ATC Operational Uses for Autoinatic Altitude Reporting

Surveillance radar provides the air traffic controller with only a two-dimensional picture of traffic in a three-dimensional environment. Recently, the Federal Aviation Agency embarked upon the development of an automatic altitude-reporting capability utilizing radar beacon. Its addition to the system will enable presentation of both specific aircraft identification and altitude in alpha-numeric symbology directly on the controller's radarscope adjacent to related radar targets. Operational requirements for this new tool indicate a future capability of reporting altitude from the surface to 100,000 feet in 100-foot increments. The three-dimensional capability achieved will minimize the need for pilots to make verbal position reports, and will virtually eliminate reports with regard to altitude alone. Giving the controller this capability will reduce the need for arriving and departing aircraft to level out during descent and climb in order to maintain altitude separation from others on conflicting courses. While the aircraft is enroute, altitude change will be much less a problem to the controller, permitting the pilot much greater freedom in selection of optimum cruising altitudes. Automatically reported altitude data is essential to the sophisticated computerized environments being developed for reducing ATC bottlenecks.