Every day, the Federal Aviation Administration provides air traffic service to more than 45,000 flights and 2.9 million airline passengers traveling across the more than 29 million square miles that make up the U.S. national airspace system (NAS).
The NAS is a network of both controlled and uncontrolled airspace, both domestic and oceanic. It also includes air navigation facilities, equipment and services; airports and landing areas; aeronautical charts, information and services; rules and regulations; procedures and technical information; and manpower and material.