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.
