Definition
RNAV routes are published air traffic service routes flown using area navigation, which allows an aircraft to fly any desired path between waypoints rather than being restricted to navigating directly to or from ground-based navigation stations. On IFR en route low altitude charts, RNAV routes are typically depicted in blue and labeled with a 'T' prefix for low altitude RNAV routes (T-routes) or a 'Q' prefix for high altitude RNAV routes (Q-routes), with defined waypoints, mileages, and minimum altitudes.
Plain English
These are pre-published flight paths in the sky that you fly using GPS or another area navigation system, instead of having to fly from one ground radio station to the next. The route is made up of named waypoints, and you fly directly between them.
Context Anchor
Seen on en route charts used for instrument flight, especially on low altitude charts where RNAV routes may appear as charted paths between named points.
Derivation
RNAV stands for Area Navigation. The 'area' part is the key idea: instead of being tied to flying along a line drawn from one ground station to another, you can navigate freely within an area, as long as your equipment can tell you where you are.
Why Pilots Care
They permit more direct routing, reduce flight time and fuel use, and support efficient IFR operations in busy or complex airspace.
Intuition Check
RNAV routes are not just any GPS course a pilot chooses. They are published instrument routes with specific charted paths and equipment requirements.
Example Sentence 1
We filed T-295 from PXT to ENO, which kept us on a published RNAV route at 5,000 feet.
Example Sentence 2
On the en route chart the controller assigned an RNAV route that cut across several traditional airways.