GPS III Space Segment

The GPS III Space Segment program is a critical component of the Department of Defense's (DoD) space-based navigation infrastructure, managed by the United States Space Force and the Air Force. Its primary goal is to procure, deploy, and sustain the next generation of Global Positioning System (GPS) satellites, known as GPS III Space Vehicles (SVs). These satellites are designed to meet validated Joint Service requirements for worldwide, accurate, and reliable three-dimensional positioning, navigation, and timing (PNT) for military aircraft, ships, and ground personnel. The program supports both military and civilian users and is mandated to comply with Title 10 USC Sec. 2281 and 51 USC Sec. 50112, ensuring continued GPS operation and international cooperation.

The GPS III Space Segment program objectives focus on enhancing the resilience, accuracy, and security of the GPS constellation. The satellites broadcast high-precision data using synchronized signals, which are processed by user equipment installed on various military platforms. The control segment provides daily updates to maintain system precision, with a spherical error probable of 16 meters worldwide. The GPS III satellites also support the United States Nuclear Detonation Detection System and provide strategic and tactical support for joint operations, command and control, special operations, urban military operations, air mobility, and space launch support.

Specific procurement activities under the GPS III Space Segment include the production and deployment of SVs 07 through 10. These satellites deliver significant technical enhancements, such as the new international civil L1C Galileo-compatible signal and improved anti-jam capabilities. The program is currently in the Production and Deployment Phase for SVs 08-10, with launches scheduled for upcoming fiscal years. Funding supports launch services, mission assurance, crosslink capabilities, and operational milestones, ensuring that each satellite is successfully launched, declared operational, and integrated into the constellation.

For FY 2026, the budget line item justification details funding for independent technical and integration support, which is essential for managing SVs 07-10. This includes operational 365-day on-orbit incentive milestones, launch preparation events, and mission assurance activities for SV10. The funding also enables rapid response to implement system resiliency and situational awareness measures, allowing the program to operate effectively in contested space environments. These activities may leverage commercial partnerships, U.S. government collaboration, and international opportunities to address emerging threats.

The program's cost elements are divided into recurring costs for space vehicle production, technical mission analysis, enterprise systems engineering and integration (SE&I), launch services, on-orbit mission success incentives, and storage. Additional support costs cover Federally Funded Research and Development Centers (FFRDC), advisory and assistance services (A&AS), and other technical support necessary for program execution.

Each GPS III Space Segment budget line item is designed to ensure the continued modernization and sustainment of the GPS constellation. The program justifies its funding by emphasizing the need for enhanced anti-jam capabilities, international signal compatibility, and system resiliency in response to adversarial threats. The procurement and support activities are structured to maintain uninterrupted global PNT services for both military and civilian users, while meeting statutory requirements and facilitating international cooperation.