The continued growth of traffic and the need to provide greater flight efficiency makes it necessary to optimize available airspace. This is being achieved world-wide by enhanced Air Traffic Management and by exploiting technological advancements in the fields of Communication, Navigation and Surveillance.
More specifically, the application of area navigation techniques in all flight phases contributes directly to improved airspace optimisation. Area navigation is enabled by the use of an on-board navigation computer commonly referred to as a RNAV system.
RNAV system capabilities are increasingly being exploited with a view to maximizing airspace resources. To this end, both flight crew and ATC need to understand RNAV system capabilities and ensure that these match airspace requirements. The use of RNAV systems lies at the core of Performance Based Navigation (PBN), which introduces approval requirements for use of these systems in airspace implementations.
ICAO’s Performance Based Navigation (PBN) Concept has replaced the RNP Concept; it was introduced
through publication of the ICAO PBN Manual (Doc 9613) in 2008. The PBN Concept is geared to respond to airspace requirements.
To these ends, ICAO’s PBN concept identifies three components:
– The Navigation Application,
– The Navigation aid (NAVAID ) Infrastructure and
– The Navigation Specification.
– PBN is a new concept based on the use of Area Navigation (RNAV) systems. Significantly, it is a move from a limited statement of required performance accuracy to more extensive statements of required performance in terms of accuracy, integrity, continuity and availability, together with descriptions of how this performance is to be achieved in terms of aircraft and crew requirements.
– The Required Navigation Performance (RNP) concept has been replaced by the PBN concept. Therefore, a lot of RNP terminology has been replaced by PBN terminology.
– The ‘Performance Based Navigation Manual’ replaces the ‘Manual on Required Navigation Performance (RNP) ICAO Doc 9613-AN/937’.
– Global definitions of terms are provided that are aimed at removing any previous regional differences.
– A set of globally compatible Navigation Specifications are also provided. These are to be used as a basis for local or regional Navigation Applications in the en route, terminal and approach environments.
– Increasingly, the Navigation (NAV) element of the Airspace Concept will be based on PBN.