• The International Civil Aviation Organisation (ICAO) has prioritised the global deployment of PBN through General Assembly Resolutions (A37-11) and the Global Air Navigation Plan (GANP). 

    States are required to develop implementation plans setting out the adoption of PBN within their airspace structure, including routes and instrument approach procedures.

    Within Europe, the European Commission has developed and published two Implementing Regulations (IR) known as the PCP and PBN IRs.

    Legislative requirements 

  • This mandates the deployment of key ATM Functionalities (AF) or technologies through Implementing Regulation (EU) 716/2014. 

    ATM Functionality (AF#1), describes the deployment of PBN capability, RNP1 with Radius to Fix turns, at major European airports impacting the air traffic management network; for the UK this applies to London Heathrow, London Gatwick, London Stansted and Manchester airports.

    The above airports will be required to comply with the requirement from 1st January 2024 as follows:

    Enhanced Terminal Airspace using RNP-Based Operations consists of the implementation of environmentally friendly procedures for arrival/departure and approach using PBN in high-density TMAs, as specified in the following navigation specifications:

    • SIDs and STARs using the RNP 1 specification with the use of the Radius to Fix (RF) path terminator
    • Required Navigation Performance Approach with Approach Procedure with Vertical guidance (RNP APCH with APV) 

    Enhanced Terminal Airspace using RNP-Based Operations includes

    • RNP 1 SIDs, STARs and transitions (with the use of the Radius to Fix (RF) attachment) 
      RNP APCH (Lateral Navigation/Vertical Navigation (LNAV/VNAV) and Localiser Performance with Vertical guidance (LPV) minima.

    This lays down airspace usage requirements and operating procedures concerning performance-based navigation and describes the wider implications for UK Aerodromes and providers of ATM/ANS over and above the PCP-IR aerodromes. 

    The PBN-IR aims to provide the impetus for all other EASA aerodromes and providers of ATM/AMS to deploy PBN as a safer alternative to non-precision approach procedures, deliver a consistent approach to PBN deployment in en-route, terminal and airport operations whilst ultimately using PBN as sole means of navigation by 2030.

    The U.K. is in the process of opting out of membership of the European Union however, it is expected that European Union adopted legislation will be passed into U.K. law with the existing aims, objectives and timescales.

    It is recognised that other Implementing Regulations and regulatory requirements will influence the development and deployment of these regulations, such as:

    ICAO

    • RNP charting in accordance with ICAO Circular 353; to be implemented in 2020

    EU regulations

    • Commission Regulation (EU) No 73/2010 - Aeronautical Data Quality (ADQ) & amending regulation 1029/2014
    • Commission Implementing Regulation (EU) 2017/373 - Common requirements for providers of air traffic management/air navigation services 

    Business as usual tasks

    • Instrument Flight Procedure 5-year review 
    • Adjustment to the length of SIDs and STARs
    • DVOR rationalisation and removal of dependencies (en-route and aerodromes)

  • PBN-IR requirements 

    The PBN-IR lays down requirements on providers of ATM/ANS including aerodromes.  Only those aerodromes that are certified in accordance with Commission Regulation (EU) No 139/2014 (commonly referred to as EASA aerodromes) are in scope.

  • EASA Aerodromes must comply with the following requirement by 3 December 2020

    Instrument runway ends currently served by only non-precision approach procedures will as a priority and in accordance with Part-AUR.PBN.2005 (1), require '3D approaches' at all Instrument Runway Ends (IREs) through deployment of LNAV, LNAV/VNAV and LPV lines of minima and Radius to Fix (RF) where required.


    EASA Aerodromes must comply with the following requirement by 25 January 2024

    Runway ends served by precision approach procedures will, in accordance with Part-AUR.PBN.2005 (1) deploy '3D approaches' at all Instrument Runway Ends (IREs) through deployment of LNAV, LNAV/VNAV and LPV lines of minima and Radius to Fix (RF) where required.

    Contingency measures shall be provided for non-PBN equipped aircraft during the transition period in the event of loss of GNSS. 


    EASA Aerodromes must comply with the following requirement by 25 January 2024

    Where SID or STARs have been established, at least one RNAV 1 SID or STAR to be implemented, in accordance with Part-AUR.PBN.2005 (4), at all instrument runway ends.  Where a higher performance is necessary on SIDs and STARs the RNP1 specification with vertical constraints and Radius to Fix can be used in accordance with Part-AUR.PBN.2005 (5). 


