special aircraft and aircrew authorization similar to category II/III ILS operations. All RNP AR approaches have reduced lateral obstacle evaluation areas and vertical obstacle clearance surfaces predicated on the aircraft and aircrew performance requirements. The following characteristics differ from RNP APCH: RF leg segments may be used after PFAF (precise final approach fix). lateral TSE values as low as 0.10 NM on any segment of the approach procedure (initial, intermediate, final or missed). When conducting an RNP AR approach using a line of minima less than RNP 0.3, no single-point-of-failure can cause the loss of guidance compliant with the RNP value associated with the approach. Typically, the aircraft must have at least dual GNSS sensors, dual flight management systems, dual air data systems, dual autopilots, and a single inertial reference unit. When conducting an RNP AR approach with a missed approach less than RNP 1.0, no single-point-of-failure can cause the loss of guidance compliant with the RNP value associated with a missed approach procedure. Typically, the aircraft must have at least dual GNSS sensors, dual flight management systems, dual air data systems, dual autopilots, and a single inertial reference unit. Flight planning Manual or automated notification of an aircraft's qualification to operate along an air traffic services (ATS) route, on a procedure or in an airspace is provided to ATC via the flight plan. See also Acronyms and abbreviations in avionics Notes References Further reading Air traffic control