Definition
A high-precision category of RNP instrument approach procedure that requires special aircraft equipment, specific aircrew training, and explicit operational authorization from the FAA before it may be flown. RNP AR procedures use lateral accuracy values as low as 0.10 NM on final and 1.00 NM on missed approach, may include radius-to-fix (RF) curved path segments, and are designed for use in terrain-challenged or obstacle-rich environments where conventional approaches are not feasible.
Plain English
A very precise GPS-based approach that an operator and crew must be specifically approved to fly. The aircraft must have the right equipment, the pilots must have the right training, and the operation must hold a written authorization from the FAA.
Context Anchor
Seen on certain instrument approach procedures and other published instrument procedures, especially where precise routing is needed because of terrain, obstacles, or busy airspace.
Derivation
Authorization Required' is the literal explanation: unlike standard RNP approaches, no operator may fly these without case-by-case FAA approval. The 'AR' label is a flag on the chart that says 'do not attempt unless specifically cleared to.'
Why Pilots Care
It permits safe approaches into airports surrounded by challenging terrain where conventional procedures would be impossible, provided the operator meets the strict authorization requirements.
Intuition Check
Do not read RNP AR as simply “an RNP procedure.” The “AR” part means special authorization is required before you may fly it.
Example Sentence 1
Our company is approved for RNP AR approaches, so we can use the curved path into the valley airport when other operators have to divert.
Example Sentence 2
Only aircraft certified for RNP AR with specially trained pilots may fly the procedure published for this runway.