    EASA Aerodromes must comply with the following requirement by 6 of June 2030

    All remaining SIDs and STARS will utilise the RNAV 1 or RNP1 specification with vertical constraints and Radius to Fix, in accordance with Part-AUR.PBN.2005 (4) and (5). 


    Derogations are applicable as follows

    Where terrain, obstacles or ATS separation require that a 3D approach is not possible a 2D RNP APCH will be implemented along with an RNP AR 3D approach in accordance with Part-AUR.PBN.2005 (2).

    Where suitable SBAS coverage is not available LNAV and LNAV/VNAV will be provided.  LPV will be implemented no later that 18months after SBAS coverage becomes available in accordance with Part-AUR-PBN.2005 (3). 

    This PBN IR chart shows terminal airspace requirements for performance based navigation.

    This requirement must be met by 3 December 2020

    ATS routes FL150 and above shall utilise the RNAV 5 specification in accordance with Part-AUR.PBN.2005 (6). 


    This requirement must be met by 25 January 2024

    ATS routes below FL150 shall utilise the RNAV 5 specification in accordance with Part-AUR.PBN.2005 (6). 


    This requirement must be met by the 25 January 2024

    ATS Routes, SIDs and STARs established for rotorcraft operations shall utilise one of RNP 0.3, RNAV 1 or RNP 1 specification in accordance with Part-AUR.PBN.2005 (7). 


    Providers of ATM/ANS must meet this requirement by 6 June 2030 

    Providers of ATM/ANS shall not provide services using conventional navigation procedures other than for contingency purposes or using a landing system enabling CAT II, CAT IIIA or CAT IIIB operations.

  • UK exceptions to the PBN-IR

    For operational efficiency, performance and economic reasons, the UK has elected to apply exceptions to the PBN-IR in respect of the application of ICAO navigation specifications.

    The UK airspace concept as envisaged under the Airspace Modernisation Strategy (AMS) does not align precisely with that portrayed by the European Commission, for the reasons set out below.

  • UK ATS routes may, where traffic demands exist, apply RNAV 1 and the commensurate route spacing associated with this performance specification. 

    This exceeds the RNAV 5 mandate within Part-AUR.PBN.2005 (6) and the CAA recognises that to revert to an exclusive RNAV 5 ATS route structure would be detrimental to capacity and therefore, the UK's ability to meet obligations and objectives under the Performance Scheme.

    STARs

    UK STARs were originally conceived as conventional arrival routes terminating at a Holding Fix as part of an orbital stack.  The 'stacks' extend across intermediate Flight Levels and in certain instances the characteristic of the STAR is more akin to an en-route ATS segment than a terminal airspace procedure.  A number of UK STARs have therefore been implemented using RNAV 5 in accordance with design guidance published by EUROCONTROL in 2002.

    Either on an opportunity basis e.g., the introduction of a new airspace design or co-incident with the next Instrument Flight Procedure (IFP) review, those STARs currently promulgated using the RNAV 5 specification, will be re-designed using the RNAV 1 specification in compliance with Part-AUR.PBN.2005 (4).

    Note: where the STAR portion of an arrival route extends across intermediate Flight Levels, it is the responsibility of the ANSP managing this airspace to ensure compliance with the requirements of Part-AUR.PBN.2005 (5). 

    The term 'transition' is not recognised by ICAO even though it is a construct that is used commonly on both departures and arrivals and is accommodated within ARINC 424.  A Transition essentially provides a systematic means to link from one route segment to another i.e., from a SID to an ATS route structure or from a STAR to a runway or specific approach procedure.

    Approach Transitions may be applied if the STAR does not terminate at the start of approach.  In the UK all STARs terminate at the Holding Fix and the airspace designer then requires a mechanism to provide connectivity to the runway, either through use of a tactical service or some form of Transition or Initial Approach Procedure.

    The PBN-IR is rather simplistic in construction and only considered the airspace design concept where there is a STAR and then an RNP APCH or RNP AR APCH.  In reality, Transitions are an extension of the arrival procedure, providing aircraft with route connectivity to either the Intermediate Fix or Final Approach Segment.  The navigation data base cannot accommodate a STAR followed by a STAR, hence the requirement for an Approach Transition.

    There is no requirement within the PBN-IR for the provider of ATM/ANS to include Approach Transitions.  However, the CAA would expect the sponsor of the airspace change to consider the Transition as a PBN procedure applying a suitable terminal airspace navigation specification appropriate for the intended performance and functional requirements for that airspace.  Therefore, following an RNAV 1 STAR, the Approach Transition would be expected to be at least RNAV 1 and possibly RNP 1 (with RF) or even Advanced-RNP.  The Transition would then direct traffic into either an xLS (ILS or GLS) procedure, RNP APCH or RNP AR APCH procedure.

