on very few aircraft. Also the word used to describe aircraft that have a...
CANT ANGLE Angle of nacelle mounting; Typical Units: rad, deg;
CAPS Complete Aircraft Parachute System
CAPTURE To attain an objective, such as reaching a radial of a radio station; See Also: capture criterion; Compare: activate, arm;
CAPTURE ITERATION A test case to determine if an armed objective has been captured; In avionics, an aircraft might have an objective to fly to a radial of a radio stati...
CARBURETOR The part of the engine, which controls the speed or throttle setting and lean/rich mixture via setting of the needle valve.
CARD II CNS Applications Research
CARPET Airborne jammer of German ground radar 300-600 Megacycle band. Later American developments allowed a more precise use.
CAS Calibrated airspeed
CASA Calibrated Air Speed
CASTER To swivel or rotate slightly.
CAT Commercial Air Traffic
CAT I Instrument Landing Category I (similar: CAT II, CAT III)
CATEGORY 1) As used with respect to the certification, ratings, privileges, and limitations of airmen, means a broad classification of aircraft. Examples inclu...
CATEGORY A with respect to transport category rotorcraft, means multiengine rotorcraft designed with engine and system isolation features specified in Part 29 an...
CATEGORY B with respect to transport category rotorcraft, means single- engine or multiengine rotorcraft which do not fully meet all Category A standards. Catego...
CATEGORY I (CAT I) An ILS facility providing operation down to a 200 foot decision height and an RVR of not less than 2,400 feet.
CATEGORY II (CAT II) An ILS facility providing operation down to a 100-foot decision height and an RVR of not less than 1,200 feet.
CATEGORY II OPERATIONS with respect to the operation of aircraft, means a straight-in ILS approach to the runway of an airport under a Category II ILS instrument approach pr...
CATEGORY III OPERATIONS with respect to the operation of aircraft, means an ILS approach to, and landing on, the runway of an airport using a Category III ILS instrument appr...
CATEGORY IIIA (CAT IIIA) An ILS facility providing operation with no decision height to and along the surface of the runway with external visual reference during the final pha...
CATEGORY IIIB (CAT IIIB) An ILS facility providing operation with no decision height limit to and along the surface of the runway without reliance on external visual reference...
CATEGORY IIIC (CAT IIIC) An ILS facility providing operation with no decision height limit to and along the surface of the runway and taxiways without reliance on external vis...
CAUTION A signal which alerts the operator to an impending dangerous condition requiring attention, but not necessarily immediate action (from MIL-STD-1472D);...
CAVOK Ceiling and Visibility ok (good VFR weather)
CAVU Ceiling And Visibility Unlimited. Perfect flying weather -- no major clouds, no major haze.
CB Cumulonimbus
CBA Cost-Benefit Analysis
CCLIM Course cut limit
CDA Continuous Descent Approach
CDI Course Deviation Indicator
CDM Collaborative Decision-Making
CDR Conditional Route (FUA)
CDTI Cockpit Display of Traffic Information
CDU Control-display unit.
CEAC Confİrence Europİenne de l`Aviation Civile (see ECAC)
CEILING The heights above the earth`s surface of the lowest layer of clouds or obscuring phenomena that is reported as "broken," "overcast," or "obscuration,"...
CENTER An Air Route Traffic Control Center (ARTCC). See Air Route Traffic Control Center.
CENTER LINE Standard aviation term
CENTER OF PRESSURE An imaginary point on the chord of an airfoil where the total of all aerodynamic forces are assumed to act.
CENTER-POD CONFIGURATION A type of airplane whose fairly short fuselage is not connected to the tail surfaces.
CENTRIFUGAL FORCE The force created by a body`s tendency to follow a straight path working against a force which causes it to move in a curve, the resultant force which...
CEP Circular error probability
CERTIFICATED AIRPORT An airport operating under FAR Part 139. The FAA issues airport operating certificates to all airports serving scheduled or unscheduled air carrier ai...
CESC Cescom Maintenance Program.
CFI Certified Flight Instructor.
CFII Certified Flight Instructor IFR (USA)
CFIT Controlled Flight Into Terrain
CFMU Central Flow Management Unit of Euro control
CG Center of Gravity. For air crafting purposes, this is usually considered -- the point at which the airplane balances fore to aft. This point is critic...
CH Center of Gravity
CHAIN HOME An early form of radar using linked radar stations on the east and south coasts of Britain to warn of approaching aircraft.
CHANDELLE A very steep climbing turn where the airplane makes a 180ĝ change of direction.
CHANNEL The frequency number used by the transmitter to send signals to the receiver. If radios transmit on the same frequency, or channel, glitching will occ...
CHARGE JACK The plug receptacle of the switch harness into which the charger is plugged to charge the airborne battery. An expanded scale voltmeter (ESV) can also...
CHARGER Device used to recharge batteries and usually supplied with the radio if NiCad batteries are included.
CHASTISE Codename for the Dambusters` raid. 16-17 May 1943
CHF Swiss Francs (Bankers` code)
CHICKEN STICK A hand-held stick used to flip start a aircraft airplane engine.
CHORD The "depth" of the wing, its distance from leading edge to trailing edge. One of the components used to determine wing area. May vary from root to tip...
CHORD LINE A line drawn from the leading edge of the wing to the trailing edge.
CIA CFMU Internet Application
CILO Capacity Increase Lower airspace
CIRCULAR ERROR PROBABILITY (CEP) A probability that a percentage of two-dimension measurements will lie within a circle of given radius, with the circle centered at truth or mean of t...
CIRCUS A fighter sweep over enemy territory, particularly airfields to draw the fighters into battle.
CIV Civil
CIVIL AIRCRAFT means aircraft other than public aircraft. "Class": (1) As used with respect to the certification, ratings, privileges, and limitations of airmen, mea...
CLARKE 1866 A standard model for computing earth data
CLARKE 1880 A standard model for computing earth data
CLASS A ROTORCRAFT-LOAD COMBINATION one in which the external load cannot move freely, cannot be jettisoned, and does not extend below the landing gear
CLASS B ROTORCRAFT-LOAD COMBINATION one in which the external load is jettison able and is lifted free of land or water during the rotorcraft operation
CLASS C ROTORCRAFT-LOAD COMBINATION one in which the external load is jettisonable and remains in contact with land or water during the rotorcraft operation
CLASS D ROTORCRAFT-LOAD COMBINATION one in which the external- load is other than a Class A, B, or C and has been specifically approved by the Administrator for that operation
CLASS G AIRSPACE (UNCONTROLLEDAIRSPACE) The airspace not designated as Class A, B, C, D or E.
CLEARWAY (1) For turbine engine powered airplanes certificated after August 29, 1959, an area beyond the runway, not less than 500 feet wide, centrally located...
CLIMBOUT SPEED with respect to rotorcraft, means a referenced airspeed which results in a flight path clear of the height-velocity envelope during initial climb out
CLR Clearance (or cleared)
CLSD Closed
CLUNK Term used to describe the weighted end of the fuel pickup line in the fuel tank. The purpose of this is to ensure that the fuel pickup is always in th...
CLUTCH The section of the drive train used to engage the gear when throttle is increased, and disengage while engine is at idle. This ensures that the rotor ...
CMIC Civil Military Interface standing Committee
CMOS Complementary metal oxide semiconductor.
CMU Communications management unit.
CNS Communications, navigation and surveillance.
CNS/ATM Communication Navigation Surveillance/Air Traffic Management
COA Certificate of Airworthiness
COAL SCUTTLE A modification to an aircraft`s existing H2S navigational radar to give a visual bearing every 30 seconds on a signal under investigation.
COCKPIT VOICE RECORDER (CVR) Device that records crew conversations. Used in accident investigations.
CODA Central Office for Delay Analysis (Euro control)
COFA Certificate of Airworthiness
COHERENT DETECTION A technique used in certain ADF receivers to improve useful range.
COLLECTIVE A flight control operated by moving up or down with hand in rotary-wing aircraft, primarily to control lift (altitude); controls collective (total) pi...
COLLECTIVE CUE A vertical flight director cue for rotary-wing aircraft, primarily to control altitude, by changing power; Compare: yoke cue; Symbols: Gamma sub "VERT...
COLLINS Avionics mfgr.
COM Communications
COMBINED CENTER/RAPCON (CERAP) An air traffic facility which combines the functions of an ARTCC and a radar approach control facility.
COMMANDED Controls given to a device, not that the device necessarily obeyed the controls
COMMERCIAL OPERATOR means a person who, for compensation or hire, engages in the carriage by aircraft in air commerce of persons or property, other than as an air carrier...
COMMON TRAFFIC ADVISORY FREQUENCY(CTAF) A frequency designed for the purpose of carrying out airport advisory practices while operating to or from an airport without an operating control tow...
COMMUNICATIONS How well equipment is communicating; Values: operational, degraded, failed
COMMUTER An air carrier operator operating under 14 CFR 135 that carries passengers on at least five round trips per week on at least one route between two or ...
COMPLIMETARY FILTEROMPLEMENTARYFILTER A filter in which the complement of the filter is desired, giving the effect of a high-pass filter by implementing a low-pass filter; a filter for com...
COMPOSITE VIDEO Analog VOR receiver output before processing.
COMPUTER CYCLE In a periodic, cyclical computer system, the most basic, fastest timing loop
CONSOL a kind of low or medium frequency long range navigational aid
CONT Teledyne-Continental (engine mfgr.)
CONTACT DIGITIZER A mechanical device that converts analog information to digital codes by means of electrical contacts.
CONTINUOUS EQUATION A mathematical relationship to describe a function of time, expressed in terms of continuous time; Compare: difference equation, differential equation...
CONTINUOUS TIME Time which can have any point expressed as a real quantity, without regard for any specific interval or processing rate; Compare: discrete time;
CONTINUOUS TIME (CW) A radio carrier broadcast that does not have modulation
CONTOL LAW The mathematical definition of a system used to control or to change the dynamic response of a system;
CONTRAIL Streaks of condensed water vapor created in the air by aircraft flying at high altitudes.
CONTROL INPUTS The controlling influences a pilot exerts on an aircraft`s control surfaces.
CONTROL SURFACE Any one of the various moveable portions of the wings, tail surfaces, or canard.
CONTROL SURFACES The moving, pilot-controllable parts of the air-frame, including flaps, ailerons, rudders and elevators
CONTROLLED AIRSPACE An airspace of defined dimensions within which air traffic control service is provided to IFR flights and to VFR flights in accordance with the airspa...
CONTROLLED SPEED (CTS) A guidance control law parameter, generated by the longitudinal guidance modes; speed that is being controlled Typical Units: ft/s, kt; Dimensions: Le...
CONTROLLER ALTITUDE (CTALT) A guidance control law parameter, generated by the vertical guidance modes; altitude that is being controlled Typical Units: ft; Dimensions: Length;
CONVENTIONAL GEAR The landing gear arrangement where the airplane has a main gear and a tail wheel.
COORDINATED TURN A combination of control inputs that cause a maximally efficient turn.
COPI Communications
CORIOLIS ACCELERATION Tangential acceleration caused by motion on a radial on a rotating surface, in aviation, it is acceleration in the earth`s longitudinal direction caus...
CORKSCREWING Evasive maneuver adopted by British bombers.
CORONA British ground transmitter operating at 2.56 MHz based at Rugby and Leafield. Used to transmit confusing signals over the German night fighter RT cont...
CORRECTED ALTITUDE Measured pressure altitude corrected for instrumentation errors
COUPLED Describes operation of flight director in which automatic flight control system causes flight controls to follow commands from flight director or erro...
COURSE Towards a point at a specified course; Compare: direct
COURSE CUT LIMIT (CCLIM). A guidance control law parameter, generated by the lateral guidance modes; limits the intercept angle of the flight path with a desired course, typica...
COWL The large molded fairing around an engine. It serves two purposes when done right: It helps the airflow go smoothly around the front of the airplane, ...
COWLING A removable metal covering placed over and around an airplane`s engine (s)).
CPDLC Controller-Pilot Data Link Capability (or Communications)
CPL Commercial Pilots License
CR Class Rating
CRAM Conditional Route Availability Message
CRCO Central Route Charge Office of Euro control
CRE Class Rating Examiner
CREEP BACK The progressive dropping of bombs before the target was reached.
CREEPING LINE SEARCH A pattern of equally spaced parallel lines followed for searching the ground from an aircraft; Compare: expanding square search, sector search;
CREWMEMBER means a person assigned to perform duty in an aircraft during flight time
CRI Class Rating Instructor
CRITICAL ALTITUDE means the maximum altitude at which, in standard atmosphere, it is possible to maintain, at a specified rotational speed, a specified power or a speci...
CRITICAL ENGINE means the engine whose failure would most adversely affect the performance or handling qualities of an aircraft
CRM Cockpit Resource Management
CROSS TRACK Perpendicular to the course;
CROSS-OVER EXHAUST A mechanism through which the exhaust from one side of an inline engine is carried to the other.
CROSSTRACK DEVIATION (XTKD) A guidance control law parameter, generated by the lateral guidance modes; distance from the aircraft to a desired course measured along a perpendicul...
CROSSTRACK DEVIATION GAIN (KXTKD) A guidance control law parameter, generated by the lateral guidance modes; relative weighting of cross track deviation in the lateral control law Typi...
CROSSTRACK DEVIATION RATE (XTKR) A guidance control law parameter, generated by the lateral guidance modes; rate of change of cross track deviation Typical Units: ft/s; Dimensions: Le...
CROSSTRACK DEVIATION RATE GAIN(KXTKR) A guidance control law parameter, generated by the lateral guidance modes; relative weighting of the cross track deviation rate in the lateral control...
CRS Conditional Route System (FUA: "Temporary Airways" on request)
CRT Cathode ray tube.
CSDB Commercial standard data bus.
CTAF Common Traffic Advisory Frequency
CTALT Controlled altitude
CTR Control Zone
CTS Controlled speed
CU Cumulus
CUE A indicator to an operator for control placement, tells the operator where to place controls; Synonyms: command
CURSOR See: moving cursor, target cursor
CUST Customs
CUTOFF FREQUENCY The frequency at which the gain of a filter is at an edge of a band, usually taken to be when gain is 0.5, or -3.01dB; the frequency at which the outp...
CVFR Controlled VFR (still existing in some countries)
CVR Cockpit Voice Recorder
CYCLES Pertaining to turbine engines. Cycle begins with starting, continues through full-power, and ends with shutdown.
CYCLIC See: longitudinal cyclic, lateral cyclic;
D Airspace ICAO Class D
D.R. DEAD RECKONING; system of navigation.
DA Drift angle
DADC Digital air-data computer
DAMPED FREQUENCY The frequency of oscillation of an under damped second-order filter; See Also: second-order filter; Symbols: omega; Typical Units: rad/s, Hz; Dimensio...
DAMPING RATIO Control parameter for a second order filter. Symbols: zeta;
DAP Decision Altitude
DARTBOARD Ground-based interference from "ASPIDISTRA" of enemy RT and WT channels in the 300 kHz band.
DATA SOURCE OBJECT (DSO) Software that receives data from a physical device, translates the data into standard units, maintains equipment status, and provides a common interfa...
DATA TRANSFER SYSTEM Total pressure
DATA TRANSFER SYSTEM (DTS). A device for transferring data with avionics, similar to a diskette drive;
DB Decibel
DC Dual Control
DCA Directorate of Civil Aviation
DCT direct
DEAD RECKONING (DR) A method of navigation based on basic information (barometric altitude, magnetic heading, airspeed, wind conditions) from best available source; somet...
DEAD STICK A term used to describe unpowered flight (glide) when the engine quits running.
DECISION HEIGHT with respect to the operation of aircraft, means the height at which a decision must be made, during an ILS or PAR instrument approach, to either cont...
DECISION HEIGHT (DH) With respect to the operation of aircraft, means the height at which a decision must be made during an ILS, MLS, or PAR instrument approach to either ...
DECKER Phosphorous coated rags transported in water and designed to fire crops and forests. This tactic was of little effect.
DEG Degrees
DEL Delay/delayed
DELAY Delays are incurred when any action is taken by a controller that prevents an aircraft from proceeding normally to its destination for an interval of ...
DELTA Difference; error.
DEP Departure
DEPART FROM HOVER (DHOV) A guidance mode providing lateral guidance, longitudinal guidance and vertical guidance for a set heading or bank angle, a set speed, and a set climb ...
DEPARTURES The number of aircraft take-offs actually performed in domestic and international scheduled and non-scheduled passenger/cargo and all-cargo revenue se...
DERIVATIVE Rate of change, usually with respect to time; Symbols: x dot, x prime, x sup (1), dx/dt, Dx;
DERIVED Calculated values for which no direct measurement exists; Compare: estimated, filtered, measured, raw, selected, smoothed
DESALT Desired altitude
DESIRED What must be achieved in order to match a plan; Synonyms: reference;
DESIRED ALTITUDE (DESALT) A guidance control law parameter, generated by the vertical guidance modes; altitude which controlled altitude is attempting to achieve Typical Units:...
DESIRED PATH A trajectory in space determined by guidance to meet the current mission objectives;
DESIRED SPEED (DESS) A guidance control law parameter, generated by the longitudinal guidance modes; speed which controlled speed is attempting to achieve Typical Units: f...
