Definition
A type of performance-based navigation (PBN) that specifies a required level of navigation accuracy, expressed in nautical miles, that an aircraft must maintain along a route, procedure, or in a defined airspace, and which includes onboard performance monitoring and alerting. The aircraft's navigation system must continuously verify it is meeting the required accuracy and warn the crew if it is not.
Plain English
A standard that says how accurately an aircraft must be able to navigate on a given route or procedure, with the aircraft itself checking its own accuracy and telling the pilot if it falls short.
Context Anchor
Pilots encounter Required Navigation Performance on instrument procedures, arrival and departure routes, chart notes, and aircraft approval documents.
Derivation
The phrase is built from three plain words. "Required" means it must be met, not optional. "Navigation" means knowing where you are and where you're going. "Performance" here means how well the aircraft's navigation system actually does its job — its accuracy in practice, not just on paper. Together: a stated accuracy level the aircraft is required to deliver and confirm.
Why Pilots Care
It determines whether an aircraft is permitted to fly precise routes or approaches that save time, reduce fuel use, and provide access to airports with limited ground navigation aids.
Analogy
Think of the planned route as a narrow hallway in the sky. Required Navigation Performance says how narrow that hallway is and requires the navigation system to alert you if it can no longer keep you reliably inside it.
Intuition Check
Do not read performance here as a general judgment of how well the pilot flies. In this FAA use, it means a specific navigation capability the aircraft must meet, including a warning if that capability is lost.
Example Sentence 1
The approach required an RNP value of 0.3, meaning the aircraft had to stay within three-tenths of a nautical mile of the centerline and confirm that accuracy throughout the procedure.
Example Sentence 2
The en route chart noted Required Navigation Performance 2.0 for the direct routing through the busy terminal airspace.