Definition
The set of published Required Navigation Performance (RNP) values that define the lateral navigation accuracy an aircraft must maintain for a given phase of flight. Each level is expressed in nautical miles and represents the distance, left or right of the intended track, within which the aircraft must remain for at least 95 percent of the flight time. Common standard levels include RNP 10 and RNP 4 for oceanic and remote operations, RNP 2 and RNP 1 for en route and terminal operations, and RNP 0.3 or lower for approach operations.
Plain English
These are the official accuracy standards that tell a pilot how tightly the aircraft must stay on its planned track. The smaller the number, the tighter the required accuracy. A different level applies to each phase of flight, from ocean crossings down to final approach.
Context Anchor
Seen in RNAV and RNP instrument procedure discussions, especially when a chart or procedure states the navigation performance needed to fly that route or segment.
Derivation
Required Navigation Performance describes exactly what the phrase says: the navigation performance required for an operation. In this term, “level” means the set numeric requirement, not a training stage or difficulty rating.
Why Pilots Care
Pilots must confirm their aircraft meets the published RNP level before flying a procedure, or they cannot legally or safely use it.
Intuition Check
Do not read “level” as a general skill level or a rough category. In Standard RNP Levels, the level is a specific number in nautical miles, and a smaller number means a tighter navigation requirement.
Example Sentence 1
The oceanic track required RNP 4, so the crew confirmed the aircraft was authorized for that level before departure.
Example Sentence 2
Most enroute segments allow Standard RNP Levels of 2.0, which is less demanding than the tighter values used on final approach.