DESS Desired speed
DEV Deviation
DEVIATION Difference from desired;
DEVICE A piece of equipment, a subsystem; Synonyms: physical device, unit
DF Direction Finder
DFAD Digitized Feature Analysis Data
DFS Deutsche Flugsicherung AG
DG Directional gyro
DGNSS Differential GNSS
DGPS Differential global positioning system. LA- prefix refers to local area DGPS; WA- prefix refers to wide-area DGPS signal retransmission schemes.
DGT REN Differential GPS
DH Decision Height
DHOV Depart from hover
DIALED IN Slang term for the condition in which the aircraft is set up to fly smoothly and predictably. This is the state where the mechanics and electronics wo...
DIFFERENCE EQUATION Distance Measuring Equipment
DIFFERENT EQUATION A mathematical relationship to model a continuous function, expressed in terms of derivatives; Initial conditions are usually given or implied. In avi...
DIGITAL MAP GENERATOR (DMG) Digital equipment that produces map video, and sometimes contains TRN; uses Digital Terrain Elevation Data and Digitized Feature Analysis Data; Displa...
DIGITAL TERRAIN ELAVATION DATA(DTED) On a digital map, data for elevation of terrain; DTED is usually provided by Defense Mapping Agency; Compare: Digitized Feature Analysis Data;
DIGITIZED FEATURE ANALYSIS (DFAD) On a digital map, data for cultural features such as buildings and roads; DFAD is usually provided by Defense Mapping Agency; Compare: Digital Terrain...
DIGITZER Any electronic device capable of converting information to a digital format; usually refers to encoding devices that convert sensed altitude into a tr...
DIHEDRAL The V-shaped bend in the wing. The upward angle of the airplane`s wings with respect to the horizontal. Typically, more dihedral causes more aerodynam...
DIMENSIONLESS No units, such as ratios; Synonyms: unit less;
DINA An American improvement of MANDREL airborne jamming device operating in the 95-210 MHz band. Also named PIPERACK when used to counter FuG 220 AI radar...
DING Minor dent or damage to the structure. Also, a nick in a prop. Dinged props must be replaced.
DIRECT Towards a point along the shortest distance; Compare: course
DIRECTION bearing.
DIRECTIONAL STABILITY The tendency of an aircraft to keep flying the direction its pointed.
DIRTY Extension of gear, hook, flaps, etc. for slow speed flight or landing.
DIRTY UP Extension of gear, hook, flaps, etc. for slow speed flight or landing.
DISCRETE TIME Time divided into quantized intervals; in avionics, time is usually divided into equal intervals to create a periodic process; Compare: continuous tim...
DISCRETE-TIME EQUATION A mathematical relationship to describe a function of time, expressed in terms of discrete time; Compare: continuous-time equation, difference equatio...
DISTANCE Method of measurement dependent on use; Synonyms: range;
DISTANCE MEASUREING EQUIPMENT(DME) Equipment for measuring distance, usually from an aircraft to a ground station; usually part of a Tactical Air Navigation system
DISTRESS A condition of being threatened by serious and/or imminent danger and of requiring immediate assistance.
DITCH To land safely somewhere other than a runway.
DIVERT To change from a scheduled landing base to an alternate airfield.
DLA Delay (Message of an ICAO FPL)
DME Distance Measuring Equipment.
DMG Digital Map Generator
DNS Doppler Navigation System
DOF Distance Measuring Equipment
DOMESTIC OPERATIONS Operations within and between: the 50 states of the United States, the District of Columbia, the Commonwealth of Puerto Rico, and the United States Vi...
DOP Dilution of Precision (GPS)
DOPPLER A technique for measuring velocity by radiating and determining frequency shift
DOPPLER NAVIGATION SYSTEM (DNS,DPLR) A navigation for measuring velocity by radiating and determining frequency shift;
DORSAL FIN An extension of the vertical fin forward of the main part of the fin, and against the fuselage. On the top, or "dorsal" side of the aircraft.
DOWN THRUST Downward angle of the engine relative to the centerline of the airplane. Down thrust helps overcome the normal climbing tendency caused by the torque ...
DP Deal Pending
DPLR Doppler navigation system
DR Ded (deduced) reckoning.
DRAG Force created by an airfoil moving through atmosphere, opposite to the direction of motion. The air resistance to forward motion. Drag can be increase...
DRIFT Slow, monotonic change in measured data
DRMS Distance root mean squared.
DRUMSTICK Ground based interference with enemy WT transmissions in the 3-6 MHz bands
DSO Data source object
DSP Data Processing
DTED Digital Terrain Elevation Data
DTK Desired track
DTU Data transfer unit
DUAL RATES Radio function used to adjust control sensitivity.
DUAT Direct User Access Terminal (US Computer Self-Briefing system)
DUNKEL-NACHTJAGD - DARK NIGHT HUNT; German night fighter zone not backed by searchlights
DUPLES Separate channels for transmitting and receiving
DœPPEL The German version of WINDOW. Strips of silver paper dropped to confuse the ground radars
E Airspace ICAO Class E
EAA Experimental Aircraft Association
EAD European AIS Database
EAG European ATFM Advisory Group
EANPG European Air Navigation Planning Group (ICAO)
EARLY EXTENDED VALIDATION INTEGRATIONPROGRAM (EEVIP) An FAA program, first implemented for the Boeing 777, to give "out-of-the-box" ETOPS clearance to a new plane, rather than waiting for a couple of yea...
EAROM Electrically alterable read-only memory, a type of digital memory device.
EART-REFERENCED FLIGHT PATHANGLE Angle in vertical plane of airspeed vector and groundspeed vector; usual definition for flight path angle; Compare: air-mass flight path angle; Symbol...
EARTH COORDINATES Coordinates referenced to the earth; See Also: east-north-up; Compare: body coordinates, stability coordinates
EARTH DATA Environmental data related to the earth at some point of interest; usually a function of latitude and longitude
EARTH ECCENTRICITY A measure of the degree to which the earth is oblate; Symbols: epsilon;
EARTH MODEL The earth model computes data related to the earth. Most data is a function of position. Standard models are: International, Clarke 1866, Clarke 1880,...
EARTH RADIUS Radius of the earth, function of position, separate radii for longitudinal radius and for lateral radius; See Also: state data; Symbols: rho; Typical ...
EARTH RADIUS BEST SPHERE Gaussian radius of curvature
EARTH RADIUS EAST/WEST Prime radius of curvature
EARTH RADIUS NORTH/SOUTH Meridian radius of curvature
EARTH SPEED Total velocity measured with respect to a plane tangent to the earth`s surface at the current position; a vector composed of velocity north, velocity ...
EAS European Air Sports
EASA European Aviation Safety Authority (planned to replace JAA)
EAST-NORTH-UP (ENU) A standard earth coordinate frame and sign convention, where east, north, and up are positive; vertical, or V, is sometimes used in place of up; Synon...
EAST-NORTH-VERTICAL (ENV) East-north-up.
EATCHIP European Air Traffic Control Harmonization Implementation Project
EATMP European Air Traffic Management Plan
EATMS European Air Traffic Management System
EATS Empire Air Training Scheme
EBAA European Business Aviation Association
EC European Commission
ECAC European Civil Aviation Conference ("Association" of Europe`s CAAs)
ECI Earth Centered Inertial
ECM Electronic Counter-Measures.
ECOGAS European Council of General Aviation Support
EDF Electric ducted fan. A battery-powered fan (rather than exterior propeller) driven aircraft.
EEC Euro control Experimental Centre
EEPROM Electrically Erasable Programmable Read-Only-Memory
EET Estimated Elapsed Time
EFATO Engine Failure At Take-Off (JAR-FCL)
EFDP European Flight Data Processing
EFIS Electronic Flight Instrument System
EFTS Elementary Flying Training School
EGNOS European Geostationary Navigation Overlay System
EGT Exhaust gas temperature indicator.
EHS Enhanced Surveillance (Mode S, 2nd step)
EHSI Electronic Horizontal Situation Indicator
EICAS Engine indicating and crew alerting system.
ELBA Emergency Locator Beacon-Aircraft
ELECTRIC STARTER A hand-held electric motor used for starting a aircraft airplane engine. Usually powered by a 12-volt battery.
ELEV Elevation
ELEVATION An angle in the vertical plane through a longitudinal axis; height above mean sea level, usually of terrain;
ELEVATOR Pitch control. Causes the aircraft to raise or lower its nose, resulting in a climbing or diving response. Moving the elevator down causes the tail to...
ELT Emergency Locator Transmitter (crash-activated transmitter)
EMC EATMP Management Committee
EMIL ; Nickname for the Bf109E
EMPENNAGE The vertical and horizontal tail surfaces of an airplane.
EN ROUTE AIR TRAFFIC CONTROLSERVICES Air traffic control services provided aircraft on IFR flight plans, generally by centers, when these aircraft are operating between departure and dest...
ENCAL Encoding Altimeter
ENCODER Displays aircraft`s altitude on ground-based radar screens.
ENGINE The methanol or gasoline fueled power plant used in a aircraft. Two or four-stroke gasoline and glow engines are very popular in aircraft. Four-stroke...
ENGINE COWL A removable covering placed over and around an airplane`s engine.
ENPLANEMENT A revenue passenger boarding an aircraft.
ENPRM Euro control (European?) Notice of Proposed Rule Making
ENU East-north-up
ENV East-north-vertical
ENVIRONMENTAL DATA Atmospheric data and earth data
EOBT Estimated off-block time
EP European Parliament
EPOXY A two-part resin/hardener glue that is extremely strong. It is generally available in 6 and 30-minute formulas. Used for critical points in the aircra...
EQUIPMENT STATUS Operational status of a piece of equipment consisting of a status indicator and status words; Synonyms: health;
ERA European Regional Airlines Association
EROS Brand Name for Oxygen Mask
ERPROBUNGS GRUPPE Luftwaffe formation for the evaluation of new tactics or techniques
ERROR Difference between desired and measured data; Synonyms: delta;
ESA European Space Agency
ESC Economic Social Committee
ESTIMATED Data that is the result of filtering two or more signals; Compare: derived, filtered, measured, raw, selected, smoothed
ETA Estimated Time of Arrival. The time the flight is estimated to arrive at its destination.
ETD Estimated Time of Arrival
ETFMS Enhanced Tactical Flow Management System
ETOPS Extended Twin-engine operations. FAA designation of over-ocean flights far from possible emergency landing strips, in which the possibility of engine ...
ETSI European Telecommunication Standardization Institute
EU European Union
EUAPA European Union Airplane Pilots Association
EULER ANGLES Pitch, roll, and yaw
EULER PARAMETERS Four parameters for specifying quaternion; Symbols: e sub
EUR European Region
EUROCAE European Organization for Civil Aviation Equipment
EVEREST A standard model for computing earth data
EXPANDED SCALE VOLTMETER (ESV) Device used to read the battery voltage of the on- board battery pack or transmitter battery pack.
EXPANDIG SQUARE SEARCH A pattern of progressively larger squares (a "square spiral") followed for searching the ground from an aircraft; Compare: creeping line search, secto...
EXPEDITE Used when prompt compliance is required to avoid the development of an imminent situation.
EXPONENTIAL This radio function allows the air crafter to adjust the sensitivity of the control towards the center. This will make the small stick motions very pr...
EXTENDED OVER-WATER OPERATION 1) With respect to aircraft other than helicopters, an operation over water at a horizontal distance of more than 50 nautical miles from the nearest s...
EXTERNAL-LOAD ATTACHING means the structural components used to attach an external load to an aircraft, including external-load containers, the backup structure at the attach...
EXTROPOLATE Function to determine values from two or values in a table, when the given value lies outside of the range of the table; usually linear but can be hig...
F Airspace ICAO Class F
FA Area Forecast (Meteo)
FAA Federal Aviation Administration.
FADEC Full authority digital engine control.
FAF Federal Aviation Administration
FAILSAFE A PCM function which moves servos to a pre programmed position if transmitter signal is lost or corrupted.
FAIRING A shaped area used to smooth out, streamline, or "fair", the joint between two members of an airplane to reduce drag. A wing fairing joins the wing an...
FANS Future Air Navigation System (an ICAO project group)
FAR Federal Aviation Regulations. The laws under which airmen in the US fly.
FAR 36 NOISE LEVELS In order to meet FAR 36 Stage 3 requirements, the maximum noise level permitted is: *Take Off 89.0 EPNdB *Sideline 94.0 *Approach 98.0
FAWP Final Approach Waypoint
FBO Fixed Base Operator
FBO (FIXED BASE OPERATOR) The small but important building near the ramp and runways of a small airport, from which airfield activity is coordinated.
FCC Federal Communications Commission (USA)
FCL Flight Crew Licensing
FCM Flight Confirmation Message
FCS Flight control system
FD Winds and Temperature aloft Forecast
FDE Fault detection and exclusion (GPS)
FDP Flight Data Processing
FDR Flight Data Recorder
FDS Flight Director System
FE Flight Examiner
FEDERAL AVIATION REGULATION(FAR) 14 CFR FAR Part 91 - General Aviation (portions apply to all operators) 14 CFR FAR Part 103 - Ultra light Vehicles 14 CFR FAR Part 105 - Parachute Jum...
FERRY FLIGHT A flight for the purpose of: 1. Returning an aircraft to base. 2. Delivering an aircraft from one location to another. 3. Moving an aircraft to and fr...
FFAS Free Flight Air Space (Euro control Definition)
FFON Flight Phone
FI Flight Identity (Code) - (Mode S Transponder)
FIC Flight Information Center
FIDGET Interference of enemy high frequency night-fighter transmissions.
FIE Flight Instructor Examiner
FIELD CHARGER A fast battery charger designed to work from a 12-volt power source, such as a car battery.
FIGURE 9 Can be an "official" competition maneuver, or a badly-done loop. When the aircraft flies over the top of a loop and picks up too much speed, the momen...
FILTER A device to alter a signal; software to alter a data steam; See Also: averaging filter, band-pass filter, complementary filter, first-order filter, hi...
FILTERED Data that is the result of filtering a signal; filtering is usually more sophisticated than smoothing Compare: derived, estimated, measured, raw, sele...
FIN, VERTICAL FIN The fixed portion of the vertical tail surface.
FINAL Used to mean an aircraft is on proper heading, descent rate, airspeed, and altitude during runway approach prior to landing, or to a target prior to w...
FIO Flight Information Office
FIR Flight Information Region
FIRE RESISTANT (1) With respect to sheet or structural members means the capacity to withstand the heat associated with fire at least as well as aluminum alloy in di...
FIREPROOF (1) With respect to materials and parts used to confine fire in a designated fire zone, means the capacity to withstand at least as well as steel in d...
FIRST-ORDER FILTER-ORDER FILTER A filter in which the output follows the input, only more slowly; It is usually implemented in software as a difference equation of period T. The firs...
FIS Flight Information Service
FIS-B Flight Information Service-Broadcast
FISHPOND Device fitted to H2S to enable wireless operators to scan beneath the bombers for night fighter attacks from below.
FIX A determination of one`s position based on external data, such as a known terrain point
FIXED WING An airplane, as opposed to a rotary wing / helicopter;
FL Flight Level, Altitude x100 = feet AMSL (FL 70 = 7000ft) at ISA
FLAK Flieger Abwehr Kanonen. German anti-aircraft guns
FLAME RESISTANT means not susceptible to combustion to the point of propagating a flame, beyond safe limits, after the ignition source is removed
FLAMMABLE with respect to a fluid or gas, means susceptible to igniting readily or to exploding
FLAP EXTENDED SPEED means the highest speed permissible with wing flaps in a prescribed extended position
FLAPS Hinged control surface located at the trailing edge of the wing inboard of the ailerons that act together to increase the lift characteristics of the ...
FLARE The point during the landing approach in which the pilot gives an increased amount of up elevator to smooth the touchdown of the airplane. This maneuv...
FLASH RESISTANT means not susceptible to burning violently when ignited
FLENSBURG ; (FuG 227) German air interception homing device.
FLGHT PATH ANGLE (FPA) Angle in vertical plane of earth speed vector and groundspeed vector (usual definition), earth-referenced flight path angle; angle in vertical plane o...
FLIGHT BOX A special box used to hold and transport all equipment used at the flying field.
FLIGHT CONTOLS Controls in a cockpit for flying an aircraft; primary flight controls are wheel, yoke, cyclic, pedals, throttle, and collective; secondary flight cont...
FLIGHT CONTROL SYSTEM (FCS) A primary flight control system or an automatic flight control system;
FLIGHT DATA RECORDER (FDR) An electronic device that records aircraft maneuvers. Used in accident investigations.
FLIGHT DIRECTOR System, usually software, that generates stick position cues from state errors - typically three cues:. pitch, roll, and throttle for fixed-wing and l...
FLIGHT LEVEL (FL) A level of constant atmospheric pressure related to a reference datum of 29.92 inches of mercury. Each is stated in three digits that represent hundre...
FLIGHT PACK OR AIRBORNE PACK All of the radio equipment installed in the airplane, i.e., Receiver, Servos, Battery, Switch harness.
