PBN Requirements for Route Segment

Owned by Wolfgang Scheucher
Last updated: 2021 Oct 13
Page Table of Content

Introduction

For Route Segment, PANS-AIM requires as part of the minimum data set information about the navigation specification and required navigation performance.

For the AIP data set PANS-AIM requires 2 properties related to Performance Based Navigation (PBN) of a route segment.

  • "Navigation specification"

Designation of the navigation specification(s) applicable to a specified segment(s) -  There are two kinds of navigation specifications:

Required navigation performance (RNP) specification. A navigation specification based on area navigation that includes the requirement for performance monitoring and alerting, designated by the prefix RNP, e.g. RNP 4, RNP APCH.

Area navigation (RNAV) specification. A navigation specification based on area navigation that does not include the requirement for performance monitoring and alerting, designated by the prefix RNAV, e.g. RNAV 5, RNAV 1.

  • "PBN requirements"

Area navigation based on performance requirements for aircraft operating along an ATS route, on an instrument approach procedure or in a designated airspace requirements
This property is split into 2 sub-properties

    • "Navigation performance requirements"

The navigation accuracy requirement for each PBN (RNAV or RNP) route segment

    • "Sensor requirements"

Indication on the sensor requirements including any navigation specification limitations

ICAO Doc 9613 (PBN Manual)  describes the following designation of Navigation Specifications:

The following table shows the Application of navigation specification by flight phase:

The diagram below shows the AIXM 5.1(.1) classes, including the relevant data types, that may be used to encode that information:

AIXM 5.1.1 issue 005_RouteSegment.navigationType

AIXM 5.1.1 provides two attributes regarding navigation specifications for a RouteSegment. Both seem to be insufficient to code the designation of the PBN specification.

  • navigationType is basically used to encode if the route is 'CONV 'or 'RNAV', but is not intended to code the PBN specification (such as RNAV 5 , RNP 4 etc.).  'OTHER' could be used to define the missing value for PBN Navigation Specification, i.e. 'OTHER:RNP'.
  • requiredNavigationPerformance is intended to code RNP values (any two-digit value with one decimal is allowed).

This has been raised as an issue to the AIXM CCB to be considered for AIXM 5.2. For the status of the Change Proposal see AIXM-135

Proposed Workaround for AIXM5.1(.1):

Code for navigationType 'RNAV' or 'OTHER:RNP'

and for requiredNavigationPerformance the navigation acurracy, e.g. '5' or '4'.

The two concatenated values would result in the corresponding RNAV or RNP navigation specification, e.g. RNAV 10 or RNP 4, according to the values defined in ICAO Doc 9613 (PBN Manual).

Note: This workaround does not work for one PBN navigation specifications applied for en-route: The Advanced RNP (A-RNP). For this particular case an corresponding Note may be provided.

AIP context

In an AIP this information is published in the ENR 3 section.

Coding Examples

Coding examples can be found in the AIP Data Set - Specimen (DONLON).

No.DescriptionXPath Expression
RSG-EX-01Route segment with navigation specification

//aixm:RouteSegmentTimeSlice[@gml:id ='RSG_UA4_BARIM_WOB']

References