RNP Monitoring and Alerting
One of the many features of NZ FMS 6.1 is Required Navigational Performance (RNP) monitoring and alerting. RNP enables many procedures to be used that would not otherwise be available. RNP provides the statistical level of position accuracy and integrity of area navigation (RNAV) along with onboard monitoring and alerting, as described below. The RNP functionality included with the NZ FMS 6.1 upgrade meets the ICAO requirement for RNP approaches.
RNP-based instrument procedures have been expanding to airports around the globe. RNP-based procedures now encompass Standard Instrument Departures (SIDs), Standard Terminal Arrival Routes (STARs), and approaches. RNP is also used enroute (e.g. oceanic RNP-4).
RNP procedures that require the ICAO Performance-Based Navigation (PBN) standard are appearing internationally. These procedures require the RNP onboard-monitoring and alerting features offered with the NZ FMS 6.1 upgrade. Procedures requiring RNP monitoring and alerting capabilities (SIDs, STARs, and approaches) will show such requirements in the notes of the respective chart.
The specification depicts RNP1 to call out the RNP monitoring and alerting requirement for SIDS and STARS.
RNAV Departure Requiring RNP
When the primary navigation source is from the FMS, an FMS lateral deviation and RNP value is displayed on the Primary Flight Display (PFD) in the same location as the rate-of-turn display. When in map mode, the RNP is displayed.
Honeywell FMS 6.1 RNP Graphical Display Example
The graphical display shows a center magenta triangle with winglets on either side, allowing the pilot to quickly determine the system’s current accuracy. The triangle represents the lateral deviation from the course centerline, while the horizontal line on each side represents the EPU error. The winglets on each end represent the total system error (as defined above). If there is a loss of RNP integrity, the display changes to amber.
RNP monitoring and alerting capability are becoming invaluable for pilots as these types of procedures continue to expand throughout the world.
For more information on RNP, please see Honeywell’s June Newsletter article, “RNAV and RNP Navigation Specifications – Keeping It All Straight.”
Please contact Honeywell Flight Technical Services with any questions or operational issues.