FLIGHT PHONE Air-to-ground telephone system.
FLIGHT PLAN Specified information relating to the intended flight of an aircraft that is filed orally or in writing with an FSS or an ATC facility.
FLIGHT SERVICE STATION (FSS) Air traffic facilities which provide pilot briefing, enroute communications and VFR search and rescue services, assist lost aircraft and aircraft in e...
FLIGHT VISIBILITY means the average forward horizontal distance, from the cockpit of an aircraft in flight, at which prominent unlighted objects may be seen and identif...
FLIGHTCREW MEMBER means a pilot, flight engineer, or flight navigator assigned to duty in an aircraft during flight time. "Flight level" means a level of constant atmos...
FLIGHTLINE Where aircraft are parked between missions.
FLIR Forward-Looking Infrared
FLOATS Long, canoe-shaped structures that allow an airplane to land on water. They are not a part of the aircraft structure, but suspended below the fuselage...
FLOS Forward Looking Infra-Red
FLOWER an intruder sortie, usually by Mosquitoes, against German night-fighter airfields during bomber operations.
FLT Flight
FLUTTER A phenomenon whereby the elevator or aileron control surface begins to oscillate violently in flight. This can sometimes cause the surface to break aw...
FLUX VALVE A device to measure the earth`s magnetic flux; a compass
FLY OVER A position update by flying directly over a known point
FLYING BOAT The type of aircraft where the fuselage has the lower portion shaped like a power boat. The plane lands on water directly onto the fuselage. There may...
FM Frequency Modulation. This describes the mode of transmission of radio signal from transmitter to receiver.
FMCS Flight management computer system.
FMD Frequency Modulation
FMS Flight Management System
FNPT Flight Management System
FOCA Federal Office for Civil Aviation (Swiss CAA - see BAZL)
FOD Foreign Object Damage
FOG Fiber-optic gyro.
FORE, FORWARD Towards the front. Used such as: "...the forward edge of the rib...", or as in: "...with fore and aft movement...."
FOREIGN AIR CARIER means the carriage by aircraft of persons or property for compensation or hire, or the carriage of mail by aircraft, or the operation or navigation of...
FOREIGN AIR CARRIER means any person other than a citizen of the United States, who undertakes directly, by lease or other arrangement, to engage in air transportation
FOREIGN AIR TRANSPORTAION means the carriage by aircraft of persons or property as a common carrier for compensation or hire, or the carriage of mail by aircraft, in commerce b...
FORWARD ELEVATION A control surface used to tilt an airplane up or down and mounted on the front rather than the rear of an airplane.
FORWARD-LOOKING INFRARED (FLIR) Sensor equipment used to supplement AGR, extend the aircraft visual search capability and provide position information for guidance and navigation upd...
FPA Flight path angle
FPL Flight Plan (for ATC)
FPM Feet Per Minute. Unit of measure, used for ROC or sometimes speed.
FREEDOM OF INFORMATION ACT (FOIA) The Freedom of Information Act (FOIA) allows all U.S. citizens and residents to request any records in possession of the executive branch of the feder...
FREIJAGD The use of Bf109s in independent, (usually high altitude), fighter sweeps over southern Britain to divert Fighter Command`s response.
FREQUENCY CONTROL The FCC has allowed the 72MHz (72.010 - 72.990) band to be used for R/C aircraft operations. This band is divided up into many different channels in w...
FREYA :;; (FuG 221) A series of German early warning long range radars.
FSDM feet per minute (vertical speed)
FSDO Flight Standard District Office (FAA USA)
FSS Flight Service Station
FT feet (approx 0.3 Meters)
FTD Flight Training Device (lower category "simulator")
FTO Flight Training Organization (Flight School)
FUA Flexible Use of Airspace
FUEL The methanol/nitro methane/lubricant mix used to fuel aircraft engines. A helicopter fuel mix has a higher concentration of lubricant to counter the l...
FUG (FUNK GER¤T) a series of airborne homing devices used to illuminate MANDREL, MONICA, H2S and ASV. Later modifications permitted their use as search radars for nigh...
FULL DE-ICE Complete anti - and/or de-ice equipment installed on wings, tail, props, and windshield.
FULL PANEL All gyros necessary for instrument flight.
FUSE Fuselage, main body
FUSELAGE The body of an airplane.
FVS Fliegerische Vor-Schulung
G Acceleration force unit (1G = Earth Gravity
G-H British two-station radio direction finding system used as a bombing aid
G/S Glide slope receiver and indicator.
G/S SEL Groundspeed select
GA Go around
GA General Aviation and Aerial Work (all non-commercial civil aviation)
GAC General Aviation Center
GAFOR General Aviation Forecast (Weather)
GAIN Gyro sensitivity. When too low, the tail will not hold position well. When too high, the surface being dampened by the gyro will tend to wag, or hunt ...
GAL Gallons (usually US 3.78 liter, may be Imperial 4.54 liter)
GALLEY On-board meal service equipment.
GAMA General Aviation Manufacturers Association (USA)
GARDENING RAF codeword for mine laying by aircraft
GAS DISCHARGE A type of luminescent digital display.
GASSER Slang for a aircraft using a gasoline engine as a power plant.
GAT General Air Traffic
GATT General Agreement on Trade and Taxes
GAUSSIAN RADIUS OF CURVATURE Radius of the earth for the best fitting sphere at a given position; Synonyms: earth radius best sphere; Symbols: rho sub G; Typical Units: ft; Dimens...
GBAS Ground Based Augmentation System (DGNSS/DGPS/LAAS)
GCA Ground Controlled Approach ("Talk-down")
GCI Ground Communication Infrastructure
GCLP Guidance control law parameter
GCR Ground clutter rejection.
GEAR Landing gear, the undercarriage and wheels of an aircraft.
GEE RAF navigational aid which could provide the navigator with a fix from pulses transmitted by three ground stations. Range approximately 300 miles.
GEN General
GENDEC General Declaration Customs Form see full size, download zipped form,
GENERAL AVIATION That portion of civil aviation which encompasses all facets of aviation except air carriers holding a certificate of public convenience and necessity ...
GENERAL ELECTRIC (GE) Engine Mfr.
GEO Geostationary Earth Orbit (Satellite)
GEOCENTRIC LATITUDE Latitude measured with respect to horizontal through mass center of the earth; Compare: astronomical latitude, geodetic latitude; Symbols: Phi sub C; ...
GEODETIC LATITUDE Latitude measured with respect to normal to reference ellipsoid; Compare: astronomical latitude, geocentric latitude; Symbols: Phi sub T; Typical Unit...
GESCHWADER Luftwaffe formation approximately equivalent to a Wing, comprising 90-120 aircraft divided into Gruppen, each of 20-30 aircraft.
GFT General Flight Test (JAR-FCL)
GHZ Gigahertz (1`000 MHz or 1`000`000`000 Hertz)
GIMBALED INERTIAL SENSOR Accelerometers mounted to a platform which is free to rotate, with gyroscopes to measure rotation and servomotors to maintain a fixed attitude with re...
GISELA German intruder operation when the night fighters followed the British bombers back to their bases
GLD Glider
GLIDESCOPE Angle approach a runway; Symbols: Gamma; Typical Units: rad, deg;
GLITCH Momentary radio problem that never happens unless you are over trees or a swamp.
GLOBAL POSITIONING SYSTEM (GPS) A navigation sensor based on satellites; A Global Positioning System (GPS) provides highly accurate navigation data: position, velocity, and time refe...
GLONASS Global Orbiting Navigation Satellite System (Russian GNSS)
GLOW FUEL A Methanol based fuel, with a lubricating agent, used in most aircraft engines. Most aircraft fuels also use a percentage of nitro methane.
GLOW HEATER This is the plug that is used to help ignite the fuel in a aircraft engine. The combustion of the fuel in the engine keeps the element hot between cyc...
GLS GPS Landing System
GLU GNSS landing unit. Provides precision GPS guidance to the runway in Category III operations.
GM-P10 GM=Morocco, P10=Prohibited Area No. 10.
GND Ground
GNSS Global navigation satellite system.
GO AROUND (GA) A basic guidance mode, providing lateral guidance, longitudinal guidance and vertical guidance to climb then to accelerate, while maintaining a wings-...
GOLD CROWN Trade name owned by King Radio Corp.
GPA Groupe Parlementaire pour l`Aviation
GPADIRS Global positioning, air data, inertial reference system.
GPH Gallons (US) per hour
GPS Global positioning system
GPS-DNS Global Positioning System
GPS-INS GPS using INS
GPWS Ground Proximity Warning System
GRAS Ground Proximity Warning System
GRAVITATIONAL ACCELERATION Acceleration caused by the force of gravity; Symbols: g; Typical Units: ft/s-squared, g; Dimensions: Length / Time-squared;
GRAVITY Force exerted by gravity; gravity sometimes includes effects of the earth`s rotation; gravity is often treated as a constant, but for greater accuracy...
GRID NORTH Standard aviation term.
GRIVATION Symbols: nu sub g ; Typical Units: rad, deg;
GROSS-BATTERIEN Large batteries of German anti-aircraft guns.
GROUND AIR A/C unit to cool aircraft while on the ground.
GROUND EFFECT The cushion of air that the aircraft rides on when close to the ground. This will decrease the amount of elevator needed to maintain a constant altitu...
GROUND GROCER A jamming device used to interfere with FuG 202 and 212 AI radar
GROUND SPEED The speed of an aircraft relative to the surface of the earth.
GROUND TRACK ANGLE (GTA) Direction of ground speed vector with respect to true north; Synonyms: true track; Symbols: eta; Typical Units: rad, deg;
GROUND VISIBILITY prevailing horizontal visibility near the earth`s surface as reported by the United States National Weather Service or an accredited observer
GROUNDSPEED The speed over the ground; earth speed projected to a horizontal plane; Symbols: V sub g; Typical Units: kt, ft/s; Dimensions: Length / Time;
GROUNDSPEED SELECT (G/S SEL) A basic guidance mode, providing longitudinal guidance to an operator selected groundspeed;
GRUPPE subdivision of a geshwader, each group having 20-30 aircraft assigned
GS Groundspeed.
GSC Ground Speed
GSM General Standard for Mobile Communication (Mobile phones)
GTA Ground track angle
GTWO Gross Take off Weight
GUIDANCE System, usually software, that determines state errors of desired state minus current state, typically three states: heading, altitude, and speed;
GUIDANCE CONTROL PARAMETER (GCLP) One of several parameters for the guidance control laws, generated by individual guidance modes; See Also: altitude error scale factor, altitude integ...
GUSTAV Nickname for the Bf109G
GYRO A mechanical or electronic device which helps to stabilize the orientation of the aircraft by sensing rotation, and moving the appropriate servo to co...
GYRODYNE a rotorcraft whose rotors are normally engine-driven for takeoff, hovering, and landing, and for forward flight through part of its speed range, and w...
GYROPLANE A rotorcraft whose rotors are not engine-driven, except for initial starting, but are made to rotate by action of the air when the rotorcraft is movin...
GYROSCOPE (GYRO) An inertial device for measuring change of attitude (pitch rate, roll rate, and yaw rate); gyroscopes usually consist of a gimbled, rotating mass; gyr...
H Helicopter (JAR-FCL)
H24 Operating 24 hours
H2S ?
HACK An aircraft used for communications or recreational purposes.
HAPPY VALLEY ; RAF nickname for the Ruhr industrial area.
HB- Swiss nationality marks for aircraft registration
HDG Heading
HDG SEL Heading select
HEADER TANK This is a small fuel tank used in line between the main tank and the carburetor. The purpose of the header tank is to ensure that the fuel fed to the ...
HEADING Direction on a compass that aircraft is pointed, measured with respect to true north or magnetic north; Symbols: psi; Typical Units: rad, deg;
HEADING ERROR A basic output from guidance to flight director, indicating the difference between actual heading and desired heading; Symbols: DELTA psi; Typical Uni...
HEADING HOLD This describes a type of Gyro which senses rotation, and maintains direction. This is accomplished by sensing the rate of motion, and the time of moti...
HEADING LOCK Slang term for Heading Hold Gyro.
HEADING SELECT (HDG SEL) A basic guidance mode, providing lateral guidance to an operator selected heading (magnetic heading or true heading, again, operator selectable);
HEALTH Equipment status
HEINRICH German transmitter introduced to jam GEE.
HEL Helicopter
HELICOPTER A rotorcraft that, for its horizontal motion, depends principally on its engine-driven rotors.
HELIPORT an area of land, water, or structure used or intended to be used for the landing and takeoff of helicopters
HELLE NACHTJAGD ILLUMINATED NIGHT HUNT; German night fighter system backed by searchlights
HEO High Earth Orbit
HERTZ (HZ) Cycles per second, used to describe radio frequencies; usually with the prefix k for kilo (one thousand), M for mega (one million) or G for giga (one ...
HF High Frequency radio equipment.
HF COM High Frequency Communication.
HG High Frequency
HIGE Hover In Ground Effect
HIGH-PASS FILTER (HPF) A filter that allows frequencies above a cutoff frequency to pass while attenuating frequencies below the cutoff frequency;
HIMMELBETT FOUR POSTER BED; German radar-backed night fighter system.
HIRF High intensity radiated field.
HIRL High Intensity Runway Lights
HIS Horizontal Situation Indicator
HIT (OR TO BE HIT) Sudden radio interference which causes your aircraft to fly in an erratic manner. Most often caused by someone turning on a radio that is on your freq...
HITS Highway In The Sky (Flight/NAV display concept)
HJ Operating hours during daylight
HMI Human Machine Interface
HOGE Hover Out of Ground Effect
HOL Holidays (MON-TUE-WED-THU-FRI-SAT-SUN-HOL)
HOLD To maintain some aspect (s) of aircraft state, such as heading, airspeed, altitude, pitch
HOOK In the US Navy, a target cursor;
HORIZONTAL STABILIZER (STAB) The horizontal tail surface at the back of the fuselage which provides aerodynamic pitch stability to the airplane.
HOT START An engine which has been running will tend to remain hot for a short time. During this period, it is possible to restart the engine by turning the cra...
HOUGH A standard model for computing earth data
HOURS FLOWN The airborne hours in domestic and international scheduled and non-scheduled revenue service, computed from the moment an aircraft leaves the ground u...
HOVER The art of flying without moving. This can also be an illusion, depending on wind speed. For airplanes, this is a 3D maneuver also known as a "hanger"...
HOVER HOLD (HVR SYM) A basic guidance mode, providing lateral guidance and longitudinal guidance to maintain an operator selected north velocity and east velocity; if the ...
HP Horsepower
HPA High-power amplifier.
HPF High-pass filter
HQ Horsepower
HUD Heads-up display
HVR SYM Hover hold
HX Head-Up Display
HYDRAULIC LOCK Hydraulic lock happens when the engine becomes flooded with fuel, to the point where the piston cannot compress it in the combustion chamber. This can...
HYSTERESIS A function in which the algorithm for computing output changes at defined events or thresholds, such that output follows one path as input increases a...
IACA International Air Charter Association
IAF Initial Approach Fix
IAOPA International Council of Aircraft Owner and Pilot Associations
IAOPA-EUR IAOPA European Region
IAS Indicated airspeed
IAS-TFB Indicated Air Speed
IATA International Air Transport Association
IAWP Initial Approach Waypoint
IBC Ils Back Course
IBIT Initiated built-in-test
IC Interrogator Codes (II and SI codes)
ICAO International Civil Aviation Organization (a UN-Suborganisation)
ICD Interface Control Document
ID Identification
IDL Interface Definition Language
IDLE THRUST the jet thrust obtained with the engine power control level set at the stop for the least thrust position at which it can be placed
IDS Infrared Detecting Set
IFF IDENTIFICATION FRIEND OR FOE. Equipment carried by aircraft of both sides which issued a signal identifying it as friendly.
IFPS Integrated Flight plan Processing System of Euro control
IFPUV IFPS Validation System (offline Route Verification by Internet)
IFR Instrument Flight Rules ("all" weather operations rules) IG (al) Imperial Gallon (4,54 Liter)
IFR AIRCRAFT/IFR FLIGHT An aircraft conducting flight in accordance with instrument flight rules.
IFR CONDITIONS weather conditions below the minimum for flight under visual flight rules
IFR OVER-THE-TOP with respect to the operation of aircraft, means the operation of an aircraft over-the-top on an IFR flight plan when cleared by air traffic control t...
II Interrogator Identity (Code) - (Mode S Transponder)
IINTERSTATE AIR COMMERCE the carriage by aircraft of persons or property for compensation or hire, or the carriage of mail by aircraft, or the operation or navigation of aircr...
ILS Instrument Landing System. A precision instrument approach system, generally used to land at fields experiencing weather.
ILS APPROACH Instrument Landing System
ILS BACK COURSE (IBC) Operation of ILS in which the runway is approached in reverse direction, giving only lateral guidance; Compare: ILS Front Course;
ILS FRONT COURSE Operation of ILS in which the runway is approached in forward direction, giving lateral, longitudinal, and vertical guidance; sometimes called ILS Com...
