Consideration of further work in WG IPS on issues raised at the APANPIRG CNS/MET SG/11 meeting

- 2 -

ACP-WGI/02/WP-08

- 3 -

ACP-WGI/02/WP-08

International Civil Aviation Organization

WORKING PAPER

ACP-WGI/02/WP-08

22 August 2007

AERONAUTICAL COMMUNICATIONS PANEL (ACP)

SECOND MEETING OF WORKING GROUP I

INTERNET PROTOCOL SUITE

Montreal, Canada 27 – 31 August 2007

Agenda Item xx:

Consideration of further work in WG IPS on issues raised at the APANPIRG CNS/MET SG/11 meeting

TITLE

(Presented by the Secretary)

SUMMARY

This paper presents the result of the eleventh meeting of the CNS/MET subgroup

ACTION

The meeting is invited to develop any material necessary for global implementation of ATN/IPS

1. INTRODUCTION

1.1 The eleventh meeting of the CNS/MET subgroup of the APANPIRG was held from 16-20 July 2007 in Bangkok, Thailand. This meeting reviewed various issues relating to the use of IPS, including ATSMHS over IPS. The report of this meeting on agenda item 3 and 4 (Aeronautical Fixed Service and Aeronautical Mobile Service) is attached.

2. discussion

2.1 A large part of the report is dedicated to ATSMHS implementation activities in the ASIA/PAC Region. It was noted that in the CAR/SAM Region, ATSMHS implementation is taking place using IPv4, recommending interregional only using IPv6. This matter may need further clarification from the CAR/SAM Region, as well as further consideration in WG IPS, in particular with the view to develop implementation and/or transition strategies for IPv6 in the longer term.

2.2 The CNS/MET subgroup also noted the limited availability of ATSMHS products capable to support IPv6. ATSMHS can be implemented over TCP/IP through RFC 1006. WG IPS should provide further guidance on this matter.

2.3 AMHS can support BUFR Coded meteorological messages through a File Transfer Body Part (FBTP) solution. This would need some further clarification, in particular for networks using TCP/IP (either IPv4 or IPv6). It was noted that another ET in WMO was being established to develop guidance for the use of XML. It was understood that the regional BUFR transition would be frozen until the result of discussion of new ET are known and new directive from Air Navigation Commission is available.

2.4 The CNS/MET subgroup considered the AMHS address registration and the need for an ATSMHS Messaging Management Centre (AMC). The need and role of this AMC would need further clarification, in particular since an AMHS data base is already available through ICAO (ACP website).

2.5 An ATN/AMHS Seminar workshop is planned for early 2008. The role of this Seminar, in particular with regard to the ongoing work in ACP on ATN/OSI SARPs and guidance material should be further assessed. In particular it may be useful to bring to this Seminar the results of ongoing work on ATN/IPS and its compatibility with AFTN, IPv4 implementations, ATN/OSI implementations and AMHS.

2.6 The CNS/MET subgroup noted that the interregional connection between Chile and New Zealand is actually implemented via the USA. Also, the USA is implementing, using the RFC-1006 Gateway, converging TCP/IP and OSI. These implementations may need some further study in WG IPS, with the view to develop relevant guidance material

2.7 With regard to the air-ground data link implementation, the sub-group was addressing FANS 1/A implementations. In this regard it should be noted that RTCA has developed, through SC 186, material describing FANS 1/A interoperability with the ATN (most likely ATN/OSI). WG IPS is invited to provide further guidance on this development.

3. ACTION BY THE MEETING

3.1 ACP Working Group I is invited to consider the various elements on the report of the CNS/MET subgroup meeting of APANPIRG with the view to develop guidance material, as necessary, facilitating global implementation of ATN/IPS.

Appendix: report of the APANPIRG CNS/MET SG/11 meeting on agenda items 3 and 4

Agenda Item 3:Aeronautical Fixed Service:

1) review Report of the Second Meeting of the ATN Implementation

Coordination Group (ATNICG/2)

2) review report of AIDC Review Task Force and AIDC Plan

3) discuss other AFS related issues

Review Report of the Second Meeting of the ATN Implementation Coordination Group (ATNICG/2)

3.1The Second ATNICG Meeting was hosted by Hong Kong, China from 28 May to 1 June 2007 and was attended by 75 participants from 18 States, ARINC, SITA and 8 Industries. The meeting considered 25 Information Papers and 23 Working Papers and formulated 2 Decisions, 1 draft Decision and 3 draft Conclusions.

