Air Traffic Controllers

The goal of the first air traffic control efforts—beacon lights—was to guide airplanes along a specified airway. As airways and aircraft grew in number, radio communication and radio beacons were added to help planes navigate and to provide weather forecasts. In 1936, the federal government opened the first air traffic control center to regulate the increasing numbers of aircraft flying into and out of the country's growing airports. The instrument landing system, a method for signaling aircraft, was instituted in 1941. Airplanes were reaching higher speeds and altitudes, and the controllers' functions became more important to guard against collisions, to ensure safe landings, and to warn pilots of potential weather and geographic hazards in flights. Radar, developed during World War II, allowed air traffic controllers to track the movements of many aircraft and for longer distances. The air traffic control network was extended to include centers at airports, en route centers, and flight service stations, each of which performed specific tasks and controlled specific portions of the skies. After the war, more sophisticated communication systems were developed, including VOR (very high frequency omnidirectional range) transmission, which was used to signal flight path data directly to the plane. Computers were soon installed in order to provide still greater accuracy to the air traffic controller's instructions. Development of the global positioning system (GPS), however, has made it possible for airplanes to achieve greater control over their flight paths, so fewer air traffic controllers will be needed.