IM Instrument Landing System
IMC Instrument Meteo Conditions (weather requiring IFR flight)
IMMELMANN A maneuver originally used to reverse direction in combat. The airplane noses up and over onto its back. It then rolls upright and continues in the di...
IN inch
IN-LINE ENGINE An engine in which the cylinders are mounted in a straight line or else in two, connected at an angle.
INCIDENCE The angle of one portion of a aircraft when compared to another portion of the aircraft. For example, if the stabilizer is perfectly parallel to the g...
INCIDENCE METER Used to measure the angle of attack of an airfoil, can be used to measure blade pitch, or paddle pitch.
INCIDENT An occurrence other than an accident associated with the operation of an aircraft, which affects or could affect the safety of operations.
INDICATED AIRSPEED "" means the speed of an aircraft as shown on its pitot static airspeed indicator calibrated to reflect standard atmosphere adiabatic compressible flo...
INDICATED AIRSPEED (IAS) The speed of an aircraft as shown on its pitot static airspeed indicator calibrated to reflect standard atmosphere adiabatic compressible flow at sea ...
INDICATED ALTITUDE The altitude as shown by an altimeter.
INERTIAL Based on inertia, such as with an INS or an AHRS
INERTIAL NAVIGATION SYSTEM (INS) A totally self-contained system which requires no information from outside references. Provides aircraft position and navigation information in respon...
INERTIAL NAVIGATION UNIT (INU) A self-contained Inertial Navigation System;
INFRARED DETECTING SET (IDS) Forward-Looking Infrared;
INHG inches of Mercury (unit of pressure)
INITIALIZATION A basic control to a data source from controls and displays for initializing a device. Initiated by power-on, operator, driver, or MC; During initiali...
INITIATED BUILT-IN-TEST (IBIT) Self tests running internal to a device initiated external to the device, usually an operator, causing the device to temporarily cease normal operatio...
INNER MARKER Innermost marker beacon on an ILS
INS Inertial Navigation System
INSTRUMENT means a device using an internal mechanism to show visually or aurally the attitude, altitude, or operation of an aircraft or aircraft part
INSTRUMENT FLIGHT RULE (IFR) A set of rules governing the conduct of flight under instrument meteorological conditions.
INSTRUMENT LANDING SYSTEM (ILS) Inertial Navigation System
INSTRUMENT METEOROLOGICAL CONDITIONS(IMC) Meteorological conditions expressed in terms of visibility, distance from clouds, and ceiling less than minima specified for visual meteorological con...
INSTRUMENT OPERATIONS Arrivals or departures of an aircraft in accordance with an IFR flight plan or special VFR procedures or an operation where IFR separation between air...
INSTRUMENTATION Hardware to measure and to monitor a system
INT Interior
INTAKE An air inlet on an aircraft. You can have a carburetor intake, cooling intake, air conditioning intake (on full-size aircraft), and so on. Named becau...
INTEGRATE To combine multiple systems; Also, to compute to integral of;
INTEGRATED AVIONICS COMPUTER(IAC) Central processor of a Honeywell integrated cockpit system.
INTEGRATED AVIONICS PROCESSINGSYSTEM (IAPS) Central processor of a colins integrated cockpit system
INTEGRATOR A function that integrates; Many types of integrators exist; in fact, they constitute entire books. Avionics software usually relies on rectangular, s...
INTERNATIONAL A standard model for computing earth data
INTERPOLATE Function to determine intermediate values from two or values in a table; usually linear but can be higher order; endpoints are either extrapolated or ...
INTERROGATION A request of data
INTERSTATE AIR TRANSPORTATION means the carriage by aircraft of persons or property as a common carrier for compensation or hire, or the carriage of mail by aircraft in commerce: (...
INTLIM Path integral limit
INTMAGLIM Altitude integral limit
INTRASTATE AIR TRANSPORTATION means the carriage of persons or property as a common carrier for compensation or hire, by turbojet-powered aircraft capable of carrying thirty or mor...
INTVAL Path integral value
INU Inertial Navigation Unit
INVALID An indication that data from a device is bad and cannot be trusted
INVERTED Flying upside down. Note that elevator and rudder seem to work backward from the ground, as elevator, aileron and rudder inputs are all based upon the...
IPG Inertial Navigation System
IPPL National (ICAO) Private Pilots License (AOPA internal abbreviation)
IR Instrument Rating
IRE Instrument Rating Examiner
ISA ICAO Standard Atmosphere
ITC Investment tax credit.
ITU International Telephone Union, refers to certain HF channels.
ITW Initial Training Wing (Ground School)
IVSI Instantaneous vertical speed indicator.
JAA Joint Aviation Authorities (CAA of Europe)
JABO (JAGDBOMBER) Bf 109s converted to carry 250Kg bombs and carry out nuisance raids. A very effective tactic.
JAGD GESCHWADER Luftwaffe day fighters
JAGDSCHLOSS Rotating long range early warning radar
JAR Joint Aviation Recommendation (as used in some JAA documents, reported false!)
JAR-1 JAR on Definitions and abbreviations
JAR-145 JAR on Approved Maintenance Organizations
JAR-147 JAR on Maintenance Training
JAR-22 JAR on Sailplanes and Powered Sailplanes
JAR-25 JAR on Large Airplanes
JAR-36 JAR on Aircraft Noise
JAR-APU JAR on Auxiliary Power Units
JAR-AWO JAR on All Weather Operations
JAR-E JAR on Engines
JAR-FCL JAR on Flight Crew Licensing
JAR-MED JAR on Medical
JAR-OPS JAR on Flight Operations
JAR-P JAR on Propellers
JAR-TSO JAR on Technical Standard Orders
JAR-VLA JAR on Very Light Airplanes
JERK Rate of change of acceleration, either scalar or vector, often with subscripts such as ENU or XYZ to denote the coordinate frame; time derivative of a...
JET PROP Describes aircraft using turbine engines to drive propellers.
JET STREAM A migrating stream of high-speed winds present at high altitudes.
JET-A1 Jet Fuel type A1
JOSTLE British airborne jamming device to disrupt enemy RT transmissions.
JPPL JAR-FCL Private Pilots License (AOPA internal abbreviation)
JSA Joint Steering Assembly (JAA)
JUG Nickname for the P-47
JURG Joint User Requirement Group
K Airspace Euro control Project Class K (all traffic known)
KALMAN FILTER A filter for putting together multiple data sources, of different types, to return an estimate better than any one source;
KALTINT Altitude integral advantage.
KAMMHUBER-LI RAF nickname for the zonal system of air defense set up by General Joseph Kammhuber.
KAMPF GESHWADER; Luftwaffe Bomber wing
KIAS Knots Indicated Air Speed; IAS, in knots.
KINT Path integral gain
KIT A Kit is an unassembled aircraft, it arrives as packages of parts it must be assembled, as opposed to an ARF; Almost Ready to Fly, which is mostly pre...
KITE means a framework, covered with paper, cloth, metal, or other material, intended to be flown at the end of a rope or cable, and having as its only sup...
KLA Reference Acceleration Gain.
KNICKEBEIN German radio beam/beams used to guide bombers to their targets.
KNOT One nautical mile/hour, which is about 1.15 stature miles/hour.
KNOWN ICING FAA certified to fly into icing conditions.
KORFU (FuG 351) German ground radar often used to produce fixes on the bombers H2S equipment.
KOSIF knots Indicated Air Speed.
KPH Kilometers/hour
KPI Key Performance Indicator (KPI)
KT(S) knots true air speed (KT)
KTAE Track angle error gain (KTAE)
KTAS Knots True Air Speed (KTAS). TAS, in knots.
KVSF Velocity error scale factor (KVSF)
KXTKD Cross track deviation gain (KXTKD)
KXTKR Cross track deviation rate gain (KXTKR)
KZSF Altitude error scale factor (KZSF)
L-BAND A radio frequency between 890 and 1550 MHz.
LAAS Local Area Augmentation System (LAAS)
LAHSO Land And Hold Short Operation. (to cross intersecting runway).
LANDING GEAR (LG) The assemblies this includes the wheels and the wheel struts.
LANDING GEAR EXTENDED SPEED the maximum speed an aircraft can be safely flown while the landing gear is extended
LANDING GEAR OPERATION SPEED the maximum speed at which landing gear can be extended or retracted safely.
LANDING SKID The rail type landing equipment used aircrafts which have no wheels.
LAPLACE TRANSFORM A mathematical relationship to model. A continuing function in the complex frequency domain (S-plane). Laplace transforms are usually used by systems ...
LARGE AIRCRAFT Aircraft of more than 12,500 pounds. Maximum certificated takeoff weight
LASER IRS An inertial reference system getting angular rate information by measuring doppler shift between two counter-rotating light beams.
LASER OBSTACLE AVOIDANCE/TERRAINAVOIDANCE SENSOR (OA/TA) A sensor that warns for long, thin objects (IE: like wires); it has at least a 20deg x 30deg FOV. Itis both velocity tracked and pitch stabilized; it ...
LAT Latitude
LATERAL Related to latitude; across an aircraft left to right
LATERAL AXIS The axis about which an aircraft pitches, extending out along each wing.
LATERAL CONTROL The ability to make an airplane roll, or turn around its long axis, according to its pilot`s wishes
LATERAL CUE A cue to control heading; lateral cyclic cue See Also: wheel cue,
LATERAL CYCLIC A flight control operated by moving left or right with hand in rotary-wing aircraft, primarily to control roll (heading); controls differential pitch ...
LATERAL CYCLIC CUE A lateral flight director cue for rotary-wing aircraft, primarily to control heading, by changing roll; Compare: wheel cue; Symbols: Gamma sub "LAT"; ...
LATERAL GUIDANCE Calculations for the lateral axis of the appropriate guidance modes. The control law lateral axis input data are: Cross Track Deviation, Cross Track D...
LATERAL STABILITY Stability about an airplane`s longitudinal (nose to tail) axis.
LATITUDE Position on earth, north or south of the equator; See Also: astronomical latitude, geocentric latitude, geodetic latitude; Symbols: Phi; Typical Units...
LBA Luftfahrt-Bundes-Amt (German CAA)
LBST Pounds of static thrust
LCD Liquid-crystal display.
LDA Landing Distance Available
LDG Landing
LEADING AND TRAILING EDGES The foremost and rearmost edges of a wing.
LEADING EDGE (LE) The very front edge of the wing or stabilizer. This is the edge that hits the air first.
LEAN Refers to carburetor setting. When an engine is run too lean it will overheat, causing damage, and likely an in flight engine failure. Tuning a carbur...
LEAN RUN This happens when an engine develops a lean condition. Possible causes are improper tuning, improper fuel choice, fuel foaming due to excessive vibrat...
LED Light-emitting diode.
LEG A segment of a flight plan; flight path between two waypoints
LEO Low Earth Orbit
LF ADF Low Frequency Automatic Direction Finding
LFR low-frequency radio range.
LH Left-hand
LI-R5 LI=Italy, R5=Restricted Area No. 5
LICHTENSTEIN (FuG 212) German air interception radar
LICHTENSTEIN SN-2 (FuG 220) AI search radar effective at 2 miles
LIFT Force created by an airfoil moving through atmosphere, perpendicular to the direction of motion.
LIGHTER-THAN-AIR AIRCRAFT aircraft that can rise and remain suspended by using contained gas weighing less than the air that is displaced by the gas
LIMITER A filter that passes the input to the output, except that the output is limited to a minimum value and a maximum value; Compare: rate limiter;
LIRL Low Intensity Runway Lights
LLWAS Low Level Wind Shear Alert System
LLZ Localizer (approach system)
LMB Light marker beacon.
LMM compass locator at middle marker
LNAV Lateral navigation guidance.
LOAD FACTOR The ratio of a specified load to the total weight of the aircraft. The specified load is expressed in terms of any of the following: aerodynamic force...
LOADING a.k.a wing loading. The load placed on the airfoil of a flying machine. In the case of an aircraft, this would be wing loading. Typically found by div...
LOC Localizer receiver and indicator.
LOCALIZER (LOC) Part of ILS that provides lateral deviations from a preset course;
LOGBOOK A pilot`s record of his flying achievements, including flight time, takeoffs, landings, and maneuvers mastered.
LOM compass locator at outer marker.
LONG Lateral Navigation (GLS)
LONGITUDE Position on earth, east or west of the prime meridian; Symbols: lambda; Typical Units: rad, deg;
LONGITUDINAL Related to longitude; lengthwise along the center line of an aircraft forward
LONGITUDINAL AXIS The axis about which an aircraft rolls, extending from nose to tail.
LONGITUDINAL CUE A cue to control pitch; longitudinal cyclic cue See Also: throttle cue,
LONGITUDINAL CYCLIC A flight control operated by moving fore or aft with hand in rotary-wing aircraft, primarily to control pitch (speed); controls differential pitch of ...
LONGITUDINAL CYCLIC CUE A longitudinal flight director cue for rotary-wing aircraft, primarily to control speed, by changing pitch; Compare: throttle cue; Symbols: Gamma sub ...
LONGITUDINAL GUIDANCE Calculations for the longitudinal axis of the guidance modes. The control law longitudinal axis input data are: Reference Acceleration, Reference Acce...
LONGITUDINAL STABILITY The characteristic of returning to the trimmed angle of attack after a displacement.
LOOKS PER MINUTE Scanning or sweep rate of a weather radar antenna.
LOOP A vertical circle in the air. The plane noses up, keeps rotating until it`s on its back, and then comes down and around to describe a vertical circle ...
LOP Line of position.
LORAN LOng RANge version of GEE
LORAN(-C) Long Range Navigation
LORAN-C Hyperbolic grid navigation system based upon measured time differences (TD) from pulse transmissions.
LOW FREQUENCY AUTOMATIC DIRECTIONFINDING (LF ADF) Equipment that determines bearing to a radio station on a low frequency band, usually the standard AM band;
LOW-PASS FILTER (LPF) A filter that allows frequencies below a cutoff frequency to pass while attenuating frequencies above the cutoff frequency; See Also: first-order filt...
LPF Low-pass filter
LRT Long range fuel tanks.
LRU Line replaceable unit
LS-D12 LS=Switzerland, D12=Danger Area No. 12
LSC Local Signaling Channel (VDL-4)
LT Local Time
LTE Long Term Exception (JAR-FCL)
LUBRICANT The agent used to aid in the reduction of friction between two parts. This term is used for many substances, which in turn are used in many different ...
LUFTWAFFE-HELFERINNEN . "BLITZ MAIDENS";. German female radar plotters.
LYC Avco-Lycoming (Engine mfr.)
M means mach number.
M$ Mega dollars (1`000`000 US dollars)
MAA maximum authorized IFR altitude.
MAC Mean Aerodynamic Chord
MACH NUMBER Ratio of airspeed to the local speed of sound (Mach 1 is the speed of sound under current atmospheric conditions); Symbols: M;
MAGNETIC VARIATION (MVAR, MAGVAR) Difference between true north and magnetic north, varying with position; magnetic variation drifts with time; Symbols: nu; Typical Units: rad, deg;
MAGNETING HEADING Heading of the aircraft relative to magnetic north; A Magnetic Heading Sensor provides this heading data. Symbols: psi sub M; Typical Units: rad, deg;...
MAGVAR Magnetic variation
MAHMOUD RAF night fighter operation conducted against Luftwaffe night fighters with a single mosquito joining the landing pattern
MAHWP Missed Approach Holding Waypoint
MAIN GEAR Also Main Landing Gear. The large, heavy-duty landing gear struts and wheels that support most of the weight of the airplane. They are usually under t...
MAINTENANCE Indicates device is in a maintenance mode; Values: non-maintenance, calibration, alignment, bore sight
MALS medium intensity approach light system.
MALSR medium intensity approach light system with runway alignment indicator lights
MAMMUT MAMMOTH. German long range radar with a range of up to 300Km.
MANDREL Airborne radar jamming device operating in the 85-135 MHz waveband to counter the Freya early warning system.
MAP Equipment that produces a map image; See Also: Digital Map Generator
MARKER BEACON (MB) Part of Instrument Landing System that signals crew members of distance to runway, consisting of three markers:. inner, middle, and outer;
MAS Map section of AIP
MAS UAC Maastricht Upper Airspace Center
MASP Minimum Aviation System Performance
MASSAGED Filtered, estimated, or derived, or some combination of the three
MASTER CAUTION A signal which indicates that one or more caution lights has been activated (from MIL-STD-1472D);
MASTER WARNING A signal which indicates that one or more warning lights has been activated (from MIL-STD-1472D);
MATSE ECAC Transport Ministers Meeting on the Air Traffic System in Europe
MATTSCHEIBE FOCUSING SCREEN. German name for the glow in the sky from searchlights, flares and fires against which the bombers were silhouetted.
MATZ Military ATZ
MAUW Maximum All-Up Weight
MAWP Missed Approach Waypoint
MAXIMUM PAYLOAD Maximum Zero Fuel Weight - (minus) Basic Operating Weight
MAYDAY The international radiotelephony distress signal. When repeated three times, it indicates imminent and grave danger and that immediate assistance is r...
MB Marker Beacon
MC Mission computer
MCA Minimum Controllable Airspeed. The speed below which your control surfaces do not generate sufficient lift to control the aircraft.
