Definition
An area navigation specification requiring the aircraft's lateral navigation system to maintain a total system error of no more than 2 nautical miles for at least 95 percent of the flight time. RNAV 2 applies primarily to en route operations in the continental United States, including Q-routes and T-routes, and to certain RNAV departure and arrival procedures.
Plain English
A navigation standard that says the aircraft must stay within 2 nautical miles of the intended track at least 95 percent of the time. The '2' is the allowed accuracy in nautical miles.
Context Anchor
Seen on RNAV departure, arrival, and route requirements when checking whether the aircraft and crew are allowed to fly that procedure.
Derivation
RNAV stands for area navigation, meaning the aircraft can fly any chosen path rather than only point-to-point between ground-based navaids. The number after RNAV is the lateral accuracy required, in nautical miles.
Why Pilots Care
It enables more direct routes and access to procedures that require this level of navigation performance.
Intuition Check
RNAV 2 does not mean “version 2” of RNAV. The number tells you the required navigation accuracy: within 2 nautical miles of the intended path.
Example Sentence 1
The departure procedure required RNAV 2, so the crew confirmed the FMS was tracking within tolerance before accepting the clearance.
Example Sentence 2
RNAV 2 routes let controllers assign more efficient paths through busy airspace.