Global Positioning System - Challenges in Sustaining and Upgrading Capabilities Persist: Gao-10-636 (Paperback)

The Global Positioning System (GPS) provides positioning, navigation, and timing (PNT) data to users worldwide. The U.S. Air Force, which is responsible for GPS acquisition, is in the process of modernizing the system. Last year GAO reported that it was uncertain whether the Air Force could acquire new satellites in time to maintain GPS service without interruption. GAO was asked to assess (1) the status of Air Force efforts to develop and deliver new GPS satellites, the availability of the GPS constellation, and the potential impacts on users if the constellation availability diminishes below its committed level of performance; (2) efforts to acquire the GPS ground control and user equipment necessary to leverage GPS satellite capabilities; (3) the GPS interagency requirements process; and (4) coordination of GPS efforts with the international PNT community. To do this, GAO analyzed program documentation and Air Force data on the GPS constellation, and interviewed officials from DOD and other agencies.