MCC Millibar (replaced by hPa)
MCI Mobile Communication Infrastructure
MCTR Military CTR
MCU Minimum configuration unit.
MD Medical Doctor
MDA Minimum Descent Altitude
MDAU Maintenance data acquisition unit.
MDF demonstrated flight diving speed.
MDH Major damage history.
ME Multi Engine
MEA Minimum Enroute Altitude
MEAN SEA LEVEL (MSL) The average height of the surface of the sea for all stages of tide; used as a reference for elevations throughout the U.S.
MEASURED Raw data converted to standard units; Compare: derived, estimated, filtered, raw, selected, smoothed
MEL Minimum Equipment List
MEO Medium Earth Orbit
MEP Member of Parliament
MERIDIAN RADIUS OF CURVATURE Radius of the earth in the east/west direction at a given position; Synonyms: earth radius north/south; Symbols: rho sub M; Typical Units: ft; Dimensi...
MET Multi Engine Piston
METAR Meteorological Actual Report (current weather)
MFD Multi Function Display
MH Magnetic Heading
MHP Mental Health Professional (or: psychologist)
MHZ Megahertz (1`000 kHz)
MICROLINE Trade name owned by Collins.
MIDDLE MARKET Marker beacon located where the center of the glide slope is 200ft above the runway
MIDRANGE The power band of an engine between idle and full throttle.
MIL Military
MILES FLOWN The miles (computed in airport-to-airport distances) for each inter-airport hop actually completed in domestic and international revenue services, sch...
MILK RUN Nuisance sorties over Berlin undertaken by Mosquitoes to activate the German air defense system
MILLENNIUM Codename for the first 1000 bomber raid on Cologne 30-31 May 1942.
MISSION COMPUTER (MC) Mission processor;
MISSION OBJECTIVES Goals to be accomplished during a specific mission, including flight plan, NRPs, legs, and a plan on how to accomplish these objectives; plan includes...
MISSION PROCESSOR (MP) A general purpose computer to host avionics software. Synonyms: mission computer;
MIXING Radios with mixing will take two or more controls and mix their output in relation to stick input. The number of channels that can be mixed, and the p...
MIXING ARM A specialized lever which has three or more pivots. The length between pivots will determine the proportion of the mix between two or more linkages.
MIXTURE Fuel to air mixture is determined by the needle valve on the engine carburetor.
MLS Microwave Landing System
MLW Microwave Landing System
MM Middle Marker
MMI Man-Machine Interface (see HMI)
MMO maximum operating limit speed.
MMR Multi-Mode Receiver
MNPS Minimum navigational performance specifications.
MOCA Minimum Obstacle Clearance Altitude
MOD Moderate
MODE Microwave Landing System
MODE-A A transponder which does not give the controllers altitude information
MODE-C A transponder and encoding altimeter which together give air traffic controllers altitude information
MODE-S A transponder which features unique identification per unit, the potential for low-speed up and down data links, and "selective interrogation" trigger...
MODIFIED EVEREST A standard model for computing earth data
MODING CURSOR A symbol on a display, moved by an operator much like arrow keys for menu selection, to select one of several options
MOGAS Motor Gasoline (Auto-Gas)
MOH Major overhaul
MON Motor Octane Number (aviation fuel rating)
MONICA RAF tail fighter-warning device effective up to 4 miles
MOONSHINE Radio jamming device used by RAF to deceive the Freya radars by returning their own signal in an amplified form giving the impression of a larger forc...
MOPS Minimum operational performance standard (RTCA)
MOT Ministry of Transport
MOTOR Any electric motor used in the aircraft. Examples are the servo motors, which move the servo arms, and thus the control surfaces. There are also kits ...
MP Mission processor
MPA Multi-Pilot Airplane
MPH Speed in Miles Per Hour. Like RPM, MPH is both singular and plural. You can go 1 MPH or 100 MPH. You do not go 100 MPH`s.
MRA minimum reception altitude.
MRVA Multi-Pilot Helicopter
MRW Maximum Ramp Weight
MSA Minimum Safe Altitude
MSG Message
MSL Mean sea level
MSP Maintenance Service Program. (Garret engine)
MT Mean Sea Level
MTOM Maximum Take-Off Mass
MTOW Maximum Take-Off Weight
MULTI-MODE RADAR (MMR) A Multi-Mode Radar is used for Terrain Following (TF) and Terrain Avoidance (TA), Ground Mapping (GM) and Air-to Ground Ranging (AGR). The TF mode sup...
MULTIFUNCTION DISPLAY (MFD) The third or fifth tube in an EFIS, it replaces the weather radar screen and displays radar data, navigation maps, checklists and other information.
MVA Minimum Vectoring Altitude
MVAR Magnetic variation
MZFW Maximum Zero-Fuel Weight
N Airspace Euro control project Class N (managed traffic only)
N(....) Country identifier for aircraft registered in USA
N/A not available or not applicable
NAA National Aviation Authority (generic term within JAA)
NABS Navigation Augmentation Broadcast Service (ICAO for GBAS)
NACELLE An enclosure on an aircraft.
NAP-OF-THE-EARTH FLIGHT Flight with a goal to remain close to the earth, usually below the height of surrounding trees and less than 100 ft above the terrain; Compare: terrai...
NARA professional trade association of 54 reputable business companies organized to promote the growth and public understanding of the aircraft resale indu...
NASA National Aeronautics and Space Agency (USA)
NAT North Atlantic Tracks.
NATIONAL AIRSPACE SYSTEM (NAS) The common network of US airspace; air navigation facilities, equipment and services, airports or landing areas; aeronautical charts, information and ...
NATO North Atlantic
NATS National Air Traffic Service (UK)
NATURAL FREQUENCY Standard engineering term See Also: second-order filter; Symbols: omega sub n; Typical Units: rad/s, Hz; Dimensions: 1/Time;
NAUTICAL MILE Measurement of distance. Equals 1.15 statute miles.
NAV Navigation Receivers
NAV/COM Navigation and communication radios combined in a single unit.
NAVAID Navigation Aid (Ground Radio Station for Navigation)
NAVIGABLE AIRSPACE airspace at and above the minimum flight altitudes prescribed by or under this chapter, including airspace needed for safe takeoff and landing
NAVIGATION A system, usually software, in which the primary purpose is to generate position relative to a coordinate frame, usually fixed earth frame, such as la...
NAVIGATION AID A device or process to help with navigation, such as a VOR station or a position update;
NAVIGATION REFERENCE POINT (NRP) A point, usually fixed in earth coordinates but possibly moving; Also, a basic guidance mode, providing lateral guidance to an NRP, either by course o...
NAXOS (FuG 227) German ground radar which produced fixes on H2S.
NAXOS 2 Airborne version of NAXOS.
NBAA IFR FUEL RESERVES Fuel for go-around at destination airport
NDB Navigation
NEAN North European ADS-B Network
NEAR MIDAIR COLLISION (NMAC) An incident associated with the operation of an aircraft in which the possibility of a collision occurs as a result of proximity of less than 500 feet...
NEEDLE VALVE This is used to tune the fuel to air mixture on the engine carburetor. On most engines, the needle is turned clockwise to lean the mixture, and counte...
NELS Northwest Europe Loran Steering Committee
NEPTUN (FuG 216-217-218) German warning device fro attack from the rear or alternatively, a night-fighter search radar.
NICAD (OR NICD) Nickel Cadmium battery. Rechargeable batteries which are typically used as power for radio transmitters and receivers.
NICKELLING Codename for leaflet dropping
NIGHT the time between the end of evening civil twilight and the beginning of morning civil twilight, as published in the American Air Almanac, converted to...
NIL Nothing, no information
NIMBY "Not In My Back-Yard"-Syndrome: "We need an airport but not here"
NITRO Abbreviation for nitro methane. The addition of nitro methane in fuel provides more power, and a smoother idle, thus making the engine easier to tune....
NITRO METHANE The addition of nitro methane in fuel provides more power, and a smoother idle, thus making the engine easier to tune. The nitro also makes an engine ...
NM Nautical Miles. One nautical mile = 1.15 statute miles = 6,080 feet.
NM, NMI Nautical Mile (1.852 km)
NMS Navigation management system.
NMU Navigation management unit.
NOISE Part of received data that is undesired, consisting of random sinusoidal terms added to a signal; Compare: offset, signal;
NON-DIRECTONAL BEACON (NDB) An L/MF or UHF radio beacon transmitting non directional signals whereby the pilot of an aircraft equipped with direction finding equipment can determ...
NON-SCHEDULED SERVICE Revenue flights, such as charter flights, that are not operated in regular scheduled service and all non revenue flights incident to such flights.
NONPRECISION APPROACH PROCEDURE a standard instrument approach procedure in which no electronic glide slope is provided
NOPT no procedure turn required.
NORMALIZER Function to restrict input to a specific range, such as restricting an angle alpha in radians so that -pi le alpha le +pi; angles usually require norm...
NOSAR No Search and Rescue required (Australia)
NOSE The front portion of a aircraft`s fuselage.
NOSE GEAR The strut and wheel that`s under the nose of some aircraft.
NOTAM Notice to Airmen
NOTAR No Tail Rotor
NPA Non-Precision Approach
NPO Non-Profit Organization
NPPL National (ICAO) Private Pilots License (AOPA internally used: IPPL)
NPRM Notice of Proposed Rule-Making (USA)
NRP Navigation reference point
NTSB National Transportation Safety Board. Investigates airplane accidents. Plays at most an advisory role in flightworthiness accreditation.
NVFR Night VFR
NVM Nonvolatile memory. Digital memory that retains information through system shutdown.
NW North-west
O/R on request
OA Obstacle avoidance
OACI Organisation de l`Aviation Civile Internationale (voir ICAO)
OAT Outside Air Temperature
OBERKOMMANDO WEHRMACHT (OKW) German Army General Staff HQ
OBOE RAF target-finding bombing aid using two transmitting stations CAT and MOUSE.
OBS Omni bearing Selector - part of a VOR receiver system, which allows the pilot to select a course to or from a VOR station
OBST Obstacle, obstruction
OBSTACLE AVOIDANCE (OA) Outside Air Temperature
OCD Operational Concept Document
ODIAC Operational Development of Initial Air/ground Data Communications
ODT Operational Requirements and Data Processing Systems Team
OEI one engine inoperative.
OFAC Office Fİdİrale de l`Aviation Civile (Swiss CAA - voir BAZL)
OFF Device is powered off (power switch is off; no response to communications) - no data and function is available.
OFFSET Part of received data that is undesired, consisting of a random, time-invariant term added to a signal; Synonyms: bias; Compare: noise, signal
OH Overhaul
OM Outer Marker
OMEGA A very-low-frequency navigation system
OMS Outer Marker Substitute (sort of a virtual OM)
ONC Operational Navigation Chart
OPERATE to use or authorize to use aircraft, for the purpose (except as provided in Sec. 91.13 of this chapter) of air navigation including the piloting of ai...
OPERATIONAL CONTROL with respect to a flight, means the exercise of authority over initiating, conducting or terminating a flight.
OPERATIONAL DEVIATION (OD) An occurrence where applicable separation minima, as referenced in the operational error definition below were maintained, but: (1) less than the appl...
OPERATIONAL ERROR (OE) An occurrence attributable to an element of the air traffic control system which results in less than the applicable separation minima between two or ...
OPERATIONS How well is equipment operating; Values: operational (all function and data is available), degraded (equipment has partially failed with some function...
OPS Operations (or Operating hours)
OPTICAL DIGITIZER Any device using a photo sensor that can convert analog information to digital code
ORD Operational Requirements Document
ORIENTATION Direction in reference to a coordinate frame
OUT Operational Training Unit
OUTER MARKER Marker beacon located 5-7mi from the end of the runway; See Also: marker beacon
OUTSIDE AIR TEMPERATURE (OAT) The temperature just outside the aircraft; Symbols: T; Typical Units: deg; Dimensions: Temperature
OVER-THE-TOP above the layer of clouds or other obscuring phenomena forming the ceiling
OVERIDE To alter selection made automatically by software
OVERSEAS AIR COMMERCE the carriage by aircraft of persons or property for compensation or hire, or the carriage of mail by aircraft, or the operation or navigation of aircr...
OVERSEAS AIR TRANSPORTATION the carriage by aircraft of persons or property as a common carrier for compensation or hire, or the carriage of mail by aircraft, in commerce: (1) Be...
OXY Oxygen system for passengers and crew
P/P per person, per passenger
PAN-PAN The international radio-telephony urgency signal. When repeated three times, indicates uncertainty or alert followed by the nature of the urgency.
PANS Procedures for Air Navigation Services (ICAO)
PAPI Precision Approach Path Indicator
PAR Precision Approach Radar - a ground-radar based instrument approach which provides both horizontal and vertical guidance
PARACHUTE a device used or intended to be used to retard the fall of a body or object through the air
PART Precision Approach Radar
PAST STATUS WORDS Status words that are logically combined over time (such as "and "ing or "or "ing) to provide history of what has been set in the past
PATH INTEGRAL GAIN (KINT) A guidance control law parameter, generated by the lateral guidance modes;
PATH INTEGRAL LIMIT (INTLIM) A guidance control law parameter, generated by the lateral guidance modes; Typical Units: rad;
PATH INTEGRAL VALUE (INTVAL) A guidance control law parameter, generated by the lateral guidance modes; Typical Units: ft; Dimensions: Length
PAX Passenger (s)
PAYLOAD WITH FULL FUEL Useful Load - (minus) Usable Fuel
PBH Power by the Hour. (Rolls Royce engines)
PBIT Periodic built-in-test
PC Positive Control. (Trade name for Mooney Aircraft wing leveler)
PCL Pilot Controlled Lighting (RWY Lights operated by Microphone)
PCM Pulse Code Modulation. A modified FM signal used in high end radios. The signal is coded by the transmitter, resulting in a cleaner signal.
PEAK This is the point at which a battery will no longer accept a charge, and converts the energy to heat. This is damaging to the battery pack, and potent...
PEAK CHARGER This type of charger will eliminate the guesswork. When the battery has reached peak, the charger reverts to a maintenance charge rate, which will not...
PEAK POWER OUTPUT The maximum transmitter power output measured over a short time; usually used to rate pulse transmissions.
PED Personal Electronic Devices (e.g. Walkman, Handy etc.)
PEDAL A flight control operated by pushing with feet, primarily to control yaw via the rudder in fixed-wing aircraft or thrust to tail rotor in rotary-wing ...
PEP Peak envelope power. A standard electronic rating of any AC source, including a radio transmitter
PERFECTOS RAF airborne radar used to home on the IFF equipment carried by the German night fighters.
PERIOD Time of a periodic process; 1/f where f is the sampling frequency; Symbols: T; Typical Units: s; Dimensions: Time.
PERIODIC A process that executes at a fixed rate; Compare: a periodic;
PERIODIC BUILT-IN-TEST (PBIT) Self tests running internal to a device as part of normal operation; Compare: initiated built-in-test;
PERSON an individual, firm, partnership, corporation, company, association, joint-stock association, or governmental entity. It includes a trustee, receiver,...
PERSONNEL LOCATING SYSTEM (PLS) A basic guidance mode, providing lateral guidance to a PLS transmitter from range and bearing inputs. Equipment that determines range and bearing to a...
PETAL Preliminary Euro control Trial Air/ground Data Link
PFCS Primary flight control system
PFF PATHFINDER FORCE. Small group of aircraft which, after finding the target, put down flares to guide the following bombers.
PGL Parlamentarische Gruppe fìr Luftfahrt
PHYSICAL DEVICE A piece of equipment, a subsystem; Synonyms: device
PIC Pilot in Command
PILOT DEVIATION (PD) The actions of a pilot which result in the violation of a Federal Aviation Regulation (FAR) or a North American Aerospace Defense Command (NORAD) Air ...
PILOT IN COMMAND (PIC) The pilot responsible for the operation and safety of an aircraft during flight time.
PILOTAGE Navigation by visual reference to landmarks.
PILOTED LIMULATION Real-time engineering simulation
PIPERACK British airborne jamming device
PIREP Pilot (weather) Report
PITCH Describes the fore and aft attitude of the aircraft. (Nose high or low in comparison to the ground.) Controlled by the elevator (s).
PITCH AXIS The airplane axis controlled by the elevator. Pitch is illustrated by holding the airplane at each wingtip. Raising or lowering the nose is the pitch ...
PITCH CUE Flight director cue to control pitch; in fixed-wing aircraft, a yoke cue; in rotary-wing aircraft, a longitudinal cyclic cue
PITCH RATE Rate of change of pitch; time derivative of pitch; Symbols: p; Symbols: theta dot; Typical Units: rad/s, deg/s; Dimensions: 1/Time;
PITCH SETTING the propeller blade setting as determined by the blade angle measured in a manner, and at a radius, specified by the instruction manual for the propel...
PITOT PRESSURE Total pressure
PLS Personnel Locating System
PLY Plywood
PNR Prior Notice Required
PNT Paint
POB Persons on Board
PONTOONS See Floats.
PORT Nautical usage adopted in aviation. The left side, as determined by an observer in the vehicle, when vehicle and observer are right side up, and obser...
