This Opinion proposes regulatory amendments pertaining to two different subject matters in support of operations in the single European sky (SES): the use of Airborne Collision Avoidance System (ACAS) Xa and the harmonised use of performance-based navigation (PBN) specifications for oceanic and remote continental operations.
The proposed amendments introducing the use on a voluntary basis of ACAS Xa within the SES, based on the transposition of related ICAO Standards and Recommended Practices (SARPs), are expected to increase safety, and to improve harmonisation.
The proposed amendments on PBN would allow the use in the SES of ICAO RNAV 10 and RNP 4 navigation specifications, which have been specifically designed to support operations in en-route oceanic and remote continental airspace. The use of RNAV 10 and RNP 4 instead of RNAV 5, which is the only specification recognised for use in SES, is expected to preserve the required level of safety through more stringent aircraft requirements against the loss of the navigation function (continuity failure). In this regard, the proposed amendments would keep the aircraft performance compatible with the air traffic services (ATS) and communication, navigation, and surveillance (CNS) services available in such airspace.