3.2 The meeting reviewed the TOR of ATNICG and did not consider the need for change. The meeting reviewed the Subject/Tasks List updated by ATNICG/2 based on the progress made and endorsed the following draft Decision:

Draft Decision 11/3 - Revision to the Terms of Reference and the Subject/Tasks List of ATNICG

That, the Revised Subject/Tasks List of the ATNICG provided in Appendix D to the Report be adopted.

AMHS Implementation in CAR/SAM Regions

3.3The Meeting noted the progresss of AMHS implementation activities in the Caribbean and South America Regions (CAR/SAM). The meeting noted a strategy for implementation of AMHS over TCP/IP utilizing IPv4 to replace their Aeronautical Fixed Telecommunications Network (AFTN) switches. IPv6 was recommended for inter-regional connectivity. During the transition phase, it was proposed to use a dual stack transition mechanism where both IPv4 and IPv6 are implemented in all the Routers and incrementally in AMHS systems.

Use of IPv6

3.4The ATNICG/2 expressed concerns for implementation of IPS using IPv6 in the near term. SARPs for IPS developed by Aeronautical Communication Panel (ACP/1) will become applicable in the end of 2008. There is an on-going task for Working Group N of ACP to develop guidance material for implementation. Additional guidelines on the use of IPS may also need to be further developed for regional implementation. It was noted that AMHS Products capable to support IPv6 were very limited and implementation of IPv6 in the near term was not considered practical in the ASIA/PAC Region.

Cost of Leasing Low Speed Circuit

3.5The meeting noted that more than 100 low speed AFTN circuits are implemented in the CAR/SAM region. The costs of keeping the low speed circuits would be same or even higher than leasing 64 Kbps or higher signaling speed circuits. The same was confirmed in some countries in the ASIA/PAC Region. Therefore, States had been encouraged to upgrade the signaling speed to increase the channel capacity to support ATSMHS. However, it was noted that some AFTN switches used by States were able to support maximum channel speed up to 19.2 Kbps only.

Interregional Connection

3.6The meeting noted that interregional connection between Chile and New Zealand is specified in the AMHS transition plan of the CAR/SAM Region. However, there is no such link that has been planned in the ASIA/PAC FASID Table CNS-1B. The traffic to/from CAR/SAM region from/to ASIA/PAC Region will be via USA. Therefore, requirement of interregional connection with CAR/SAM Region using IPv6 would only be required for consideration by USA and CAR/SAM Region. The Secretariat was requested to contact CAR/SAM region to identify and coordinate the issue of inconsistency in the planning of interregional connection for ATN/AMHS implementation.

Binary Universal Form for the Representation of meteorological data (BUFR)

3.7

The meeting recalled that in accordance with the Working Arrangements between ICAO and WMO (Doc 7475), the codes used for ground-to-ground dissemination and exchange of OPMET information (METAR/SPECI and TAF) lies with WMO and it is therefore not possible for ICAO to choose the code by itself. The BUFR code form is contained in WMO publication No.306, Manual on Codes Volume I. The meeting was informed that the migration plan to aeronautical MET codes which is still valid included enabling use of the BUFR code form on bilateral basis as of November 2007 and full implementation of the BUFR code form in 2016 for all the exchangers of the OPMET data. It was noted that the WMO Commission for Basic Systems (CBS) Expert Team (ET) on data representation and codes recently concluded that only the aviation community could evaluate the capability of its information technology (IT) infrastructure and its own ability to support code changes. The meeting recalled that ATNICG/1 had confirmed AMHS would be able to support the requirements for BUFR coded messages through a File Transfer Body Part (FTBP) solution. It was noted that another ET was being established to develop guidance for the use of XML. It could be expected that the BUFR transition would be frozen until the result of discussion of new ET are known. Agreement by the Air Navigation Commission to this course of action will be sought later in 2007.