POSITION Location, usually in fixed earth coordinates such latitude and longitude; location, either scalar or vector, often with subscripts such as ENU or XYZ ...
POSITION UPDATE To cause navigation sensors, devices, or algorithms to reset position to value known to be more accurate due to inaccuracies and drift in the devices ...
POSITIVE CONTROL The separation of all air traffic within designated airspace by air traffic control.
POST KLYSTRON German jamming device to counter H2S
POWER PANEL 12-volt distribution panel that provides correct voltage for accessories like glow-plug clips, fuel pumps and electric starters. Usually mounted on a ...
PP(L) Private Pilots License (general)
PPL A Private Pilots License Airplane
PPL H Private Pilots License Helicopter
PPL/IR Association of PPL holders with Instrument Rating
PPM Pulse Position Modulation. Another term for FM.
PPO Parts Per Million
PPP Public Private Partnership
PPR Prior Permission Required
PRC Performance Review Commission (Euro control)
PRECISION Measure of exactness, possibly expressed in number of digits, for example, computed to the nearest millimeter; Compare: accuracy
PRECISION APPROACH PROCEDURE means a standard instrument approach procedure in which an electronic glide slope is provided, such as ILS and PAR.
PRESENT STATUS WORDS Most recently reported status words
PRESSURE Barometric pressure
PRESSURE ALTITUDE Barometric altitude
PREVENTIVE MAINTENANCE means simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations. Prohibited area. ...
PRIMARY FLIGHT CONTROL SYSTEM(PFCS) The most basic part of the flight controls operated by a pilot, including wheel (fixed wing), yoke (fixed wing), cyclic (rotary wing), pedals (fixed w...
PRIMARY UNITS A standard set of four units to which all units can be resolved; primary units are Mass (M), Length (L), Time (theta), and Temperature (T); for exampl...
PRIME RADIUS OF CURVATURE Radius of the earth in the east/west direction at a given position; Synonyms: earth radius east/west; Symbols: rho sub P; Typical Units: ft; Dimension...
PRK Photo Refractory Keratomy (eye surgery)
PRNAV Precision RNAV (RNP-1 or less compliant)
PROP BALANCER Device designed to aid in the balancing of aircraft airplane propellers.
PROPELLER means a device for propelling an aircraft that has blades on an engine-driven shaft and that, when rotated, produces by its action on the air, a thrus...
PRR Performance Review Report
PSG Program Steering Group
PSI Pounds per square inch.
PSIA Pounds per square inch
PT Procedure Turn
PTT Push-to-talk (switch)
PULL-PULL A linkage set up using two rods or wires. One is pulled for one direction, the other is pulled for the other.
PULSE A transmission of very brief duration used to carry information by using time measurement or as a series of pulses representing code.
PUSH-PULL A linkage set up using two rods. One rod pushes, while the other pulls.
PVT Private (pilot certificate)
PW Pratt
QDM (Q-Code) for Homing Track to a Station
QDR private
QFE (Q-Code) for Air Pressure in hPa on Ground (airport elevation)
QGO (Q-Code) for Airport Closed
QNH (Q-Code) for Air Pressure in hPa calculated to MSL
QUAMGO Quasi-Monopoly Government Organization
QUATERNION A system of representing attitude by measuring angle of aircraft center line with respect to three orthogonal axes plus rotation about centerline; qua...
R Rating
R Research and Development
RA (1) Radio altitude; (2) Resolution advisory (TCAS)
RADAL Radio Altimeter
RADALT Radar Altimeter.
RADAR On-board weather radar.
RADAR ALTIMETER Device that senses aircraft`s height above the terrain. Different from normal (barometric) altimeter.
RADAR ALTIMETER (RADALT) Measures height above terrain. The altitude is monitored to provide a low altitude warning during TF operations and landing operations. It can also be...
RADAR ALTITUDE Height with respect to the terrain below (distance above closest dirt); Synonyms: above ground level; Symbols: h sub r; Typical Units: ft; Dimensions:...
RADAR ALTITUDE SELECT (RALTSEL) A basic guidance mode, providing vertical guidance to an operator selected radar altitude;
RADAR APPROACH CONTROL FACILITY(RAPCON) A terminal ATC facility that uses radar and non radar capabilities to provide approach control services to aircraft arriving, departing, or transiting...
RADIAL ERROR PROBABILITY (REP) A probability that a percentage of one-dimension measurements will lie on a radial (line) of given length, with the origin centered at truth or mean o...
RADIO MAGNETIC INDICATOR (RMI) An ADF-like display with a pair of pointers which might be attached to either VOR or ADF receivers
RADIO NAVIGATION Navigation relative to radio station, providing, for example, of relative bearing, range, lateral deviation, and glide slope; Examples include VOR, TA...
RADOME A detachable nose cone made of plastic-type material, used to cover and protect an airplane`s radar antenna.
RAF Resolution Advisory (TCAS)
RAIL runway alignment indicator light system.
RAIM Receiver autonomous integrity monitoring (GPS)
RALT SEL Radar altitude select
RAM Random Access Memory
RAMJET A type of jet engine with very few moving parts which consists of a specially shaped tube open at both ends.
RAMP An airfield parking lot for aircraft.
RAMROD A tactical bombing mission with fighter escort
RANGE (RNG) Standard aviation term Synonyms: distance; Symbols: r; Typical Units: ft, nmi - method of measurement dependent on use; Dimensions: Length;
RANGER Similar to Circus but usually a deep penetration operation
RANGING Act of determining a range
RATE LIMITER A filter that passes the input as the output, except that rate of change of the output is limited to a maximum absolute value; Compare: limiter;
RATE OF CLIMB (ROC) The speed at which an aircraft is gaining (or losing) altitude, usually measured in hundreds or thousands of FPM.
RATE OF ROLL A measure of the speed with which an airplane can turn around its long axis, or roll.
RATED 2 1/2 -MINUTE OEI POWER with respect to rotorcraft turbine engines, means the approved brake horsepower developed under static conditions at specified altitudes and temperatu...
RATED 30-MINUTE OEI POWER with respect to rotorcraft turbine engines, means the approved brake horsepower developed under static conditions at specified altitudes and temperatu...
RATED CONTINUOUS OEI POWER with respect to rotorcraft turbine engines, means the approved brake horsepower developed under static conditions at specified altitudes and temperatu...
RATED MAXIMUM CONTINUOUS AUGMENTEDTHRUST with respect to turbojet engine type certification, means the approved jet thrust that is developed statically or in flight, in standard atmosphere at...
RATED MAXIMUM CONTINUOUS POWER with respect to reciprocating, turbo propeller, and turbo shaft engines, means the approved brake horsepower that is developed statically or in flight...
RATED MAXIMUM CONTINUOUS THRUST with respect to turbojet engine type certification, means the approved jet thrust that is developed statically or in flight, in standard atmosphere at...
RATED TAKEOFF AUGMENTED THRUST with respect to turbojet engine type certification, means the approved jet thrust that is developed statically under standard sea level conditions, wi...
RATED TAKEOFF POWER with respect to reciprocating, turbo propeller, and turbo shaft engine type certification, means the approved brake horsepower that is developed stati...
RATED TAKEOFF THRUST with respect to turbojet engine type certification, means the approved jet thrust that is developed statically under standard sea level conditions, wi...
RATING means a statement that, as a part of a certificate, sets forth special conditions, privileges, or limitations
RAW Data taken directly from the sensor; Compare: derived, estimated, filtered, measured, selected, smoothed
RAYON ; Ground-based interference of KNICKEBEIN in night fighter control
RAZZLE Phosphorous coated wooden strips transported in water Razzles were designed to fire crops and forests but with negligible effect.
RB Relative Bearing (NAV)
RBAS Receiver Based Augmentation System (DGNSS/DGPS)
RBN radio beacon.
RCA Avionics mfr.
RCLM runway centerline marking.
RCLS runway centerline light system.
RCU Radio control unit.
RDF Radio Direction Finding. A name first used for what became Radar
RDX Powerful explosive first used in the Barnes Wallis bouncing bomb
REA Recommended Crossing Altitude
REAL TIME Time in a computational process which runs at the same rate as a physical process; for example, algorithms designed to run a fixed period t (filter ti...
REAL-TIME ENGINEERING SIMULATION(RTES) A simulator designed to test avionics algorithms with a pilot in the loop, consisting of a simulated cockpit, an aircraft model, sensor models, and al...
REASONABLENESS A test to determine if data is reasonable, for example, radar altitude must be positive, and two devices should return similar data within known limit...
REBECCA The airborne interrogator end of a two-part system using a ground beacon called EUREKA. Designed as a homing system for the identification of ground f...
RECEIVE To absorb rf energy
RECEIVER (RX) The radio unit in the airplane which receives the transmitter signal and relays the control to the servos. This is somewhat similar to the radio you m...
REDLINE For a given airplane, the airspeed above which it is unsafe to fly. Redlining the plane may over stress or even damage structural elements in the plan...
REFACC Reference acceleration
REFERENCE What must be achieved in order to match a plan; Synonyms: desired;
REFERENCE ACCELERATION (REFACC) A guidance control law parameter, generated by the longitudinal guidance modes; Typical Units: ft/s-squared, g; Dimensions: Length / Time-squared
REFERENCE ACCELERATION GAIN(KLA) A guidance control law parameter, generated by the longitudinal guidance modes; Typical Units: s; Dimensions: Time.
REFLEX If a wing has an airfoil that curves down from the high point, and then curves back up, it`s said to be "reflexed". Reflex is the size of that reverse...
REIL Runway End Identifier Lights
REJECT To disallow a position update, usually by an operator; Compare: accept
RELATIVE Applies to measurements, in a non-standard, moving reference, as opposed to fixed reference; Compare: absolute;
RELATIVE BEARING Angle from aircraft center line to bearing of the destination; Symbols: B sub R; Typical Units: rad, deg;
REMOTE TERMINAL (RT) Term defining role of a device on a MIL-STD-1553 bus as being a slave; Compare: bus controller;
REMOTE TERMINAL UNIT Signal Data Converter;
RENDEZVOUS To meet with another aircraft in the air, for refueling or other mission objectives
RENDEZVOUS APPROACH To approach a planned rendezvous point
REP Radial error probability
REPORTED Data from a device
REPORTING POINT means a geographical location in relation to which the position of an aircraft is reported. Restricted area. A restricted area is airspace designated ...
RESONANCE This is the vibration frequency of a rotating or moving object. When the resonance of many parts of a machine are in synch, the whole machine will vib...
RETRACT SERVO Specifically used for mechanical retracts. It is a non-proportional servo which only moves 180 degrees. That is to say this servo is either "off" (gea...
RETRACTS Short for retractable landing gear. Wheels and struts that fold up into the airplane to get them out of the air stream and present less resistance to ...
REVENUE Pertaining to activities for which remuneration is received by the carrier.
REVERSERS System for braking aircraft during landing roll.
RF Radio Frequency
RFI Request For Improvement Message (slot)
RFP Reglement ìber die Ausweise fìr das Flugpersonal
RFU Radio frequency unit.
RG Retractable landing gear.
RH Right-hand
RHUBARB Low-level tactical operation from cloud cover.
RIA Regulatory Impact Assessment
RIGHT THRUST Right yaw angle of the engine relative to the centerline of the airplane. Right thrust helps overcome the normal yaw tendency caused by the torque of ...
RIMS Remote Integrity Monitoring Station (?)
RING-LASER GYRO (RLG) A gyroscope based on a laser beam instead of a rotating mass, providing to same data as a gyroscope;
RINGED An engine which uses a piston with a piston ring. Compare to ABC or ABN. Best used in dusty environments, a ringed engine is less susceptible to damag...
RLG Ring-laser gyro
RM Regional Meeting
RMI Radio Magnetic Indicator
RMK Remark (s)
RMS Root mean square;
RNAV Area navigation device.
RNAV WAY POINT (W/P) a predetermined geographical position used for route or instrument approach definition or progress reporting purposes that is defined relative to a VO...
RNG Range
RNP Required navigation performance.
RNP-N Area Navigation
RNSS Radio Navigation Satellite Services
ROADSTEAD Anti-shipping strike by fighters. Codenamed ROVER in Coastal Command.
ROC Rate of Climb
ROCKET an aircraft propelled by ejected expanding gases generated in the engine from self-contained propellants and not dependent on the intake of outside su...
RODEO A general fighter sweep over occupied territory.
RODERICH German jamming device to counter H2S
ROLL AXIS The airplane axis controlled by the ailerons. Roll is illustrated by holding the airplane by the nose and tail. Dropping either wingtip is the roll mo...
ROLL CUE Flight director cue to control roll; in fixed-wing aircraft, a wheel cue; in rotary-wing aircraft, a lateral cyclic cue
ROLL RATE Rate of change of roll; time derivative of roll; Symbols: q; Symbols: phi dot; Typical Units: rad/s, deg/s; Dimensions: 1/Time;
ROM Read-only memory.
RON Research Octane Number (Auto fuel rating)
ROOT MEAN SQUARE (RMS) A statistical measure of data; the root of the mean of the square; for variables with mean of zero, the standard deviation is equal to the rms; Compar...
ROOT SUM SQUARE (RSS) A statistical measure of data; the root of the sum of the square; for a vector, its length is equal to the rss of its scalar elements; Compare: root m...
ROTARY WING A helicopter;
ROTATIONS PER MINUTE (RPM) A unit of measure for such things as engine speed.
ROTORCRAFT A heavier-than-air aircraft that depends principally for its support in flight on the lift generated by one or more rotors. Includes helicopters and g...
ROTORCRAFT-LOAD COMBINATION the combination of a rotorcraft and an external-load, including the external-load attaching mea
ROUTE SEGMENT a part of a route.
RPL Repetitive Flight Plan
RPM Revolutions Per Minute. How fast something turns. It is both singular and plural. An engine can turn one RPM, or 10,000 RPM, NEVER 10,000 RPM`s.
RPN Revolutions per Minute
RPPL Restricted PPL
RR Rolls Royce
RSO Route per State Over flown
RSS Root sum square;
RT Receiver-transmitter combined in a single line-replaceable unit.
RTA Remote Terminal Access (CFMU)
RTCA (formerly) Radio Technical Commission for Aeronautics, now RTCA Inc. RT(F), R/T Radio Telephony
RTCA, INC. An association of U.S. governmental and industry aeronautical organizations dedicated to advancing aeronautics through consensus and recommendations.
RTES Remote terminal
RTU Remote Terminal Unit
RUDDER The moveable portion of the vertical tail surface. The rudder controls the airplane around the yaw axis. Also used as a verb, meaning to angle the rud...
RUNWAY INCURSION Any occurrence at an airport involving an aircraft, vehicle, person, or object on the ground that creates a collision hazard or results in loss of sep...
RUNWAY XX Runways are numbered after magnetic compass points, minus the 1`s column (where North is 0, and 360, degrees).
RUSC RVSM User Support Cell
RVR Runway Visual Range
RVSM Reduced Vertical Separation Minimum
RW, RWY Runway
RXTX Receiver-Transmitter
S-PLANE Continuous complex frequency plane; S-plane is used in control systems engineering in the design of control laws See Also: Laplace transform;
S/N Signal-to-noise ratio
SALS short approach light system.
SAMPLING FREQUENCY Rate of a periodic process; 1/T where T is the period; Symbols: f sub s; Typical Units: Hz; Dimensions: 1/Time.
SAR Search and rescue.
SARP serial number
SAT Search and Rescue
SATCOM Satellite communications system.
SATNAV Satellite Navigation (generic)
SB Service Bulletin
SBAS Space (or Satellite) Based Augmentation System (DGNSS/DGPS/WAAS/EGNOS)
SC Stratocumulus
SCARECROWS Flares which British aircrews believed were being used by the Germans to deceive them into believing they were bombers in flames. In fact they were st...
SCHEDULED SERVICE Transport service operated pursuant to published flight schedules, including extra sections and related non revenue flights.
SCHR„GE-MUSIK SLANTED MUSIC. Upward firing 20mm cannons used in German night fighters.
SDC Signal Data Converter
SDU Satellite data unit.
SE Single-Engine
SEA LEVEL ENGINE a reciprocating aircraft engine having a rated takeoff power that is producible only at sea level
SEALION (SEEL–WE) the planned invasion of Britain in September 1940
SEAPLANE An airplane that has floats, or pontoons, attached to allow it to land on water.
SEARCH PATTERN Basic guidance mode; provides lateral steering guidance to fly an expanding square search pattern, creeping line search pattern, or sector search patt...
SECOND IN COMMAND a pilot who is designated to be second in command of an aircraft during flight time
SECOND-ORDER FILTER. A smoothing filter in which the output follows the input, only more slowly; It is usually implemented in software as a difference equation of period T...
SECTOR SEARCH A pattern of concentric arcs followed for searching the ground from an aircraft; Compare: creeping line search, expanding square search;
SEEBURG TISCH SEEBURG TABLE; Glass screen on which the German night fighter controllers plotted the course of the raid
SEL Single-Engine Land
SELCAL Selective Calling system (used primarily with HF)
SELECTED Measured data picked from one of many sensors; Selecting is the process of choosing the "best" parameter from multiple copies of that parameter, from ...
