RNAV

Area Navigation (RNAV) is a method of air 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 instrument flight plans into airports without beacons.
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A method of using navigation instruments that allows pilots flexibility to fly direct routes between waypoints or offset from published or established routes/airways at specified distance and direction. (FAA6)

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. Random area navigation routes are direct routes, based on area navigation capability, between waypoints defined in terms of latitude/longitude coordinates, degree/distance fixes, or offsets from published or established routes/airways at a specified distance and direction. The major types of equipment are: 1) Combined VOR and TACAN navigational facility (VORTAC) referenced or Course Line Computer (CLC) systems, which account for the greatest number of Radio Navigation (RNAV) units in use. To function, the CLC must be within the service range of a VORTAC. 2) OMEGA/VLF, Although two separate systems, can be considered as one operationally. A long-range navigation system based upon Very Low Frequency (VLF) radio signals transmitted from a total of 17 stations worldwide. 3) Inertial navigation systems (INS), which are totally self-contained and require no information from external references. They provide aircraft position and navigation information in response to signals resulting from inertial effects on components within the system. 4) Microwave Landing System (MLS) Area Navigation (MLS/RNAV), which provides area navigation with reference to an MLS ground facility. 5) LORAN-C is a long-range radio navigation system that uses ground waves transmitted at low frequency to provide user position information at ranges of up to 600 to 1,200 nautical miles at both en route and approach altitudes. The usable signal coverage areas are determined by the signal-to-noise ratio, the envelope-to-cycle difference, and the geometric relationship between the positions of the user and the transmitting stations. (FAA4)

Area Navigation
  

(See AREA NAVIGATION.)
(See ICAO Term AREA NAVIGATION.)