Understanding EGNOS

MELANIE VRITSCHAN, UMBERTO GUIDA, JON WESTBROOK

Finally, the EC Regulation 552/2004 about the interoperability of the European Air Traffic Management network (the “Interoperability regulation”) require the achieved performance and safety requirements to be documented. On this purpose, the European GNSS certified service provider issues to his NSA a “declaration of verification”, together with a technical file, which confirm the compliance to the implementing rules for interoperability in order to make the system be integrated in the EATMN; such implementing rules could need to be specifically issued for the GNSS. Such “declaration of verification” contains also the “declaration of conformity” or “suitability use” of the system constituents to the implementing rules.

Important inputs for the preparation of the technical file for the “declaration of verification” are the EGNOS Safety Cases. The EGNOS System Safety Case has been developed by ESA and will be updated with each new ESR. During the Initial Operations Phase, ESSP is working on the development of the EGNOS Operation Safety Case, which will be maintained throughout the system’s life time.

The challenges and issues to be tackled with regards to EGNOS certification are the following:

* Clarification of the service provision organizational scenario
* Designation of the authority and responsibility
* Provider’s certification by the competent National Supervisory Agency supported by Notified body/ies
* Clarification of liability issues
* Issues linked to the complexity and number of different actors involved
* Necessary time scales for the certification process

Major European actors are working together to develop the EGNOS certification framework on the basis of such legislation:

# GNOS Certification Task Force has been established and follows the safety cases development
# Analysis of the service provision chain
# ESSP is working in collaboration with National Supervisory Agencies (NSAs)