SELF TEST A test internal to a device
SEMI-CIRCLE A measure of angle, 1 semi-circle = pi rad = 180 deg; angles from physical devices are often reported in semi-circles in order to compress data
SENSOR A device that measures, receives, or generates data, for example, an INS, a FLIR, a map. See Also: Data Source Object
SENSOR FUSION/CORRELATION (SFC) Measure of convergence of sensor data
SEP Spherical error probability
SEPARATION MINIMA The minimum longitudinal, lateral, or vertical distances by which aircraft are spaced through the application of air traffic control procedures.
SERRATE ; RAF airborne radar used to home on the German night fighters` Lichtenstein bomber detection equipment.
SERVICE CEILING The altitude above sea level beyond which an airplane can no longer climb more than 30 m(100 ft) per minute.
SERVO The radio component which does the work of moving a control surface.
SERVO OUTPUT ARM The removable arm or wheel which bolts to the output shaft of a servo and connects to the pushrod.
SFC Sensor Fusion/Correlation
SFE Single-Engine Piston
SFTS Service Flying Training School
SG Sub-Group (of Euro control Working Groups)
SHIVER An airborne transmitter used to jam Wìrzburg radar
SHOT DOWN A "hit" that results in a crash landing. Sometimes caused by radios miles away.
SHOW unless the context otherwise requires, means to show to the satisfaction of the Administrator
SHP Shaft horsepower. (refers to turbine engines.)
SHUTDOWN To cease normal operations
SI Surveillance Identity (Code) - (Mode S Transponder)
SID Standard Instrument Departure
SIDESLIP ANGLE Symbols: beta; Typical Units: rad, deg;
SIGMET Significant Meteo (hazardous weather warning)
SIGNAL Part of received data that is desired; Compare: noise, offset
SIGNAL DATA CONVERTER (SDC) A device that converts unique signals to a standard protocol, usually MIL-STD-1553B; Synonyms: Remote Terminal Unit;
SIGNAL-TO-NOISE RATIO (SNR,S/N) A ratio of magnitude of a desired signal to the magnitude of the noise received with it; Typical Units: dB;
SIL Sachplan Infrastruktur Luftfahrt
SILVER CROWN Trade name owned by King Radio.
SIM Simulator
SIMPLEX Single frequency for both transmitting and receiving in communications; generally implies a push-to-talk function and verbal procedures.
SIMULATOR A computer program which uses a modified radio transmitter, and a graphic depiction of a aircraft and flying area. This is used to give aircraft pilot...
SINGLE SIDEBAND (SSB) A highly efficient form of radio transmission wherein information is carried on a sideband instead of the center carrier in order to gain range perfor...
SIP Slot Improvement Proposal Message
SIRO Simultaneous Intersecting Runway Operation
SITA Sociİtİ Internationale de Tİlİcommunication Aİronautique
SITUATIONAL AWARENESS Situational awareness provides the pilots with information relative to the current surroundings, such as other aircraft or threats in the immediate ar...
SL Sea Level
SLANT RANGE Direct line distance, not along the ground;
SLATS Moveable surfaces on the leading edge of the wing that help airflow in low-speed flight. They enable the wing to fly at lower airspeeds than without t...
SLAVED COMPASS North-seeking gyro-stabilized compass system. Technically superior to DG.
SLIP A maneuver where the airplane`s controls are used to make the fuselage fly at an angle to the line of flight. This causes a tremendous increase in dra...
SLOP Slop occurs when a control surfaces movement does not move the servo. Common cause is a worn linkage point or poor linkage setup.
SLOT A specially-shaped slot in the wing just behind the leading edge. This directs airflow from below to the top of the wing, and helps low-speed flight b...
SLOW ROLL A very slow version of the roll.
SLP Speed Limit Point
SM Statute Mile (1.609 km - ACHTUNG: Nicht See-Meile!)
SMALL AIRCRAFT aircraft of 12,500 pounds or less, maximum certificated takeoff weight
SMEL Single/Multi Engine Land
SMGCS Surface Movement Guidance and Control System
SMGS Surface Movement Guidance System
SMM Slot Missed Message
SMOH Since major overhaul.
SMOOTHED Data that is the result of conditioning a signal with a simple filter; Compare: derived, estimated, filtered, measured, raw, selected; smoothing is us...
SMOOTHING FILTER A filter to reduce quick changes of a signal by attenuating high frequencies; See Also: first-order filter, second-order filter, wash-out filter;
SMPI Time Since Major Periodic Inspection
SMS Short Message System (Mobile Telephone Feature)
SN Serial Number
SNAP ROLL A type of rolling maneuver that is very quick and violent. It`s basically a spin where the flight path is in any direction chosen by the pilot. Improp...
SNR Signal-to-noise ratio
SOLO Your first totally unassisted flight that results in a controlled landing.
SOUTH AMERICAN A standard model for computing earth data
SP Single Pilot
SPA Single Pilot Airplane
SPAN, ALSO "WINGSPAN" The widest straight-line distance between the two wingtips.
SPAR A principal section of the wing structure of an airplane, going from tip to tip.
SPECI Special Report (Meteo)
SPECIAL USE AIRSPACE (SUA) Airspace of defined dimensions identified by an area on the surface of the earth wherein activities must be confined because of their nature and/or wh...
SPECIAL VFR CONDITIONS meteorological conditions that are less than those required for basic VFR flight in controlled airspace and in which some aircraft are permitted fight...
SPECIAL VFR OPERATIONS aircraft operating in accordance with clearances within controlled airspace in meteorological conditions less than the basic VFR weather minima. Such ...
SPEED Scalar velocity;
SPEED BRAKES Large panels that fold out of the aircraft structure to provide a lot of extra drag to the air. They are not part of the wing structure, but are usual...
SPEED CUE Flight director cue to control speed; in fixed-wing aircraft, a throttle cue; in rotary-wing aircraft, a longitudinal cyclic cue
SPEED ERROR A basic output from guidance to flight director, indicating the difference between actual speed and desired speed; Symbols: DELTA V; Typical Units: ft...
SPERRY Avionics mfr
SPH Single Pilot Helicopter
SPHERICAL ERROR PROBABILITY(SEP) A probability that a percentage of three-dimension measurements will lie within a sphere of given radius, with the sphere centered at truth or mean of...
SPIC Student Pilot in Command (JAR-FCL)
SPIN A maneuver where one wing is stalled and the other is still flying. This causes the airplane to rotate around its middle while it descends at a high r...
SPINNER The bullet-shaped fairing on the nose of the airplane around the propeller. This smoothes the airflow around the propeller hub and also makes the airp...
SPLIT-S Basically a reverse Immelmann. The airplane rolls onto its back, and then the nose comes down to finish a 1/2-loop. The direction of flight is changed...
SPOH Since prop overhaul.
SPOILER A control surface on fixed-wing aircraft, usually mounted to the wings, that provides roll control and lift; Symbols: delta sub S; Typical Units: rad,...
SPOILER(S) Control surfaces on the wing that destroy lift. They "spoil" it. They are used on sail-planes because they can steepen the very flat glide of the airc...
SQUAWK A 4-digit (actually 4-octal-digit -
SQUITTER The transmission of a specified reply format at a minimum rate without the need to be interrogated (transponders)
SR Sunrise
SRJ Slot Improvement Proposal Rejection Message
SRR Slot Revision Request Message
SRS Standard Routing Scheme (ARN)
SS Sunset
SSALS simplified short approach light system.
SSALSR simplified short approach light system with runway alignment indicator lights.
SSCVR Solid state cockpit voice recorder.
SST Slot Start Time
STA Scheduled Time of Arrival
STAB Horizontal stabilizer, "smaller wing"
STABILITY COORDINATES Coordinates referenced to the air mass; Compare: body coordinates, earth coordinates;
STABILIZER A surface which increases the stability of a aircraft. Most aircraft have two stabilizers, the horizontal (stab) and vertical (fin), which are mounted...
STAFFEL Luftwaffe equivalent to a squadron.
STAGNATION PRESSURE Total pressure
STALL When the air flowing over the wing cannot produce enough lift to support the weight of the aircraft, it`s called a "stall". This can happen if the air...
STALL TURN The maneuver in which the aircraft is flown to a point at which the main wing is vertical, stalls, then is turned about the yaw axis to continue in a ...
STANDARD ATMOSPHERE the atmosphere defined in U.S. Standard Atmosphere, 1962 (Geopotential altitude tables)
STANDARD RATE TURN A turn of three degrees compass heading per second.
STANDARD UNITS Units commonly encountered for a particular quantity;
STAR Standard Arrival
STARBOARD Nautical usage adopted in aviation. The right side, as determined by an observer in the vehicle, when vehicle and observer are right side up, and obse...
STATE DATA Data that defines aircraft parameters, such as position, velocity, attitude; Some standard terms for state data include: Groundspeed vector, wind spee...
STATE-SPACE MODEL A mathematical relationship of a system in time using state variables, inputs, outputs, and constants; The state-space model is composed of n state va...
STATIC PRESSURE A measure of barometric pressure as if the sensor were not moving with respect to the air; Compare: total pressure; Symbols: p sub s; Typical Units: p...
STATION A structure on the ground, perhaps containing VOR or TACAN
STATUS An indicator of how well a system or subsystem is working
STATUS INDICATOR An binary indicator of a particular aspect of a device; status indicators are independent of each other; status indicators listed in this dictionary a...
STATUS WORDS Data words reported by devices to indicate status; Each bit is defined on a device-by-device basis. The number of words vary from device to device. St...
STC (1) Supplemental Type Certificate. (2) Sensitivity-time compensation. In weather radar, a technique and circuit for calibrating a display.
STD Supplemental Type Certificate
STDMA Self-Organizing Time Division Multiple Access (VDL)
STICK A control in the cockpit which controls the elevators (forward/back axis) and the ailerons (left/right axis).
STOL Short takeoff and landing ability.
STOP WAY an area beyond the takeoff runway, no less wide than the runway and centered upon the extended centerline of the runway, able to support the airplane ...
STRAP DOWN INERTIAL SENSOR Accelerometers mounted to a platform fixed to the aircraft; Compare: gimbaled inertial sensor
STRUT Basically this is a supporting member. A wing strut supports the wing, and goes from the fuselage to the wing. Cabane struts are on biplanes, and supp...
SUA Special Use Airspace (USA)
SUB-TRIM This is a trim function on many computer radios, allowing trim function during set-up, and still allowing the full trim function in flight.
SUMPS Points underneath each fuel tank to test for contamination like water or other debris.
SUN Sunday (MON-TUE-WED-THU-FRI-SAT-SUN-HOL)
SUPERCHARGED Method for increasing engine power.
SURFACE Related to surface of water;
SURVIVABILITY A survivability subsystem detects and counters hostile actions.
SVFR Special VFR
SWASH PLATE A device to control the pitch of rotors; on rotary-wing aircraft, the swash plate is controlled by a collective and a cyclic; Surface Wind Wave Motion...
SWC Significant Weather Chart
SWEPT-WING A wing in which both the leading and trailing edges are slanted backward, to reduce air resistance at high speed.
SWM SIP Wanted Message
SYNCH Engine Fan Synchronizer
SYNCHRO Any device capable of converting mechanical position into an analog electronic signal.
SYNTHESIZER Frequency synthesizer, an electronic circuit capable of generating multiple frequencies from a single crystal oscillator.
SYSTEM Applied to measurements, means the best value that the system can determine.
T / T tonne
T/O take-off
T/RS Thrust Reversers
TA Traffic advisory (TCAS)
TACAN Terrain avoidance
TACAN POINT-TO-POINT (TCNP) A basic guidance mode, providing lateral guidance to a point relative to a TACAN station by specified range and bearing;
TACHOMETER An optical sensor designed specifically to count light impulses through a turning propeller and read out the engine RPM.
TACT Transition Altitude
TACTICAL AIR NAVIGATION (TACAN) A basic guidance mode, providing lateral guidance to a TACAN station; Equipment that determines range and bearing to a radio station with a TACAN tran...
TAE Track angle error
TAF Terminal Area Forecast (weather forecast)
TAIL DRAGGER The nickname of an airplane that sits on its tail with the two main wheels in front and a tail wheel in the rear.
TAIL WHEEL The small wheel at the tail of the airplane. This is found on the type of airplane that has the two large wheels in the front, and the small one in th...
TAILSKID On old World War I type aircraft, or pioneer-type aircraft, there was no tail wheel. A wooden skid was used to support the tail of the airplane. While...
TAKEOFF POWER (1) With respect to reciprocating engines, means the brake horsepower that is developed under standard sea level conditions, and under the maximum con...
TAKEOFF SAFETY SPEED a referenced airspeed obtained after lift-off at which the required one-engine-inoperative climb performance can be achieved
TAKEOFF THRUST "", with respect to turbine engines, means the jet thrust that is developed under static conditions at a specific altitude and atmospheric temperature...
TARGET Object or point pointed by FLIR or radar
TARGET CURSOR A symbol on a display, moved by a track handle or similar device, to select objects on the display
TAS True airspeed
TAUT LINE Basic guidance mode; provides vertical guidance to maintain a taut line for a dipping sonar, or other such device.
TAWS Terrain Awareness and Warning System
TAXI The movement of an airplane under its own power on the surface of an airport.
TAXIWAY A road leading from the airplane parking area to the runway; always marked with yellow lines.
TBO Time between overhaul
TC True Course
TCAS Traffic alert and Collision Avoidance System
TCH Threshold Crossing Height
TCN Tacan
TCNP Tacan Point-to-Point
TDMA Time Division Multiple Access (VDL)
TDZL touchdown zone lights.
TECHNICAL STANDARD ORDER (TSO) A performance specification and production compliance criteria applied to avionics and defined by FARs and the RTCA.
TERMINAL RADAR SERVICE AREA(TRSA) Airspace surrounding designated airports wherein ATC provides radar vectoring, sequencing, and separation on a full-time basis for all IFR and partici...
TERRAIN The contour of the earth;
TERRAIN AVOIDANCE (TA) Flight such that the aircraft maintains a constant barometric altitude but flies around obstacles; Compare: obstacle avoidance, threat avoidance;
TERRAIN FOLLOWING (TF) A basic guidance mode, providing vertical guidance to maintain an operator selected radar altitude above the terrain. Flight such that the aircraft tr...
TERRAIN REFERENCED NAVIGATION(TRN) A navigation mode based on comparison of barometric altitude and radar altitude with a map; Kalman filters correlate the terrain data and the altitude...
TEST STATUS WORDS Status words reported at the conclusion of a test. Values: test in progress, not tested, normal, redundant, degraded, failed;
TF Terrain following;
TGL Task Force
TH True Heading
THA Threat avoidance
THR Threshold
THREAT AVOIDANCE (THA) Flight cues designed to avoid enemy threats, such as anti-aircraft artillery and aircraft; Compare: obstacle avoidance, terrain avoidance;
THROTTLE The control that allows the pilot to change the speed of the engine. In a car, the "gas pedal" is actually the throttle control for the car.
THROTTLE CUE A longitudinal flight director cue for fixed-wing aircraft, primarily to control speed, by changing power; Compare: longitudinal cyclic cue; Symbols: ...
THRUST The forward force provided by the airplane`s engine. This is the force that drives the airplane forward
TILT ROTOR An aircraft with tilting rotors for fixed-wing flight or rotary-wing flight;
TIM Time (Euro control, everybody else is able to add an "e")
TIME CONSTANT Constant for a first-order filter determining time at which the output of the filter reaches nearly 0.6321 percent of a step input; Symbols: tau; Typi...
TIME IN SERVICE with respect to maintenance time records, means the time from the moment an aircraft leaves the surface of the earth until it touches it at the next p...
TINSEL RAF airborne jamming device used by wireless operators to transmit engine noise over the German night fighter control frequencies
TIS-B Traffic Information System-Broadcast
TKE Track error
TKOF Take-Off
TLS Transponder Landing System
TMA Terminal (Control) Area
TMG Touring Motor Glider
TNC Tactical Navigation Chart
TOLERANCES Allowed error in measurements
TORQUE The force which tends to cause rotation.
TOTAL PRESSURE A measure of barometric pressure in the moving air; Synonyms: dynamic pressure, Pitot pressure, stagnation pressure; Compare: static pressure; Symbols...
TOWER A terminal facility that uses air/ground communications, visual signaling, and other devices to provide ATC services to aircraft operating in the vici...
TPC Tactical Piloting Chart
TPIA Transition Plan for Implementation of Airspace Strategy
TR Abbreviation for Torque Roll, a 3D maneuver which begins as a hover and the torque of the engine/propeller rotates the aircraft in a counterclockwise ...
TRACK (TRK) A basic guidance mode, providing lateral guidance to an operator selected ground track;
TRACK ANGLE ERROR (TAE) A guidance control law parameter, generated by the lateral guidance modes; Typical Units: rad;
TRACK ANGLE ERROR GAIN (KTAE) A guidance control law parameter, generated by the lateral guidance modes;
TRACK HANDLE A device to move a cursor in two axes on a display, much like a mouse
TRACKING Tracking is performed by the TRN
TRAFFIC COLLISION AVOIDANCESYSTEM (TCAS) TCAS-I provides warnings (TAs) of other nearby aircraft; TCAS II provides warnings and resolutions advisories (RAs), and coordinates RAs with other TC...
