Title: Area Navigation Systems - SKYbrary Aviation Safety
Headings: Area Navigation Systems
Area Navigation Systems
RNAV
Description
Further Reading
EUROCONTROL
CASA
DGCAA (France)
AirServices Australia
ICAO
FAA
ATSB Australia

Content: Then, as the constellation is built-up, new services will be tested and made available, with system completion scheduled for 2020. Although the use of GNSS input for RNAV has made this method of navigation truly global, it has led to the availability of a very wide range of accuracy in RNAV - and therefore the uses to which it can be put - depending on how GNSS data is used. RNAV use of GNSS varies from hand held GPS, as an aid to day Visual Flight Rules (VFR) navigation, to the use of approach procedures which meet the highest accuracy and integrity standards of RNP-RNAV. In Europe, Basic Area Navigation (B-RNAV) has been in use since 1998 and is mandated for aircraft using higher level airspace. It requires a minimum navigational accuracy of +/- 5nm (RNP=5) for 95% of the time and is not approved for use below Minimum Sector Altitude. European standards for Precision Area Navigation (P-RNAV) are now also defined - a navigational accuracy of +/- 1nm (RNP=1) for 95% of the time. Qualifying systems must have the ability to fly accurate tactical offsets, P-RNAV routes must be extracted directly from the FMS data base and must be flown by linking the R-NAV system to the Flight Management System / Autopilot. As well, flight crews are restricted from manually adding waypoints to the route. This level of navigation accuracy can be achieved using DME/DME, VOR/DME or GPS. It can also be maintained for short periods using IRS (the length of time that a particular IRS can be used to maintain P-RNAV accuracy without external update is determined at the time of equipment certification).