Definition
A network of published air routes that uses area navigation (RNAV) rather than ground-based navigation aids. RNAV allows aircraft to fly directly between any two defined points in space, so these routes are not tied to the location of VORs, NDBs, or other physical navaids. The system includes high-altitude Q-routes (used in the jet route structure above 18,000 feet MSL) and low-altitude T-routes (used below 18,000 feet MSL).
Plain English
A set of official flight routes that aircraft follow using onboard navigation equipment instead of flying from one ground station to the next. Because the routes don't depend on ground transmitters, they can be drawn as straight lines between useful points, making flights more direct.
Context Anchor
Seen on instrument en route charts and in air traffic control clearances, especially when a route is based on area navigation instead of older ground-station airways.
Derivation
RNAV stands for area navigation. The 'area' part is the key idea: instead of being forced to fly from one navaid to another, the aircraft can navigate within an area defined by waypoint coordinates. The term distinguishes this approach from traditional point-to-point navigation along ground-based airways.
Why Pilots Care
Supports more direct routing, lower fuel burn, and access to performance-based navigation airspace.
Intuition Check
Do not read “RNAV route system” as “go anywhere you want.” It means published, charted routes made for aircraft that can legally and accurately use area navigation.
Example Sentence 1
The crew filed a flight plan along the RNAV route system, using Q-146 to take advantage of a more direct path at FL340.
Example Sentence 2
Aircraft equipped with GPS commonly follow the RNAV route system for enroute segments.