# Commission Regulation (EC) No 262/2009 of 30 March 2009 laying down requirements for the coordinated allocation and use of Mode S interrogator codes for the single European sky (Text with EEA relevance), Article 3: Interoperability and performance requirements

Extent: E+W+S+N.I.

Mode S operators shall ensure that the radar head electronics constituent of their Mode S interrogators using an operational interrogator code:
1.. support the use of SI codes and II codes in compliance with the International Civil Aviation Organisation provisions specified in Annex I point 1;
2.. support the use of II/SI code operation in compliance with the requirements specified in Annex III.

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Source: https://www.legislation.gov.uk/eur/2009/262/article/3 (the official version)
Page: https://openlegislation.uk/eu-regulation-2009-262/article-3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.