MUNICH — A European network to complement signals sent by the U.S. GPS satellite navigation constellation was declared certified March 2 for use by European civil-aviation authorities, giving Europe’s satellite navigation managers a welcome respite from their system’s ongoing financial trials.

In certifying the satellite and ground network as ready to guide civil aircraft to runway landings with precise vertical accuracy, European officials were able to complete ”the first concrete realization” of years of work on the regional system and their planned global Galileo navigation constellation, said Charles Villie, EGNOS project manager at the European Commission.

EGNOS, or European Geostationary Navigation Overlay System, comprises 40-plus ground stations linked to three satellites in geostationary orbit over the equator equipped with EGNOS terminals. EGNOS enhances the reliability and accuracy of U.S. GPS signals, permitting civil-aviation authorities to continue their planned move away from ground-based navigation aids toward satellite guidance.

The International Civil Aviation Organization, based in Montreal has set detailed reliability standards for regional GPS-overlay systems like EGNOS. EGNOS is the European equivalent to the U.S. Wide-Area Augmentation System, WAAS, which has been in service for six years and has been adopted by more than 40,000 airports in North America.

Similar systems are being built by Japan, Russia and India.

The EGNOS ground network was built by Thales Alenia Space of France and Italy and financed by the European Commission, the 18-nation European Space agency and Eurocontrol, Europe’s civil-aviation authority.

Now that it is certified, it will be up to each European nation’s national aviation body to install the necessary hardware to permit EGNOS-guided operations at their airports.

“Today’s certification ends 15 years of development,” Villie said in Munich March 2 at the Munich Satellite Navigation Summit. “It is now up to Europe’s aviation authorities to develop procedures [for EGNOS] as called for under the Single European Sky regulation. Our message now is: EGNOS is here: Use it.”

EGNOS signals were released for uses not including safety-of-life applications in October 2009. Aviation users have among the strictest requirements for satellite-based navigation.

Still uncertain is the long-term financing of EGNOS and the larger Galileo global navigation constellation of satellites. The European Commission in January said it is likely to cost some 110 million euros ($150 million) per year to operate and maintain EGNOS. This money has not been secured beyond 2013.

Peter B. de Selding was the Paris bureau chief for SpaceNews.