The early years of the 21st century will see the start of advanced satellite navigation systems mapping the world.

From the Wide Area Augmentation System (WAAS) in North America, the European Geostationary Navigation Overlay System (EGNOS) and later, Galileo, and the Multi-function Transport Satellite (MTSAT) system in the Asia-Pacific region, satellite navigation systems are promising precision guidance for aeronautical operators worldwide.

The first of the new-generation satellite navigation systems augmenting the global positioning system (GPS) and Glonass satellite networks to come on line will be the long-awaited WAAS.

This has faced programme delays, funding problems and questions about its capabilities since the project was mooted in 1994. From September 2000, the system will be put to the test with the implementation of WAAS Phase I.

The first stage will provide en route navigation and vertical guidance for precision approaches at a limited number of runways in the USA.

The hardware for WAAS Phase I, including 25 ground reference stations, two master control stations, two geosynchronous satellite uplink stations and navigation transponders on two Inmarsat-3 satellites, is in place.

Commissioning of the system is set for 25 September, 2000.

WAAS will extend to Canada, the Caribbean, Mexico and Chile. It has also been developed to be interoperable with the European and Japanese satellite navigation systems to provide a seamless global system.

In Europe, the initial EGNOS operational capability has been set for 2002, with full operational capability now planned for 2005.

EGNOS will augment GPS/Glonass with signals to be broadcast via two Inmarsat-3 satellites and the Artemis spacecraft, providing a precision approach capability throughout Europe.

EGNOS has not received a warm reception from many of Europe's airlines, however, which argue that the system will not meet their objectives in terms of increased safety and capacity, and reduced costs and delays.

Europe's airlines are in favour of a jump to the second phase of the continent's global navigation satellite system programme - Galileo.

Galileo will be designed as an open, global system that is fully compatible with, but independent from, the GPS.

The system, which will comprise a medium Earth orbit satellite network developed as a public/private partnership, will be operational in 2008.

Europe's development of its own system means that it will not be reliant on the GPS and the continent will be able to benefit from a huge world satellite navigation market.

As former European Commission transport commissioner Neil Kinnock said when announcing Galileo: "As the Internet has revolutionised electronic communication, so global satellite systems are revolutionising navigation.

"Europe must put itself in a position to capture a fair share of a world market that could be worth an estimated €40,000 million [$41,150 million] within a few years."

Source: Flight International