    Part-AUR.PBN.2005 (1) requires the provider of ATM/ANS to implement, at all Instrument Runway Ends (IREs), RNP APCH with three lines of minima, namely LNAV, LNAV/VNAV and LPV.  Requiring the three lines of minima provides access to aircraft with both Barometric-VNAV approach and SBAS approach capabilities.  However, at certain aerodromes the airspace user community is SBAS approach capable only, either for reasons of the type of aircraft utilising the aerodrome and/or their navigation equipage.

    The CAA recognises that to insist on those aerodromes implementing an LNAV/VNAV line of minima on an RNP APCH procedure where there is no base-operator willing to support validation of the procedure and no expected use of the procedure, is uneconomic.  To implement and then maintain a service that is unlikely ever to be used is not cost effective and the CAA is prepared to listen to arguments from the sponsor as to why the CAA should support an exception to Part-AUR.PBN.2005 (1).

    Sponsors should include a detailed justification with their PBN Transition Plan for not implementing an LNAV/VNAV line of minima at any IRE, including an analysis of current and expected aircraft user types for the RNP APCH and their navigation equipment capability and any other mitigating circumstances such as Category of Approaches offered and available runway length.

  • Transition and deployment plans 

    Providers of ATM/ANS must establish transition plans 

    This requirement must be met by the 3 December 2020

    Plans must be co-ordinated with airspace users, aerodrome operators, adjacent airspace blocks, Network Manager

    The NSA approval will be conducted by Airspace Regulation, Safety and Airspace Regulation Group, CAA.

    A transition plan constitutes an intent to deploy PBN procedures; approval of the transition plan by the NSA does not constitute agreement to deploy, the airspace change process is described in CAP1616 and will be subject to approval before deployment.

    The individual aerodrome ATM/ANS Transition plan will form the basis of a UK State view of PBN deployment to inform reporting and resource planning as well the ability to monitor deployments to meet the PBN-IR Requirements.

    To help achieve this a planning template has been created as a form to submit to the CAA describing the strategic intent as well as the ambition for procedures to all runway ends.  The form requires a submission per procedure per runway end to ensure as much information is captured without being overly onerous to complete and focuses on the future ambition, not what is currently in place and currently recorded in the Aeronautical Information Publication (AIP).

    The CAA requests that aerodromes provide as much information as is currently available.

    Aerodromes will be able to resubmit the form with updated information, as plans change.

    For the ATS routes and terminal airspace procedures extending across intermediate Flight Levels, including STARs and holds, the CAA will expect a dedicated plan from the provider of ATM/ANS.

    In terms of coordination with the Network Manager (NM), the CAA has submitted a State Report on behalf of UK providers of ATM/ANS, including aerodromes (link to UK PBN Transition Plan).  

    This report reflects the current status of PBN implementation in the UK and CAA expectations for the 2020, 2024 and 2030 compliance dates.  NM has provided feedback to this State Report (link to NM Feedback on PBN Transition Plan) and no further follow-up with NM is required. 

    Notwithstanding this report, providers of ATM/ANS, including aerodromes are still expected to have their individual PBN Transition Plans agreed with the CAA by 03 December 2020.

    Transition planning form

  • Related Information

    The ICAO PBN Manual (ICAO Doc 9613 Edition 4) consists of two volumes:

    Volume I

    • Part A describes the PBN Concept, its role within the airspace concept and how the PBN Concept is used in practice;
    • Part B provides Implementation Guidance for ANSPs in the form of the processes, phases and steps;
      Attachments describe RNAV and RNP systems, data processes and an outline of the operational approval process. 

    Volume II

    • Part A provides a general introduction to the navigation specifications, including specific guidance on on-board performance monitoring and alerting, safety assessments and navigation service monitoring;

    • Part B contains the RNAV navigation specifications, to be used by States as a basis for certification and operational approval;

    • Part C contains the RNP navigation specifications to be used by States as a basis for certification and operational approval;

    • Attachments describe Barometric VNAV and provide sample airspace concepts based on navigation specifications.

    ICAO Manual on the use of Performance-based Navigation (PBN) in Airspace Design (ICAO Doc 9992 Edition 1)
    Performance-based Navigation (PBN) Operational Approval Manual (ICAO Doc 9997 Edition 2).