Aviation Definitions

Some of the most common terms or acronyms used in Aviation Navigation

** definitions extracted from Wikipedia. Visit Wikipedia.com for additional details.

CRAFT stands for

i.e: Cleared to Halifax via flight plan route, Climb to 5000, expect vectors, Contact Departure on 125.80, Squawk 3156

VOR - VHF Omni-directional Radio Range
is a type of radio navigation ... low/medium frequency ranges and beacons in civilian aviation

ADF - Automatic Direction Finder

is a marine or aircraft radio-navigation instrument which automatically and continuously displays the relative bearing from the ship or aircraft to a suitable radio station. ADF receivers are normally tuned to aviation or marine NDBs operating in the LW band between 190 - 535 kHz.

DME - Distance Measuring Equipment

is a transponder-based radio navigation technology that measures distance by timing the propagation delay of VHF or UHF radio signals.


is a virtual navigational fix that helps aircraft to maintain their flight plan. It is usually defined as the intersection (in the geometrical sense) of two VOR radials.

Intersections also play an important role in departure and approach procedures. All intersections have an alphabetical or alphanumeric designation. Near major airports, the intersection designation code typically consists of three letters followed by the runway number. Most other intersection designations consist of five-letter combinations chosen for their mnemonic value, since either air traffic control or the flight plan may require the pilot to recall the designation.

VNAV - Vertical Navigation

Vertical Navigation in aviation is a function of the autopilot which directs vertical movement of aircraft either according to pre-programmed FMS flight plan during cruise or according to ILS glideslope during approach.

FMS - Flight Management System

is a fundamental part of a modern aircraft in that it controls the navigation. The flight management system (FMS) is the avionics that holds the flight plan, and allows the pilot to modify it as required in flight. The FMS uses various sensors to determine the aircraft's position. Given the position and the flight plan, the FMS guides the aircraft along the flight plan. The FMS is normally controlled through a small screen and a keyboard. The FMS sends the flight plan for display on the EFIS, Navigation Display (ND) or MultiFuction Display (MFD).

EFIS - Electronic Flight Information System

is a flight deck instrument display system in which the display technology used is electronic rather than electromechanical. EFIS normally consists of a primary flight display (PFD), multi-function display (MFD) and Engine Indicating and Crew Alerting System (EICAS) display

GPWS - Ground Proximity Warning System

is a system designed to alert pilots if their aircraft is in immediate danger of flying into the ground or an obstacle.

RNAV - Radio Navigation

Area Navigation (RNAV) is a method of Instrument Flight Rules (IFR) navigation that allows an aircraft to choose any course within a network of navigation beacons, rather than navigating directly to and from the beacons. This can conserve flight distance, reduce congestion, and allow flights into airports without beacons. RNAV can be defined as a method of navigation that permits aircraft operation on any desired course within the coverage of station-referenced navigation signals or within the limits of a self contained system capability, or a combination of these

IFR - Instrument Flight Rules

are regulations and procedures for flying aircraft by referring only to the aircraft instrument panel for navigation. Even if nothing can be seen outside the cockpit windows, an IFR-rated pilot can fly while looking only at the instrument panel. An IFR-rated pilot can also be authorized to fly through clouds, using Air Traffic Control procedures designed to maintain separation from other aircraft.

VFR - Visual Flight Rules

are a set of regulations which allow a pilot to operate an aircraft in weather conditions generally clear enough to allow the pilot to see where the aircraft is going.