Final answer:
RNAV is a navigation system that uses RNP to define aircraft accuracy. It allows pilots to follow predefined flight paths using on-board systems like GPS.
Step-by-step explanation:
RNAV stands for Required Navigation Performance, which is a type of navigation system used in aviation. It relies on RNP or Required Navigation Performance to define a specific level of accuracy for the aircraft's navigation. With RNAV, pilots can follow predefined flight paths without relying solely on ground-based navigation aids.
For example, a specific flight may require an RNP of 0.3, which means that the aircraft must be able to navigate within a radius of 0.3 nautical miles of its intended track. RNAV uses a combination of on-board systems, including GPS, to ensure accurate navigation.