Setbacks to the US Federal Aviation Administration's satellite navigation centrepiece - the Wide Area Augmentation System (WAAS) - just won't go away.

The WAAS, designed to allow the US National Airspace System (NAS) to move away from its reliance on ground-based navigation aids to more accurate and efficient satellite-based ones, has been plagued with problems since its birth in 1994. Developing and certificating WAAS was never going to be an easy task, though, due to the complexity and the unknown factor associated with such a pioneering system.

But, as problems with WAAS continue, so too will confidence in it deteriorate and the FAA now needs to tackle this issue as closely as the WAAS technical issues. WAAS has had its share of problems from the beginning, starting with a contractor switch when Wilcox Electric failed to resolve early problems and Hughes Aircraft (now Raytheon) was brought in.

Budget problems have never gone away, while last year's software difficulties meant WAAS is already two years behind its original schedule, now likely to rise to three years. The USA has little choice but to persevere with its satellite navigation efforts. Far too much money has been spent on WAAS for the FAA to give up, while air traffic control problems are increasing every year, necessitating drastic changes to the NAS.

Nevertheless, WAAS continues to be developed under a cloud of uncertainties. The FAA is working hard to resolve the technical issues and justify WAAS' existence to Congress, but it should now embark on a confidence-building mission to ensure that the aviation industry has as much faith in the system as the FAA has.

Europe, it is to be hoped, is also watching and learning from the US experience, ensuring that the global satellite navigation ride from here on will be a smoother one.

Source: Flight International