Plain English Meaning
A rule that says how accurately the aircraft must be able to follow its intended track, plus a requirement that the aircraft itself can warn the pilot if it loses that accuracy.
Full Definition
A statement of the navigation accuracy needed for an aircraft to operate within a defined airspace, route, or procedure, expressed as a number that represents the lateral distance in nautical miles within which the aircraft must remain at least 95 percent of the flight time. RNP also requires that the aircraft's navigation system be capable of monitoring its own performance and alerting the crew if that accuracy cannot be met.
Context Anchor
Seen on RNAV and RNP instrument approach charts, requirements, and before flying an .