France publishes its first GNSS approach

 - February 5, 2007, 5:42 AM

The French civil aviation authority, DGAC, has published the first GNSS nonprecision approach procedure for a French airport and is working toward introducing approaches with vertical guidance (APVs) once the necessary augmentation of the GPS signals is available and the relevant ICAO design criteria become effective.

Stephane Dubet, head of the R&D division in the DGAC’s aeronautical information service (SIA), said in Maastricht that the French strategy had been to start with GNSS-based nonprecision approaches (NPA-GNSS), which rely on GPS signals plus receiver autonomous integrity monitoring, otherwise known as the airborne-based augmentation system. By the end of this year the DGAC hopes to have approval for the implementation of precision area navigation (PRnav), which will enable it to introduce PRnav standard instrument departures and standard arrivals.

The European geostationary navigation overlay service (EGNOS) is expected to be operational late next year or early in 2007. The ICAO procedure design criteria for APV approaches take effect in November next year, so the necessary space-based augmentation system and the guidance material for approach design should be in place at about the same time.

The DGAC’s first implementation of a GNSS approach was at Paris Charles de Gaulle, on an experimental basis and usable only by Air France. The first public procedure was published last year for the French dependency of St. Pierre in the St. Lawrence estuary. The first for airports in metropolitan France were those for Lyon-Bron, which became effective on February 3, and Lille, which was designed by the SIA’s new satellite central office and published on February 3 with an effective date of March 17. As many as 10 more approvals should follow this year, among them Brest, Biarritz, Toulon, Limoges and Lyon-Baron.

Europe has been relatively slow to implement GNSS approaches, largely because of the abundance of conventional radio navaids. That may change once EGNOS and the APV II design criteria are available, since APV II approaches are intrinsically safer than nonprecision approaches and can be conducted to lower minimums. EGNOS-based APVs should be flyable using certified WAAS receivers.