First Meeting of Aeronautical Communication Panel (ACP/1)

3.8The meeting noted the outcome of ACP/1 which was held in Montréal, from 10-18 May 2007. The report of the meeting is available on the following ACP website:

http://www.icao.int/anb/panels/acp/wgdoclist.cfm?MeetingID=188

3.9 Some of the outcome effects on ATN/AMHS related issues are as follows: Recommendation (3/1), inviting ICAO to amend Annex 10, Volume III, Part I, Chapters 1 and 3. Draft SARPs that would be introduced in Annex 10 include material based on the internet protocol suite (TCP/IP). Such introduction would need to take place in a manner that already on-going ATN/OSI implementations, both ground-ground and air-ground, would not become obsolete. Technical material for the ATN/IPS would use standards developed by the Internet Society (ISOC) and the Internet Engineering Task Force (IETF).

3.10The meeting noted the ongoing updating of the Manual of Technical Provisions of the ATN and its publication in several parts of the Manual on detailed technical specifications of the ATN/OSI Doc 9880.

3.11 Further work in particular with regard to the air-ground part of the ATN including the future use of CPDLC application over the ATN/IPS was identified. Further work on security of ATN particularly in air-ground data links was identified. It was clarified that use of IPS to support air/ground communication was desirable and feasible. However it is not clear at this stage whether IP can be supported over VDLM2. The meeting noted the other relevant outputs of the ACP/1.

Updates on the Development of Technical Provisions for AIDC

3.12 In following up the outcome of First Meeting of OPLINK Panel, the ACP WGN Meeting held in Bangkok 2007 reviewed and approved updates and amendments to technical provisions for AIDC as contained in the Doc 9705. It was anticipated that the updated material for the AIDC technical provisions will be published in a new ICAO document, Manual on detailed technical specifications of the ATN/OSI (Doc 9880), Part IIA. It was noted that Part I (CM and CPDLC) and Part IIA (AIDC) of Doc 9880 have been approved and have been placed on the ACP website. Updates of the relevant material on ATSMHS and upper layer communications service (ULCS) are in progress and are expected to be published in the near future.

Guidance Document for AMHS Conformance Testing

3.13The meeting reviewed the final draft of AMHS Conformance Document presented by Singapore on behalf of a group of States established by ATNICG consisting of China, Hong Kong China, Indonesia, Singapore, Republic of Korea and United States. ATN/AMHS Conformance document describes requirements to ensure interconnectivity and interoperability. The document was adapted with a baseline from the Eurocontrol Conformance Document. The adaptation of the Eurocontrol Manual focuses on the use of AMHS with additional ATN router testing procedure which was developed based on the router testing and trials conducted between Hong Kong China and Japan. In view of the foregoing, the meeting endorsed the following draft Conclusion:

Draft Conclusion 11/4 - Guidance Document for AMHS Conformance Testing

That, the Guidance Document for AMHS Conformance Testing as provided in Appendix E to the Report be adopted and published as First Edition for use in the Asia and Pacific Region.

ATN/AMHS Implementation Planning Status

3.14 Under this agenda item, the meeting reviewed the ATN/AMHS implementation and planning status presented by Australia, Bangladesh, China, Hong Kong China, Fiji, India, Indonesia, Japan, Republic of Korea, Singapore, Sri Lanka, Thailand and USA.

3.15 The Secretariat demonstrated a web based database on the implementation and planning status in ICAO APAC website where information on focal contact point, planning and implementation status and link data is provided. An implementation forum has also been created in the same ICAO APAC web page. The planning information and implementation status of ATN/AMHS in the Region as mentioned in the previous paragraph including the information received before the meeting from Malaysia, Macau-China and the Philippines were consolidated and reflected in the form of an ATN Connection Chart at the following ICAO APAC web page under the Regional Planning Projects: http://www.icao.or.th/apac_projects/atn_amhs.html

3.16 The meeting reviewed with interest the Chart uploaded with the latest implementation planning information. It was encouraging to see the progress of implementation of ATN/AMHS made by States in the region.

Use of Internet for ATN/AMHS Functional and Interoperability Testing

3.17The meeting noted the experience gained by Hong Kong, China in the use of Internet as an alternative communications means to the public X.25 PSDN, IDD or leased circuits for ATN/AMHS functional and interoperability testing at reduced costs. It was concluded that the public Internet is a flexible means for conducting short-term ATN and AMHS technical trials to verify functionality and interoperability of systems from different equipment manufacturers. Use of the Internet for ATN/AMHS trials also supports multi-partite trials on the message relaying functions and ATN link changeover/re-routing trials that cannot be practically/effectively achieved by using public X.25 PSDN, leased circuits and/or IDD connections. Using public internet for testing was further confirmed and supported by China, Japan, Thailand and USA. Only concern expressed was the security if it is made available for operational use.

