ATM: the only constant is change

The Federal Aviation Administration (FAA) is updating the air traffic management (ATM) system to deal with the increasing aviation traffic. The FAA is modernizing the ATM equipment by replacing the ground-based automation equipment and phasing out the ground-based navigation sites. This automation will increase the rate of arriving and departing aircraft and enable free flight. Air-to-ground digital data links will replace air-to-ground voice communication and the space-based Global Positioning System will be used for navigation.