Guidelines to ANC Panels for the Development of Sarps Material for Complex Systems

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AERONAUTICAL COMMUNICATIONS PANEL (ACP)

Eleventh MEETING OF THE AERONAUTICAL COMMUNICATIONS PANEL WORKING GROUP M

Montreal, Canada 31 May – 2 June 2006

Guidelines for the development of SARPs material for complex systems

(Presented by the Secretariat)

1. INTRODUCTION

1.1 The appendices of Assembly Resolution A35-14 constitute the current “Consolidated statement of continuing ICAO policies and associated practices related specifically to air navigation”. Appendix A to the Resolution (A35-14/App. A) contains the ICAO policy on the formulation of Standards and Recommended Practices (SARPs), and is reproduced as Attachment A to this paper.

2. discussion

2.1 On 3 March 2005, the Air Navigation Commission (ANC) requested the Secretary to examine the restructuring of Annexes and the “Guidelines to ANC Panels for the Development of SARPs Material” (ANC Procedural Guidebook, Attachment 1 to Chapter 4), in light of Resolving Clause 3 of A35-14/App. A, and prepare a paper for consideration by the ANC Working Group on Procedural Matters (WGPM).

2.2 A Secretariat paper containing proposed changes to the Guidelines was accordingly developed and submitted to the ANC WGPM (9 November 2005). The WGPM reviewed and amended the Secretariat proposal. The conclusions of the WGPM were submitted to the ANC, which approved the final version of the amended Guidelines on 19 January 2006. The amendments were included in the ANC Procedural Guidebook on 9 February 2006.

2.3 The Attachment B to this paper contains the amended Guidelines. Guidelines for new SARPs are in Section 3 of the attachment. Guidelines for existing SARPs are in Section 4.

3. ACTION BY THE MEETING

3.1 The ACP WGM is invited to note the attached guidelines and apply them to the development of Annex 10 material.

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ATTACHMENT A

A35-14:Consolidated statement of continuing ICAO policies and associated practices related specifically to air navigation

[…]

APPENDIX A

Formulation of Standards and Recommended

Practices (SARPs) and Procedures for

Air Navigation Services (PANS)

Whereas Article 37 of the Convention on International Civil Aviation requires the Organization to adopt and amend international Standards and Recommended Practices and Procedures and states the purpose of and the matters to be dealt with in that action, and Articles 38, 54, 57 and 90 contain additional relevant provisions;

Whereas the Assembly deems it advisable to establish certain policies to be followed in complying with these provisions of the Convention; and

Whereas the terms “Standard” and “Recommended Practice” have the following meanings:

Standard — any specification for physical characteristics, configuration, matériel, performance, personnel or procedure, the uniform application of which is recognized as necessary for the safety or regularity of international air navigation and to which Contracting States will conform in accordance with the Convention; in the event of impossibility of compliance, notification to the Council is compulsory under Article 38 of the Convention; and

a) Recommended Practice — any specification for physical characteristics, configuration, matériel, performance, personnel or procedure, the uniform application of which is recognized as desirable in the interest of safety, regularity or efficiency of international air navigation and to which Contracting States will endeavour to conform in accordance with the Convention;

The Assembly resolves that:

1. SARPs and PANS shall be amended as necessary to reflect changing requirements and techniques and thus, inter alia, to provide a sound basis for regional planning and the provision of facilities and services;

2. subject to the foregoing clause, a high degree of stability in SARPs shall be maintained to enable the Contracting States to maintain stability in their national regulations. To this end amendments shall be limited to those significant to safety, regularity and efficiency, and editorial amendments shall be made only if essential;

3. SARPs and PANS shall be drafted in clear, simple and concise language. For complex aeronautical systems, SARPs shall consist of broad, mature and stable provisions specifying system-level, functional and performance requirements that provide for the requisite safety levels and interoperability. For such systems, any technical specifications necessary to achieve these requirements shall be appendices to Annexes. Any related detailed technical specifications shall be placed in separate documents and be referenced in Annexes by means of notes;

