Part 4: PBN – RNP APCH, RNP AR APCH, RNP AR DP and A-RNP

Part 3: PBN – Airspace Concept

RNP Approach (RNP APCH)

RNP Approach procedures are titled as RNAV(GPS) and offer several level of minima to accommodate varying aircraft equipage:

LNAV
LNAV/VNAV
Localizer Performance with Vertical Guidance (LPV)

More information on LNAV, LNAV/VNAV and LPV is given in consecutive parts.

Key points of RNP Approach:

RNP APCH has lateral accuracy value of 1 in terminal and missed approach segment and 0.3 RNP in final approach
Vertical guidance in LNAV/VNAV can either be barometric or SBAS vertical
SBAS is mandatory for only LPV or LP minima

RNP AR APCH and RNP AR DP (Authorization Required Approach and Departure)

RNP AR APCH and RNP AR DP stands for RNP Authorization Required Approach and Departure respectively. These approaches/departures procedures are titled as RNAV (RNP) in charts. (Note: RNP Approach are titled as RNAV(GPS))

RNP AR APCH id defined as RNP appraoch procedure that requires a lateral TSE (Total Sysem Error) lower than standard RNP values in any segment of approach procedure.

Both RNP AR APCH and DP have stringent equipage and pilot training standards and also require special authorization to fly. Scalability and RF(radius to fix turn) capabilities are mandatory in RNP AR APCH and RNP AR DP. These procedures are designed to specific benefits at specific locations.

Key points on RNP AR APCH and RNP AR DP:

more stringent equipage and pilot training standards required
needs special authorization to fly
intended to provide specific benefits at specific locations
not designed for all operators
required specific aircraft performance, design, operational processes, training to achieve target level of safety
lateral accuracy values can range below 1 in terminal and missed approach segments and scale to RNP 0.3 or lower in final approach

Advance RNP (A-RNP)

Advance RNP is navigation specification with certain minimum set of mandatory functions enable in aircraft’s avionics system. For example: these minimum functionalities in US include capability to calculate and perform RF turns, scalable RNP, and parallel offset flight path generation.

Sometimes there may be demand of dual systems or more redundancy on oceanic or remote continental airspace. Use of A-RNP is generally associated with use of autopilot and/or flight directors. A-RNP eligible are NOT automatically eligible for RNP AR APCH or RNP AR DP but is eligible for RNP/RNAV 1, RNP/RNAV 2, RNP 4, and or RNP/RNAV 10. Advance RNP allows for scalable RNP lateral navigation values (either 1.0 or 0.3) in terminal environment

IMPORTANT : Word “RNP” is associated with lateral accuracy level, NO specific vertical minima value has been associated with RNP APCH and RNP AR APCH.