Interregional Coordination and AMC Coordination Meeting

3.18The meeting noted that as a follow-up action to the ATNICG WG/1 meeting, an ATS Messaging Co-ordination Meeting was held in Brussels from 27 to 29 March 2007. The main objective of the meeting was to evaluate the capability and functions of the AMC and to analyze the possibilities for the establishment of similar functions in the ASIA/PAC region during the short and the medium terms. Representative from China, Hong Kong-China, Singapore, Thailand and USA visited the ATS Messaging Management Centre at Eurocontrol and attended the coordination meeting. The meeting recognized that common procedures and co-ordination should be formulated globally as a matter of urgency for harmonized implementation, especially when most of the States will implement the ATN infrastructure and AMHS in 2007/2008 timeframe.

ASIA/PAC Interim AMHS Address Management Database

3.19The meeting noted the offer made by Eurocontrol for a global database service to be provided to all ICAO Regions. It was agreed by APANPIRG that the work on the proposed establishment of ASIA/PAC database in Bangkok should progress. The ASIA/PAC database could share data and synchronize data between databases. In following up the directives from APANPIRG, Aerothai has developed an interim AMHS database based on specifications and suggestions from Hong Kong, China and Japan. The database application is provided using web technology.

Using European AMC Database in the short term

3.20Considering that many States in the region plan to implement AMHS by 2008, the AMHS address registration and other related information is needed before the end of 2008. The meeting agreed that, in the short term the AMC database is the only one that can be made available in the Asia/Pacific region. It was recognized that data verification within the region before submission to EUROCONTROL was essential. Data should be submitted by operational staff at the COM centres. Therefore it is logical to have one focal point for consolidation of information within the region.

3.21AEROTHAI was requested to act as an information consolidator for the Asia/Pacific Region and for coordination with EUR region, until the AMHS coordination and management centre (ACMC) in the ASIA/PAC Region is established. AEROTHAI will act as External COM Center for the Asia/Pacific region and relay AMHS information to AMC following the AMC AIRAC updating cycle. This will be the interim arrangement.

3.22In this connection, the meeting noted that in response to the report of AFSG/10 meeting, ICAO Headquarters agreed in principle to the Conclusion 10/11 of AFSG/10, to provide a timely and comprehensive global solution for both formal AMHS address allocation and operational address management. The institutional arrangement is expected to follow the pattern already established for the global management of 5 letter name codes (5LNC), which is based on an agreement between ICAO Headquarters and Eurocontrol.

ATSMHS Coordination and Management Centre

3.23The meeting noted the medium term solution proposed by ATNICG for AMHS address management. Medium-term target is to continue the effort for establishment of a regional AMHS Coordination and Management Centre (ACMC) in the Asia and Pacific Region that can automatically exchange data with the AMC.

ATS Inter-facility Data Communication Plan

3.24

The meeting reviewed the FASID Table for AIDC CNS-1D updated by the second meeting of ATNICG and endorsed the draft Conclusion formulated by the AIDC Review Task Force. The updated FASID Table CNS-1D was further updated and is provided at Appendix F to the Report for consideration by APANPIRG/18. The meeting also noted that the Table would be renamed as FASID Table CNS-1E - ATS Inter-Facility Data Communication (AIDC) Implementation Plan. Accordingly the meeting endorsed the following draft Conclusion.

Draft Conclusion 11/5 - Amendment to FASID Table CNS-1E

That, FASID Table CNS-1E, ATS Inter-facility Data Communication (AIDC) Implementation Plan, be replaced with the updated Table in accordance with the established procedure.

ATN/AMHS Seminar/Workshop

3.25The meeting considered that technical and operational trainings on AMHS are very important for the smooth implementation of ATN/AMHS in the Asia and Pacific Regions. Therefore, in a timely manner a workshop/seminar for the exchange of experiences gained and lesson learned should be conducted. The meeting recalled that the ATN Seminars were hosted by Aerothai once every two years on a regular basis. It is therefore expected that the next one will be in early 2008. Accordingly, the meeting endorsed the following draft Conclusion.

Draft Conclusion 11/6 - ATN/AMHS Implementation Seminar/Workshop

That, ICAO be invited to coordinate with the State concerned to conduct an ATN/AMHS Seminar/Workshop to address implementation issues in early 2008.

