Radar and radio, used since World War II to track aircraft from the ground, will eventually give way to a new satellite-based navigation technology, the government said Tuesday.

Federal Aviation Administrator Marion Blakey said developing a system based on the new technology is critical to the future of aviation.

"It's the way we're going to be addressing the horrific congestion we expect to see," Blakey told reporters. "It's the FAA's moon shot."

The FAA plans to spend $80 million for the next budget year and a total of $300 million within four years to go beyond the current experimental stage. By 2010, the system will be operational in 10 percent to 15 percent of the U.S. airspace, said Vincent Capezzuto, manager of FAA's surveillance and broadcast services.

Replacing the current radar-and-radio air traffic control system with one that relies on satellites will require billions of dollars and take up to 20 years, according to the FAA.

The satellite-based system, known as automatic dependent surveillance broadcast, or ADSB, includes a cockpit locator that determines an aircraft's precise location using the Global Positioning System. Once per second, a transponder sends that information to a ground station, which relays it to air traffic control.

Pilots can see the same visual display in the cockpit that air traffic controllers see on the ground, showing the aircraft's precise location as well as the weather and the location of other aircraft nearby.