Glossary of Aviation Terminology

A , B , C , D , E , F , G , H , I , J - K , L , M , N , O , P , Q - R , S , T , U , V, W, X - Z

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

PBIT: Periodic built-in-test

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 aircraft; pedals are automatically controlled in modern aircraft;

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: aperiodic;

Periodic built-in-test (PBIT): Selftests running internal to a device as part of normal operation; Compare: initiated built-in-test;

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 personnel with a PLS transmitter; Provides range and bearing to locate ground personnel. Coded continuous or periodic interrogations of the portable ground radios are used to provide the information.

PFCS: Primary flight control system

Physical device: A piece of equipment, a subsystem; Synonyms: device

Piloted simulation: Real-time engineering simulation

Pitot pressure: Total pressure

Pitch: The angle of a rotor measured in the plane of rotation; Symbols: theta,Theta; Typical Units: rad, deg;

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;

PLS: Personnel Locating System

Position: Location, usually in fixed earth coordinates such latitude and longitude; location, either scalar or vector, often with subscripts such as ENU or XYZ to denote source or coordinate frame; time integral of velocity; Symbols: p,P,x,y,z; Typical Units: ft,nmi; Dimensions: Length;

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 and algorithms

Precision: Measure of exactness, possibly expressed in number of digits, for example, computed to the nearest millimeter; Compare: accuracy

Present status words: Most recently reported status words

Pressure: Barometric pressure

Pressure altitude: Barometric altitude

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 wing and rotary wing), throttle (fixed wing), and collective (rotary wing);

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 example, standard units for velocity might be kt (nmi/hr), ft/s, m/s, mph, but primary are always Length / Theta; sometimes written with negative subscripts.

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; Dimensions: Length;

A , B , C , D , E , F , G , H , I , J - K , L , M , N , O , P , Q - R , S , T , U , V, W, X - Z