Revised ICD for AMHS

3.26The meeting reviewed the revised AMHS Interface Control Document (ICD) to include the use of CAAS addressing scheme and IPM-88. Further more, the opportunity was taken to revise text concerning the network layer of the AMHS protocol stack to clarify sub-networks and the corresponding SNDCF protocols. The meeting agreed with the proposed changes as indicated in Appendix G to the report and formulated the following draft Conclusion.

Draft Conclusion 11/7 - Amendment to AMHS ICD

That, the revised AMHS ICD provided in the Appendix G to the Report be adopted as Edition 2 of ASIA/PAC AMHS ICD.

TCP/IP and OSI Gateway in USA

3.27USA presented an information paper on the national network on convergence over TCP/IP using the RFC 1006 technique. The FAA has developed an RFC-1006 Gateway which resides in their ATN router. The RFC 1006 gateway translates from TCP/IP to OSI and vice versa. The FAA’s implementation architecture will be transparent to a remote MTA and ATN router. The meeting further noted FAA’s planned redundancy approach for the initial Salt Lake City configuration and the planned approach once Atlanta is upgraded with an AFTN/AMHS Gateway. For the Salt Lake City configuration of hardware redundancy of the AFTN/AMHS Message Switching Node, Router Redundancy, and Interface Redundancy was described. For the combined Salt Lake City and Atlanta configuration, redundancy using Manual procedures to redirect the RFC-1006 Gateway connections or X.25 circuits was introduced.

Conversion of X.25 to IP Network Protocol in the United States

3.28USA informed the meeting that the FAA domestic telecommunication network migrates from X.25 network protocol to Internet Protocol (IP) network to reduce cost in long run and to reduce the variety of interfaces. It was noted that some of the data-link applications being used by FAA will migrate to IP environment. Methods have been adopted to overcome the issue of message assurance inherent in IP protocol. It was assured that FAA still supports the AMHS service based on X.25 subnet as specified in ICAO Doc 9705.

Next meeting of the ATNIC Group

 

3.29Considering the need to further progress urgent tasks, the meeting agreed that the next Meeting of ATNICG Working Group will be hosted by Aerothai in Bangkok from 19 to 21 September 2007. Aerothai also offered to host the ATN/AMHS Implementation Seminar/Workshop in January 2008 in Chiangmai, Thailand. The next meeting of the ATN Implementation Co-ordination Group will be held in April 2008. The exact date and venue of the meeting will be coordinated with the States concerned and notified to the members of the ATNICG in the due course. The meeting expressed its appreciation and gratitude to the Department of Civil Aviation Hong Kong China for hosting the ATNICG/2 in Hong Kong China and for the excellent arrangements made for the meeting and the opportunity provided to visit the air navigation facilities at Hong Kong International Airport.

AIDC Review Task Force

The A

3.30The meeting reviewed the report of ATS Interfacility Data Communication Review Task Force Meeting (AIDC/TF) held in February in Bangkok, Thailand. The meeting was attended by 33 participants from 14 States. The meeting also reviewed the action taken by the ATM/AIS/SAR SG/17 meeting on the report of the Task Force. The meeting agreed to the changes proposed by the ATM/AIS/SAR Sub-group regarding the draft Version 3 ICD for AIDC. The meeting noted the changes proposed by the AIDC Review Task Force in Part II of the ICD regarding Communications and support mechanism. As result of review, the CNS/MET Sub-group jointly endorsed the draft Conclusion formulated by the AIDC Review Task Force for adoption of Version 3 of ICD for the AIDC.

Dissolution of the AIDC Task Force

3.31The meeting recognized that the terms of reference established by APANPIRG/5 for the AIDC Task Force had been completed. The Task Force meeting held in 2003 was conducted based on relevant Decisions of APANPIRG for guidance, rather than on any specific terms of reference. This was also the case for the meeting conducted in February 2007. In view of the foregoing, the meeting agreed that, having completed the draft of Version 3 of ICD for AIDC, the AIDC Task Force should be formally dissolved by APANPIRG. The meeting considered that there are still some outstanding matters with respect to ATN/AMHS Transition support as indicated in the section 3.2 of the Part II of the ICD which need to be further addressed. However, it was considered that such tasks could be included in the work programme of the ATN Implementation Coordination Group and CNS/MET Sub-group of APANPIRG. In view of the foregoing, the meeting developed the following draft Decision.