4. in the development of SARPs, procedures and guidance material, ICAO should utilize, to the maximum extent appropriate and subject to the adequacy of a verification and validation process, the work of other recognized standards-making organizations. Where deemed appropriate by the Council, material developed by these other standards-making organizations should be referenced in ICAO documentation;

5. to the extent consistent with the requirements of safety and regularity, Standards specifying the provision of facilities and services shall reflect a proper balance between the operational requirements for such facilities and services and the economic implications of providing them;

6. Contracting States shall be consulted on proposals for the amendment of SARPs and PANS before the Council acts on them, except when the Council may deem urgent action to be necessary. Furthermore, subject to the adequacy of the verification and validation process, technical specifications for complex systems may be acted upon by the Council without consultation with States. Such material shall however be made available to States upon request;

7. the applicability dates of amendments to SARPs and PANS shall be so established as to allow the Contracting States sufficient time for their implementation; and

8. unless exceptional circumstances dictate otherwise, the applicability dates of amendments to Annexes and PANS shall be so established as to avoid the need for Contracting States to amend their national regulations more often than twice per calendar year. In the application of the foregoing, whenever practicable, any one Annex or PANS document shall not be amended more frequently than once per calendar year.

Associated practices

1. The Council should ensure that provisions of SARPs and PANS are completely consistent with each other. Furthermore, the Council should endeavour to improve the processing, presentation and usefulness of ICAO documents containing SARPs, PANS and other related provisions, especially for complex systems and their associated applications. To that end the Council should promote the development and upkeep of broad system-level, functional and performance requirements. The Council should continue seeking the most appropriate means of development, processing and dissemination of technical specifications for complex systems.

2. Contracting States should comment fully and in detail on the proposals for amendment of SARPs and PANS or at least should express their agreement or disagreement on their substance. They should be allowed at least three months for this purpose. Furthermore, Contracting States should receive at least thirty days of notification of the intended approval or adoption of detailed material on which they are not consulted.

3. Contracting States should be allowed a full three months for notifying disapproval of adopted SARPs amendments; in establishing a date for notifying disapproval the Council should take into account the time needed for transmission of the adopted amendments and for receipt of notifications from States.

4. In the application of the provision in Resolving Clause 8 above, the Council should ensure that, whenever practicable, the interval between successive common applicability dates of amendments to Annexes and PANS is at least six months.

B1

ATTACHMENT B

GUIDELINES FOR THE DEVELOPMENT OF SARPs MATERIAL

FOR COMPLEX SYSTEMS

(Approved by the Air Navigation Commission (171-2))

1. Background

1.1 The present guidelines are intended to assist the application of the ICAO policy addressing the formulation of SARPs material for complex systems and contained in Appendix A of the consolidated statement of continuing ICAO policies and associated practices related specifically to air navigation.

1.2 The intent of the policy is to ensure that ICAO provisions for complex aeronautical systems (such as communication, navigation and surveillance (CNS) systems) can be managed efficiently notwithstanding increasing technical complexity.

1.3 To this end, the policy establishes a three-level hierarchical structure of increasingly detailed requirements and specifications for complex systems:

1st level: “Core” SARPs in Annexes consisting of broad, mature and stable provisions specifying system-level, functional and performance requirements that provide for the requisite safety levels and interoperability;

2nd level: Any technical specifications in appendices to Annexes necessary to achieve requirements of core SARPs; and

3rd level: Related detailed technical specifications in separate documents, published by ICAO or other organizations, and referenced in Annexes by means of notes.

2. Detailed guidelines

2.1Guidelines for application of the ICAO policy are provided below addressing respectively new SARPs and existing SARPs.

3.Guidelines for new SARPs

3.1From the inception of development of ICAO material for a new system, the material should be planned to conform to the three-level structure established by the ICAO policy. The size of the material in the first two levels should be limited to the extent possible, as discussed below.

