Peer Reviews

Peer Reviews


As part of the European Community’s plan for the implementation of a Single European Sky (SES), and in accordance with Article 9 of Commission Regulation (EC) 2096/2005 laying down common requirements for the provision of air navigation services (replaced by Regulation EU No 1035/2011, which, in turn, was repealed by Regulaiton 2017/373), a Peer Review process has been implemented in 2010 to assist National Supervisory Authorities (NSAs) in improving the performance of their role. While the process addresses all NSA arrangements - both safety and non-safety - an initial specific focus is placed on safety oversight processes, where detailed regulatory provisions exist in Regulation 2017/373.

Basis for Further Safety Improvement

Peer Reviews provide new safety benefits, beyond those provided by audit schemes of States / NSAs. Rather than duplicating existing programmes, the process adopts a “teach and learn” approach, and facilitates continuous improvement and cooperation between NSAs. This is achieved by reviewing the practical application of arrangements, and their performance, identifying strong points, areas for improvements and lessons learned, leading to harmonisation of processes and identification and sharing of best practice.

In the medium term, the mechanism has the potential to effectively address the continuous improvement of NSA arrangements as part of the performance-based approach introduced by SES II. In particular, the process of developing FABs may unquestionably benefit from synergies and the sharing of best practices among NSAs.

Conceptually, peer reviews provide an opportunity to review the lessons from safety audits and the corrective actions intended to address audit findings. In that regard, ESIMS and ICAO USOAP reports, LSSI information, etc. provide key inputs to the reviews.

The Common requirements for the provision of air navigation services set conditions in terms of minimum number of reviewers in a peer review team. While the arrangements for the reviews are a task for the European Commission, they are to be conducted by national experts designated by Member States. Hence, in April 2009, the EC formally invited the NSAs to nominate experts whose competence should collectively cover all aspects of the Common requirements.


The scope of the peer reviews carried out during the first round (2010 - 2012) covers the principal tasks performed by the NSAs in respect of:

  • Regulation (EC) 552/2004 (the interoperability Regulation)
  • Commission Regulation (EC) No 1034/2011 on safety oversight in ATM
  • Commission Regulation (EU) No 1035/2011 laying down the common requirements for the provision of ANS, focusing on oversight of changes, interoperability, NSA human resources and on-going compliance from the perspective of certification renewal.

Despite the invitation to participate, it has been identified that neither the EC nor the NSAs have the means to put in place and operate continually such a process requiring, as a minimum, a defined structure to plan and support its implementation. Considering the complexity of conducting peer reviews, the Single Sky Committee (SSC) recognised the advantages of arranging support from the EUROCONTROL (SRC/SRU).

Bearing in mind the experience of the ESARR Implementation Monitoring and Support (ESIMS) Programme terminated by the end of 2012, which used to operate a schedule of on-site audits focused on NSAs, EUROCONTROL supported the peer review process using the available means of ESIMS, but in a way that provides the possibility for these initial arrangements to evolve further. The EUROCONTROL support included:

  • Development of the peer review methodology, plus guidance material;
  • Establishment of appropriate timetables;
  • Maintenance of a database of NSA experts to participate in the reviews;
  • Training for peer reviewers;
  • Operation of a database to collect and support the follow-up and dissemination of reviews results;
  • Appointment of EUROCONTROL experts as facilitators;
  • Provision of secretarial and logistical support.

In consideration of the identified lack of resources of NSAs, proposed schedules took into account that peer reviews should not coincide with ICAO USOAP audits and EASA standardisation inspections, with the separation in planning the various visits to States being appropriately identified well in advance. The first round of peer reviews was carried out at FAB level in the period 2010 - 2012.

No further peer reviews were undertaken since then.

Further Reading

European Commission



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