Draft Decision 11/8 - Dissolution of AIDC Task Force

That, having completed the Version 3 of the Asia/Pacific AIDC ICD in accordance with the APANPIRG Decision 17/13, the AIDC Task Force be dissolved. Any residual task with respect to ATN/AMHS transition support be dealt with by the ATNICG and CNS/MET Sub Groups of APANPIRG.

3.32The meeting also noted the AIDC related developments by OPLINK Panel, Aeronautical Communication Panel and ATNICG.

Upgrade of AFS between the USA and Australia

3.33The USA informed the meeting that the channel speed of the fixed circuit between Oakland, California, USA and Brisbane, Australia had been increased from 2.4 Kbps to 64 Kbps as previous bandwidth was insufficient to handle all message traffic. This action was undertaken to accommodate all circuit loading conditions and the inclusion of technical system improvements e.g. Air Traffic System (ATS) Message Handling System (AMHS) and Aeronautical Telecommunications Network (ATN). The circuit is planned to be placed in service by 19 July 2007. It was noted that the entire circuit between the United States and Australia is now provided by a single service provider. It was noted that the use of a single service provider for the entire end-to-end circuit will reduce the repair, restoration, and coordination problem. The information contained in the relevant FASID CNS Table and ASIA/PAC AFTN routing directory needs to be updated by the next consolidated amendment to the relevant documents.

Agenda Item 4: Aeronautical Mobile Service (AMS):

1) air-ground communication

2) implementation of data-link Flight Information Service (DFIS) Applications

3) discuss other AMS related issues

4.1 Under this agenda item, the meeting reviewed several information papers and working papers presented to the meeting.

Development of Data Link Harmonization Strategy

4.2Secretariat provided an information paper on the draft strategy for data-link harmonization and issues and resolutions associated with providing data-link services to ATN equipped aircraft in an FANS-1/A environment as contained in ICAO Europe and North Atlantic Regional Office letter issued in May 2007. It was recommended that if States are considering implementing ADS-C, they should implement either FANS 1/A’ ADS-C or implement the new “next generation” ADS-C under draft by the Data Link Steering Group (DLSG) in Europe. It was not recommended to implement other defined ADS-C, as it would be a divergent step and would not fix a number of known ADS-C shortcomings. If States are considering implementing CPDLC, recognizing Europe’s implementation, implement CPDLC under “next generation” CPDLC as discussed in the DLSG. It was not recommended to pursue partial or divergent CPDLC evolutions. Overall idea is to get a next generation CPDLC and ADS that allow migration of both FANS 1/A and ATN to a single standard. It was noted that in Asia/Pacific Region FANS 1/A requirements are being implemented in accordance with the decisions of APANPIRG. IFALPA was of the view that harmonization was a very important issue. The meeting generally supported the draft strategy for the data link harmonization to create a single next step rather than additional and divergent interim steps. The meeting agreed that issues and resolutions associated with data link services should be appropriately addressed. It was suggested that a copy of the above referred letter be provided to the various FANS implementation teams within the ASIA/PAC Region. i.e. FIT-BOB, FIT-SEA, ISPACG and IPACG, for comments.

Aeronautical Mobile Service (AMS) – Strategy

4.3Secretariat proposed a draft Aeronautical Mobile Service (AMS) Strategy for adoption by the meeting. The proposed strategy was based on the outcome of APANPIRG discussions at its Fourteenth Meeting held in August 2003 and outcome of ITU World Administrative Radio Conference (1979) regarding the allocation and utilization of frequency band 136 – 137 MHz.

4.4It was noted that APAPNPIRG/14 had recognized the following guidelines which would serve the States in their preparations for AN Conf/11 to deal with Agenda Item 7 from Asia/Pacific perspective (paragraph 2.2.35):

- A channel spacing of 25 kHz will continue to be operational specification in ASIA/PAC Region as it is expected to satisfy requirements for the foreseeable future

- The VHF voice service, backed by CPDLC and HF will be the primary communication medium for transcontinental traffic; and a combination of CPDLC and HF voice will be the communication medium for oceanic traffic

-

The requirements for basic voice communications will continue, supplemented by data link Flight Information Services (DFIS) applications including D-VOLMET, D-ATIS and PDC, which would significantly release pressure of VHF spectrum congestion.

