Part A — Objectives and General Requirements

Transponder Code (TC):

1. The objectives of this function are:

(a) to improve the robustness of the code allocation process through allocation of clear roles and responsibilities to all involved stakeholders, with the overall network performance at the centre of code allocation determination;

(b) to provide increased transparency of code allocations and of the actual code usage enabling the better assessment of the overall network efficiency.

[...]

3. The CAA shall make available at all times to air navigation service providers an SSR transponder code allocation list that describes the complete and up-to-date allocation of SSR codes within the United Kingdom flight information regions.

4. A formal process for establishing, assessing and coordinating the requirements for SSR transponder code allocations shall be implemented by the CAA, taking into account all required civil and military uses of SSR transponder codes.

5. The formal process laid down in point 4 shall include, as a minimum, relevant agreed procedures, timescales and performance targets for the completion of the following activities:

(a) submission of applications for SSR transponder code allocations;

(b) assessment of applications for SSR transponder code allocations;

(c) coordination of proposed amendments to SSR code transponder allocations with neighbouring States;

(d) periodic audit of the code allocations and needs with a view to optimisation of the situation, including re-allocation of existing codes allocations;

(e) periodic amendment, approval and distribution of the overall SSR code transponder allocation list referred to in point 3;

(f) notification, assessment and resolution of unplanned conflicts between assignments of SSR transponder codes;

(g) notification, assessment and resolution of wrong assignments of SSR transponder codes, detected at code retention checks;

(h) notification, assessment and resolution of unplanned shortfalls in allocations of SSR transponder codes;

(i) provision of data and information in accordance with the requirements laid down in Part C.

[...]

7. The CAA shall ensure that SSR transponder codes are assigned to an aircraft in accordance with the SSR transponder code allocation list referred to in point 3 of Annex IV to Commission Implementing Regulation (EU) 2019/123 as that Regulation has effect in EU law as amended from time to time.

[...]

10. The Secretary of State must assist the Network Manager and air navigation service providers to agree on plans and procedures to support the periodic analysis and identification of future SSR transponder code requirements. That analysis shall include the identification of potential performance impacts created by any predicted shortfalls in the allocations of SSR transponder codes.

[...]

Mode S Interrogator Code (MIC):

12. The objectives of this process are the following:

(a) to perform a coordinated Mode S interrogator code allocation enabling the overall network efficiency;

(b) to provide the regulatory basis allowing better enforcement and oversight.

13. The CAA shall allocate the interrogator codes to civil and military Mode S interrogators in a manner that optimises the safe and efficient operation of air traffic surveillance and civil-military coordination taking the following into account:

(a) the operational requirements of all operational stakeholders;

(b) Commission Regulation (EC) No 262/2009;

(c) the required management of Mode S interrogator codes in compliance with the provisions of the European principles and procedures for the allocation of Secondary Surveillance Radar Mode S Interrogator Codes (IC) (ICAO EUR Doc 024)

[...]

15. The CAA shall provide a centralised interrogator code allocation service to Mode S operators through the interrogator code allocation system.

[...]

22. The Secretary of State must assist the Network Manager and Mode S operators to agree the plans and procedures to support the periodic analysis and identification of future Mode S interrogator code requirements. That analysis shall include the identification of potential performance impacts created by any predicted shortfalls in the allocations of interrogator codes.

[...]