The aircraft requirements for RNAV 1 and 2 are identical, while some operating procedures are different. The RNAV 1 and 2 navigation specification is applicable to all ATS routes, including routes in the en‐route domain, standard instrument departures (SIDs), and standard arrival routes (STARS). It also applies to instrument approach procedures up to the final approach fix.
The RNAV 1 and 2 navigation specification is primarily developed for RNAV operations in a radar environment (for SIDs, radar coverage is expected prior to the first RNAV course change). The Basic‐ RNP 1 navigation specification is intended for similar operations outside radar coverage. However, RNAV 1 and RNAV 2 may be used in a non‐radar environment or below Minimum Vectoring Altitude (MVA) if the implementing state ensures appropriate system safety and accounts for lack of performance monitoring and alerting.
For RNAV 1 and RNAV 2, the following navigation criteria are defined: GNSS, DME/DME and DME/DME/IRU. Where DME is the only navigation service used for position updates, gaps in DME coverage can prevent position update. Integration of inertial reference units (IRUs) can permit extended gaps in coverage.
RNAV 1 and RNAV 2 routes are envisioned to be conducted in direct controller‐pilot communication environments.
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