Single European Sky (SES)

The Single European Sky project aims to harmonize air traffic control operations and system throughout Europe to improve efficiency, reducing delays due to air traffic control.

This project came as a response to the dramatic growth in air travel witnessed in the last two decades, to which end the European Commission passed two Single European Sky packages to create a legislative framework for European aviation.

With the Single European Sky second package (SES II), a step forward was made towards establishing targets in key areas of safety, network capacity, effectiveness and environmental impact.

On the technology side, SES is supported by the Single European Sky ATM Research (SESAR) Programme, which will provide advanced technologies and procedures with a view to modernizing and optimizing the future European ATM network.

More information about the Single European Sky and SESAR can be found at:



Regulation No. 11/2009  on interoperability (EC Regulation no 552/2004) lays down requirements which provide a unique set of standards for air traffic control components and systems across Europe – ensuring that the systems of one country are fully compatible with those of another.

Interoperability applies to the following air navigation systems and constituents which are part of the European Air Traffic Management Network (EATMN):

  1. Systems and procedures for airspace management.
  2. Systems and procedures for air traffic flow management.
  3. Systems and procedures for air traffic services, in particular flight data processing systems, surveillance data processing systems and human-machine interface systems.
  4. Communications systems and procedures for ground-to-ground, air-to-ground and air-to-air communications.
  5. Navigation systems and procedures.
  6. Surveillance systems and procedures.
  7. Systems and procedures for aeronautical information services.
  8. Systems and procedures for the use of meteorological information.

The NSA is responsible to oversee the compliance of the Service Providers with the Interoperability Regulation when introducing changes to their ANS systems and for existing systems.

The Service Providers have to provide a repository (list) of current ATM Systems, define what is considered a System and what is considered a Constituent with respect to interoperability.

The following links provide guidance to Air Navigation Service Providers:



EC Declaration of Conformity (doc)

EC Declaration of Suitability for use (doc)

EC Declaration of Verification (doc)


08-2021 amending CAA Regulation 07/2018 laying down requirements on aircraft identification for surveillance for the single European sky and CAA Regulation 03/2018 laying down requirements for the performance and the interoperability of surveillance for the single European sky
08-2017 Common rules on air traffic flow management

Technical Publications