Federal Radionavigation Plan-pie in the sky for civil aviation?

The Federal Radionavigation Plan states that all present navigation and landing guidance facilities will be retired starting in 2005, and full dependence for these functions will be placed on augmented GPS. Once this is implemented, civil aviation will be totally vulnerable to terrorist jammimg of the GPS signals over wide Earth areas with widespread disruption of air traffic and potential disasters. It has also become apparent that the use of GPS/GNSS is complex and expensive for the required civil aviation functions. It is clear that a different system form is needed for civil aviation. A redundant satellite/ground based system that will prevent it from being a jamming target while providing ATC surveillance, navigation, collision warning/avoidance, high-speed data link and Cat.I landing guidance globally, plus precision Cat.III guidance in the terminal areas as needed. Such a system, the Integrated Global Surveillance and Guidance System (IGSAGS), is described