3.2The material contained in “core” SARPs (first level) should be limited to:

b) general definitions of terms;

c) general system characteristics and performance requirements;

d) where applicable (Annex 10), high-level radio-frequency characteristics (as required for the purpose of demonstrating conformance with relevant ITU Radio Regulations); and

e) reference(s) to appendix material (second level) and/or non-SARPs material (third level) as required.

3.3This material is not expected to exceed ten pages per system.

3.4Any additional technical specifications applicable to the system should be contained in the remaining two levels of the structure (appendix to an Annex and other non-Annex material, respectively).

3.5In apportioning the additional specifications between the second and third levels, an effort should be made to limit to the extent possible the size of the material in the second level (appendix), by including in it only those additional provisions that are necessary in practice to achieve interoperability. Such provisions need not include the full amount of technical detail which would be theoretically necessary to ensure the requisite safety levels and interoperability (e.g. definition of all message formats down to the bit level), as long as they identify unequivocally the technology selected and direct users to appropriate technical documents (third level) external to the Annex, by means of notes referencing those documents.

3.6The possibility of dispensing with second level material altogether (by locating in the third level all material that does not fall into the “core” category) should be actively explored, in close coordination with the ICAO bodies that define the applicable operational requirements.

3.7With regard to the identification of appropriate third level material (non-SARPs), two alternatives are available:

f) development of additional ICAO documents (other than SARPs), e.g. technical manuals; or

g) use of references to external (non-ICAO) material developed by other standards-making organizations.

3.8Selection of the preferred alternative (or of a combination of both) should be conducted on a case-by-case basis at the inception of the development of ICAO SARPs for a new system. The selection should be based on an assessment of the relative advantages and disadvantages of the alternatives. In general, use of references to external material is considered preferable over the development of additional ICAO documents when the following conditions can be met:

h) external material is available covering the whole system or individual elements of the system;

i) there is international consensus on the external material;

j) an adequate validation and verification process has been completed and an appropriate process is in place to ensure that ICAO is made aware of updates to the external material;

k) the terminology and content of the applicable SARPs material and those of the external material are harmonized;

l) the external material is accessible to the public (e.g. available for sale to the public).

3.9If necessary to facilitate the use of external material, consideration should be given to postponing the finalization of ICAO SARPs until the external material is available and stable.

3.10To facilitate the achievement of international consensus on non-ICAO material, the Secretariat should secure full access to the material and reasonable visibility on its development process and endeavour to make the material available to all parties involved in the SARPs development process.

3.11If external material is not available to cover all the elements of a new system, consideration should be given to using the external material to address individual elements of the system (such as airborne elements, radio interface characteristics etc).

3.12If the validation of the external material leads to the identification of content that is inappropriate for reference in association with ICAO SARPs, where practical, consideration should be given to the development of a list of exceptions to the external material, for inclusion in the ICAO material referencing the external material.

4.Guidelines for existing SARPs

4.1In the case of existing SARPs, developed before the entry into force of the current ICAO policy on formulation of SARPs, and whose structure is not fully aligned with the current policy, a systematic restructuring of the material to match the structure defined in the current policy is in general not recommended. This is because such a restructuring would in principle be inconsistent with the need for a high degree of stability in SARPs (also an element of the ICAO policy), and furthermore would be likely to require substantial effort. Instead, such restructuring should be accomplished gradually by considering specific subjects on a case-by-case basis, if additional benefits can be gained without excessive detriment to stability.

4.2 For instance, when developing new SARPs having substantial elements of commonality with existing ones (e.g. new generation technology to complement or replace a previous generation of the same technology), consideration should be given to aligning the structure of the existing SARPs to the new ones to highlight the elements of commonality. Similarly, if the level of detail of existing SARPs for a system or family of systems proves unnecessarily restrictive and technology-specific, thereby preventing the achievement of benefits to safety and efficiency, consideration should be given to replacing the detailed material with broader provisions.

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