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Article 3e Allocation of Mode S interrogator codes

Cover Regulation · Regulation (EU) 2017/373 · EAR revision 12 Mar 2025

IRImplementing rule

Article 3eAllocation of Mode S interrogator codes

1.Member States shall ensure that changes to the allocation of an interrogator code resulting from an update to the interrogator code allocation plan are communicated to the relevant Mode S operators under their authority within 14 calendar days from the day of receipt of the updated interrogator code allocation plan.

2.Member States shall make available to other Member States, at least every 6 months through the interrogator code allocation system, an up-to-date record of the allocation and use of interrogator codes by the eligible Mode S interrogators within their area of responsibility.

3.Where an overlap exists between the coverage of a Mode S interrogator located within the area of responsibility of a Member State and the coverage of a Mode S interrogator located within the area of responsibility of a third country, the Member State concerned shall:

(a)ensure that the third country is informed about the safety requirements related to the allocation and use of interrogator codes;

(b)take the necessary measures to coordinate the use of interrogator codes with the particular third country.

4.A Member State shall notify the air traffic service providers under its jurisdiction of Mode S interrogators operating under the responsibility of a third country for which the allocation of Mode S interrogator codes has not been coordinated.

5.Member States shall check the validity of the interrogator code applications received from the Mode S operators before making interrogator codes available through the interrogator code allocation system for coordination as laid down in point 15 of Annex IV to Commission Implementing Regulation (EU) 2019/123 ().

6.Member States shall ensure that the Mode S operators, other than surveillance service providers, comply with point CNS.TR.205 in Annex VIII.

7.The requirements laid down in paragraphs 1 to 6 shall not apply in the Single European Sky airspace that is not part of the International Civil Aviation Organisation (ICAO) European (EUR) region.

IR · Article 3e — Regulation (EU) 2017/373 · Regulation (EU) 2023/1771 · ATM/ANS Easy Access Rules · EAR revision 12 Mar 2025

All rules in Powers and recitals

Consolidated from the EASA Easy Access Rules (revision 12 Mar 2025, extracted 17 Aug 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.

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