TRAFFIC PATTERN The traffic flow that is prescribed for aircraft landing at, taxiing on, or taking off from, an airfield.
TRAILING EDGE (TE) The rearmost edge of the wing or stabilizer
TRAINER AIRPLANE A aircraft designed to be inherently stable and fly at low speeds, to give first-time air crafters time to think and react as they learn to fly.
TRANSCEIVER Type Rating
TRANSCEIVERS A device that receives and transmits
TRANSIENT-FREE SWITCH A switch with a wash-out filter so that the output contains no transients (steps) at switch time
TRANSMIT To radiate RF energy
TRANSMITTER A device that transmits
TRANSMITTER (TX) The hand-held radio controller. This is the unit that sends out the commands that you input.
TRANSPONDER Transmitter-Responder
TRANSPONDER (TX) A receiver/transmitter which will generate a reply signal upon proper interrogation; the interrogation and reply being on different frequencies.
TRE Type Rating Examiner
TREND MONITORING Continuous computerized observation of turbine engine performance. Used to detect early sings of wear.
TRI Type Rating Instructor
TRICYCLE GEAR The landing gear arrangement where the airplane has main gear and a nose gear.
TRIM To adjust an aircraft`s trim tabs and thereby relieve the pressure required on the controls to keep the nose in the desired position.
TRIM TAB A secondary control surface, usually mounted to primary control surface such as aileron, elevator, rudder, or stabilizer, that controls the position o...
TRK Track
TRN Terrain Referenced Navigation;
TRN-INS TRN with INS
TRTO Type Rating Training Organization
TRUE Best available estimate, such as true airspeed; referenced to true north, such as true heading;
TRUE AIRSPEED the airspeed of an aircraft relative to undisturbed air. True airspeed is equal to equivalent airspeed multiplied by (0/)1/2.
TRUE AIRSPEED (TAS) The airspeed of an aircraft relative to undisturbed air.
TRUE BEARING Symbols: B sub T; Typical Units: rad, deg;
TRUE HEADING Heading of the aircraft relative to true north; Symbols: psi sub T; Typical Units: rad, deg;
TRUE TRACK Ground track angle; Symbols: T sub T; Typical Units: rad, deg;
TSC Total Time Since CORE
TSMO Time since major overhaul
TSN Time Since New (also TTSN)
TSO Technical Standard Order
TT Total Time Airframe
TTG, TTS OR TTW Time to go, time to station, time to waypoint.
TUBA a jamming device for Freya radar operating in the 70-200 MHz range
TUNE To set the operating frequency or channel for a device
TURBO PROP Is said of an airplane powered by a type of jet engine, the turbo prop, equipped with a turbine-driven propeller.
TURBOJET AIRCRAFT An aircraft having a jet engine in which the energy of the jet operates a turbine which in turn operates the air compressor.
TURBOPROP AIRCRAFT An aircraft having a jet engine in which the energy of the jet operates a turbine which drives the propeller.
TURBULENCE MODE Flight control system mode in which a "softer" response to gust upsets is programmed.
TVOR very high frequency terminal omni range station.
TWR Tower (Control Tower)
TYPE (1) As used with respect to the certification, ratings, privileges, and limitations of airmen, means a specific make and basic model of aircraft, incl...
U Airspace Euro control project Class U (unknown traffic)
U/S unserviceable
U/V ADF UHF/VHF Automatic Direction Finding
UAT Universal Access Transceiver
UAV Unmanned (or Uninhabited) Aeronautical (or Aerial) Vehicle
UFN Until Further Notice
UFO Unidentified Flying Object
UHF Ultra High Frequencies (300 MHz-30 GHz)
UHF/VHF AUTOMATIC DIRECTIONFINDING (U/V ADF) An Automatic Direction Finder that determines relative bearing to a transmitter to which it is tuned, in either the UHF band or VHF band;
UL Ultra light, Ultra-lİger motorisİ
ULM Ultra light, Ultra-lİger motorisİ
ULTRALIGHT VEHICLE An aeronautical vehicle operated for sport or recreational purposes which does not require FAA registration, an airworthiness certificate, nor pilot c...
UMAS Unmanaged Air Space (Euro control Definition)
UNDER CAMBER This means that the lower surface of the wing has a hollow curve when observed from front to back. A thin wing with a high camber will be under camber...
UNDERCARRIAGE STRUT A part of an airplane`s structure, designed to resist distortion, which supports the landing gear.
UNIT FUNCTIONS A collection of functions used as standard test cases in control systems engineering; The primary unit functions of interest in avionics are the unit ...
UNIT IMPULSE A function used as a standard test case in control systems engineering; a spike of "area" one at time t = 0; Synonyms: impulse; See Also: unit functio...
UNIT LESS No units, such as ratios; a quantity with standard units of 1; a quantity with primary units of 1; Synonyms: dimensionless;
UNIT RAMP A function used as a standard test case in control systems engineering; a line of slope 1 starting at zero at time t = 0; Synonyms: ramp; See Also: un...
UNIT STEP A function used as a standard test case in control systems engineering; a step from zero to one at time t = 0; Synonyms: step; See Also: unit function...
UNITED STATES in a geographical sense, means (1) the States, the District of Columbia, Puerto Rico, and the possessions, including the territorial waters, and (2) t...
UNITED STATES AIR CARRIER a citizen of the United States who undertakes directly by lease, or other arrangement, to engage in air transportation.
UNITS A standard quantity, such as ft or mi; Synonyms: dimension;
UNIVERSAL TRANSVERSE MERCATOR(UTM) A system of fixed earth coordinates, sometimes used instead of latitude and longitude, accurate relative to others close by, such as ground troops;
UPDATE A process by which position is reset with a known better position; updates occur at the data source level or at the physical device level, depending u...
UPKEEP Codename for Barnes Wallis` bouncing bomb used in the Dambusters` raid
URB User Relations Bureau (CFMU)
USABLE FUEL (LBS) Usable fuel (gallons) x 6.7 lbs/gallon
USAF US Air Force
USEFUL LOAD Maximum Ramp Weight - (minus) Basic Operating Weight
USG (AL) US-Gallon (3.78 Liter)
UTC Universal Coordinated Time.
UTM Universal Transverse Mercator
V Universal Time Coordinated
V (X) Speed for best angle of climb.
V (Y) Speed for best rate of climb.
V1 speed for best angle of climb.
VA Maneuvering Speed (max. structural speed allowed for full control deflection)
VAC Volts alternating current.
VAL Visual Approach and Landing (Chart)
VAR Variation
VASI Visual Approach Slope Indicator
VAT Value Added Tax
VB design speed for maximum gust intensity.
VC design cruising speed.
VD Max. Dive Speed (for certification only)
VDB VHF Data Broadcast
VDC Volts direct current.
VDF demonstrated flight diving speed.
VDL VHF Data Link (-n = type n)
VEF the speed at which the critical engine is assumed to fail during takeoff.
VEHICLE/PEDESTRIAN DEVIATION(VPD) An entry or movement on an airport movement area by a vehicle operator or pedestrian that has not been authorized by air traffic control (includes air...
VELOCITY Rate of change of location, either scalar or vector, often with subscripts such as ENU or XYZ to denote the coordinate frame; time derivative of posit...
VELOCITY EAST Aircraft velocity in true east direction; Symbols: V sub E; Typical Units: kt, ft/s; Dimensions: Length / Time;
VELOCITY ERROR SCALE FACTOR(KVSF) A guidance control law parameter, generated by the longitudinal guidance modes;
VELOCITY NORTH Aircraft velocity in true north direction; Symbols: V sub N; Typical Units: kt, ft/s; Dimensions: Length / Time;
VENTRAL FIN A small vertical surface on the bottom of the aft fuselage. Usually a long, slim triangle that is narrow at the front, and widens toward the rear. It ...
VERT SPD Vertical speed hold
VERTICAL Reference to earth radial, for example, vertical velocity is velocity along earth radial; See Also: East-North-Vertical;
VERTICAL ACCELERATION Aircraft acceleration in earth vertical direction; Symbols: A sub V; Typical Units: ft/s-squared, g; Dimensions: Length / Time-squared;
VERTICAL CUE A cue to control altitude; See Also: yoke cue, collective cue;
VERTICAL GUIDANCE Calculations for the vertical axis, rather than the longitudinal axis. The control law vertical axis input data are: Desired Altitude, Altitude Integr...
VERTICAL SPEED HOLD (VERT SPD) A basic guidance mode, providing vertical guidance to maintain an operator selected vertical speed;
VERTICAL SPEED INDICATOR (VSI) An onboard instrument which gauges rate of climb or descent, in feet per minute.
VERTICAL VELOCITY Aircraft velocity in earth vertical direction; Symbols: V sub V; Typical Units: ft/s; Dimensions: Length / Time;
VF design flap speed.
VFE Max. Flaps Extended Speed
VFR Visual Flight Rules ("good" weather operations rules)
VFR OVER-THE-TOP with respect to the operation of aircraft, means the operation of an aircraft over-the-top under VFR when it is not being operated on an IFR flight pl...
VH maximum speed in level flight with maximum continuous power.
VHF Very High Frequency radio equipment.
VHF OMNI RANGE (VOR) Equipment that determines bearing to a radio station with a VOR transmitter; VOR transmitters usually contain ILS transmitters in addition to VOR; A b...
VILLAGE INN A gun laying radar installed in the rear-turret of some Lancaster bombers allowing blind-firing on an "illuminated" target
VIS Very High Frequency (30-300 MHz)
VISUAL FLIGHT RULE (VFR) Rules that govern the procedures for conducting flight under visual conditions (VMC). The term is also used in the United States to indicate weather c...
VISUAL METEOROLOGICAL CONDITIONS(VMC) Meteorological conditions expressed in terms of visibility, distance from clouds, and ceiling equal to or better than specified minima.
VJAR-FCL Verordnung JAR-FCL (JAR-FCL transformed to Swiss Law)
VLA Very Light Aircraft (Aircraft certification category)
VLE Max. Landing Gear Extended Speed
VLF Very Low Frequency radio equipment
VLO Max. Landing Gear Operation Speed
VLOF lift-off speed.
VMC Visual Meteo Conditions ("good" weather for VFR or IFR)
VMO maximum operating limit speed.
VMU minimum unstick speed.
VNAV Vertical navigation, or the capability to compute pitch-axis maneuvers and altitude-related points in space.
VNE Never Exceed Speed
VNO Max. Structural Cruising Speed
VOR A ground-based electronic navigation aid transmitting very high frequency navigation signals, 360 degrees in azimuth, oriented from magnetic north. Us...
VOR/DME Vertical Navigation (GLS)
VORTAC VHF Omni range;
VR Rotation Speed
VS the stalling speed or the minimum steady flight speed at which the airplane is controllable.
VS0 Stalling Speed Landing Config
VS1 Stalling Speed in a specified Config.
VSSE Minimum Safe Single Engine Speed
VTOSS takeoff safety speed for Category A rotorcraft.
VX Best Angle of Climb Speed
VXSE Best Angle of Climb Speed, 1 engine inoperative
VY Best Rate of Climb Speed
VYSE Best Rate of Climb Speed, 1 engine inoperative
WA (IAOPA) World Assembly
WAAS GNSS wide-area augmentation system.
WANGANUI Colored flares dropped on H2S to sky mark a target
WARNING A signal which alerts the operator to a dangerous condition requiring immediate action (from MIL-STD-1472D); an annunciator that is the most critical ...
WARNING, CAUTION, ADVISORY (WCA) See: warning, caution, advisory, annunciator, alert;
WASH-OUT FILTER A filter to smooth a transition due to change of input source, such as when changing modes; See Also: transient-free switch;
WASHOUT The twist in an airfoil which causes less angle of attack at the tips than the root. For airplanes, this increases stability of the aircraft at slow s...
WASSERMANN German long range radar with a range of up to 190 Km.
WAYPOINT A predetermined geographical position used for route/instrument approach definition, or progress reporting purposes, that is defined relative to a VOR...
WAYPOINT (WYPT) A point on the ground, predefined as a point of interest for the flight; a basic guidance mode, providing lateral guidance to a waypoint, either by co...
WAYPOINT APPROACH To approach a waypoint
WCA Warning, Caution, Advisory
WEATHERVANE This describes the tendency to point into the wind. Stabilizers on a aircraft result in its desire to weathervane.
WEIGHT ON WHEELS (WOW) Indication of whether the aircraft has weight on its wheels, meaning airborne or on the ground; weight on wheels can be detected by a sensor on the wh...
WET WINGS Method for containing fuel in wings without using rubber fuel cells.
WGS-84 Wide Area Augmentation System
WGS72 World Geodetic Survey 1972
WGS84 World Geodetic Survey 1984
WHEEL A flight control operated by turning with hands in fixed-wing aircraft, primarily to control roll (heading) via the ailerons; wheel is connected to yo...
WHEEL CUE A lateral flight director cue for fixed-wing aircraft, primarily to control heading, by changing roll; Compare: lateral cyclic cue; Symbols: Gamma sub...
WHEEL PANTS The large fairings used to streamline the wheels of an aircraft that has non-retracting, or "fixed" landing gear (so-called because it`s "fixed" in pl...
WHITE BOMBS Nickname for propaganda leaflets.
WILDE SAU WILD BOAR. German ground- controlled night fighter system using twin engined aircraft
WIMPY RAF nickname for the Vickers Wellington bomber. The name came from J. Wellington Wimpy, a character in the Popeye cartoon in the Daily Mirror
WIMS System Wide Information Management
WIND BEARING Symbols: B sub W; Typical Units: rad, deg;
WIND SPEED Symbols: V sub W; Typical Units: kt, ft/s; Dimensions: Length / Time;
WINDOW Strips of silver paper dropped by British aircraft to confuse the German ground radars
WINDSOCK This can be used to describe a number of devices, all of which give a visual clue to the direction and speed of wind in a given location.
WING The main lifting surface of an airplane.
WING FENCE Term preferred by Airbus and McDonnell-Douglas aircraft manufacturers for the vertical structures at the outside ends of the wings of some of their je...
WING LOADING This is the amount of weight per square foot that has to be overcome to provide lift. It is normally expressed in ounces per square foot. This specifi...
WING ROOT The centerline of the wing, where the left and right wing panels are joined.
WINGLET A small vertical surface at the tips of the wings. They help direct the turbulent airflow that all wings have at the tips. They makes the wings more e...
WIP Work in Progress
WMO World Meteorological Organization
WORLD GEODETIC SURVEY 1972 (WGS72) A standard model for computing earth data;
WORLD GEODETIC SURVEY 1984 (WGS84) A standard model for computing earth data;
WOW Weight on wheels
WP Waypoint
WPT Waypoint
WRAP TEST A test to send data to a device having it sent back unaltered
WWII Waypoint
WX Weather
WYPT Waypoint
WœRZBURG German short (11 mile) range gun laying radar capable of giving both height and range.
X-BAND Frequency range in which most general aviation weather radars operate.
X-BEAMS German radio beams used to guide their bombers to the target
XPDR Transponder. Radar-enhancement/data link box for ATC purposes.
XPOND Transponder
XTK Cross track; cross track error.
XTKD Cross track deviation
XTKR Cross track deviation rate
XYZ A standard aircraft coordinate frame and sign convention, where nose, right wing, and down are positive X, Y, and Z, respectively; often used as subsc...
Y-BEAMS German radio beams used to guide their bombers to the target
Y-SERVICE British organization for the interception and reporting of German wireless "chatter" for intelligence purposes.
Y2K Year-2000 (computer date problem) NOTE: k=decimal kilo=1000 (1-1000); thus Y2k=2000 K=binary kilo=1024 (0-1023); thus Y2K=2047
YAW The nose-left and nose-right movement of the airplane. This is controlled by the rudder.
YAW AXIS The airplane axis controlled by the rudder. Yaw is illustrated by hanging the airplane level by a wire located at the center of gravity. Left or right...
YAW RATE The rate of movement about the vertical axis of a aircraft.
YOKE CUE A vertical flight director cue for fixed-wing aircraft, primarily to control altitude, by changing pitch; Compare: collective cue; Symbols: Gamma sub ...
Z Infra-red identification equipment
Z TRANSFORM A mathematical relationship to model a discrete function in the complex frequency domain (Z-plane); Z transforms are commonly used by systems engineer...
Z-BEND A type of linkage point using a bend in the control rod which resemble a Z.
Z-PLANE Discrete complex frequency plane; Z-plane is used in control systems engineering in the design of control laws See Also: Z transform;
ZAHME SAU TAME BOAR. German "free lance" night fighter system using single engined aircraft
ZERST–RER GESHWADER Luftwaffe Destroyer Wings, composed of Bf110 Heavy fighters
ZOC Zone of confusion
ZONE OF CONFUSION (ZOC) A circular area centered at a TACAN station in which bearing is extremely noisy;
ZULU Greenwich Mean Time, also known as Universal Coordinated Time.


  © 2003 Aviation Terms.com