4.5The 136 – 137 MHz frequency band has been reserved exclusively for VHF data-link applications in the Asia/Pacific Region to meet the data link requirement. In view of the foregoing, the meeting formulated the following draft conclusion:

Draft Conclusion 11/9 - Aeronautical Mobile (R) Service Strategy

That, the Strategy for Aeronautical Mobile (R) Service in the Asia/Pacific Region shown in Appendix H to the report be adopted and published.

Data Link SATCOM Services

4.6The status of the use of 30 NM Lateral and 30 NM longitudinal separations (30/30) in Oakland Oceanic FIR was presented by the United States. The findings of the 30/30 Scrutiny Group indicated that the initial trials were successful, with one exception. The exception was the reliability of the Perth Ground Earth Station (GES), which had suffered several outages over the course of the 30/30 trials. The associated operational impact of outages related to data-link services was discussed. It was expressed that there is a need to identify mechanisms to ensure adequate end-to-end performance of satellite communication systems which are used for the provision of Air Traffic Services like CPDLC, ADS-C etc. While the meeting supported the requirement of such mechanism, IATA was of the opinion that the service provider should assure continuity, redundancy and other operational parameters to continue such services, which are dependent on data-link availability. In this connection, Secretariat informed the meeting that some of performance requirements of such services are already included in the ‘Required Communication Performance (RCP)’. It was agreed that the requirements should be covered in the contract with the service provider. USA was of the view that for such essential services, the architecture of the system should be specified to ensure specified level of continuity and availability. The meeting also noted the result of discussions on the subject by the ATM/AIS/SAR/SG/17 meeting and the Draft Conclusion 17/20.

Phasing-out of 121.5 MHz Satellite Alerting Services

4.7Secretariat presented COSPAS – SARSAT decision to phase out the Satellite Alerting Services on 121.5 and 243 MHz from 1 February 2009. It was also informed that the Satellite Alerting service subsequent to 1 February 2009 will be available only to 406 MHz Emergency Locator Transmitter (ELT) equipped aircraft. The presentation described the Satellite Alerting services available on 121.5 MHz and 406 MHz and also brought out the relative advantages of service provided on 406 MHz over the service provided on 121.5 MHz. The requirement of registering all the ELT Beacons by States and different methodologies for registering the ELT were also discussed. The Secretariat was requested to bring to attention of ATM/AIS/SAR Sub-group the result of discussions by the meeting. In view of the foregoing, the meeting developed the following Draft Conclusion.

Draft Conclusion 11/10 - Registration of ELT Beacons

That, States be requested to designate a registering agency for registering ELT Beacons, coded with the country code of the State and unique code of that beacon in a database as specified in paragraph 5.3.2.2 of Annex 10 Volume III and the guidance provided in Appendix I to Chapter 5 ‘Emergency Locator Transmitter Coding’ of the Annex.

Guidance Material for Procurement and Implementation of Data link Systems

4.8The meeting recalled that the tenth meeting of the CNS/MET Sub-group had reviewed the draft guidance material for procurement and implementation of data link systems (including AFTN, ADS, CPDLC and AIDC) presented by New Zealand. It had been developed according to a decision of Regional Airspace Safety Monitoring Advisory Group (RASMAG). The guidance material focused on three primary areas including system procurement processes, implementation of systems and specification of data link systems. It was noted that the document had been prepared from users’ point of view which would provide common understanding and quick reference for procurement and implementation of data link ATM systems. The document would serve as one of the regional guidance materials. The meeting reviewed the final draft of the document as provided in Appendix B to the RASMAG/7 meeting’s report. The meeting suggested removing the last two sentence of the first paragraph of Chapter 5 of the guidance material starting with “Specifications produced by technical ….. operational suitability”. The meeting also suggested that material for DFIS should be included in the Guidance material in the future. The meeting appreciated the efforts made in making this regional guidance material available. The meeting noted the action taken by the ATM/AIS/SAR/SG/17 meeting on the Guidance Material. The meeting agreed to support the Guidance Material and jointly endorsed the following draft Conclusion for consideration by APANPIRG/18.

Draft Conclusion 11/11 - Guidance Material for the Asia/Pacific Region ADS/CPDLC/AIDC Ground Systems Procurement and Implementation

That the Guidance Material for the Asia/Pacific Region ADS/CPDLC/AIDC Ground Systems Procurement and Implementation shown in Appendix I to the Report be adopted and published as regional guidance material.

(13 pages)