GROUND BASED STRATEGIC DETERRENT (GBSD)
The GBSD program has been designated as the LGM-35A Sentinel. The LGM-35A Sentinel weapon system, being developed in the Sentinel Systems Program Office of the ICBM Systems Directorate, incorporates the Sentinel weapon system which is called out in related ICBM Systems Directorate portfolio programs that includes Intercontinental Ballistic Missile (ICBM) Reentry Vehicles and ICBM Fuze Modernization. The LGM-35A Sentinel program is modernizing the U.S. ground-based nuclear deterrent by replacing the aging Minuteman III ICBM system. The Sentinel program will develop, produce, and deploy a fully integrated ICBM weapon system designed for enhanced safety, security, reliability, and effectiveness. This next-generation system aims to lower lifecycle costs while closing key capability gaps and addressing vulnerabilities identified in prior assessments. The program also mitigates the diminishing effectiveness of the current land-based deterrent caused by the age and obsolescence of Minuteman III components. Integrated with the Minuteman III program office within the ICBM Systems Directorate, the Sentinel program will manage the complex transition between systems. This includes overseeing contractor development of essential support equipment, data systems, flight test infrastructure, and training systems. Throughout this process, the program prioritizes risk mitigation and ensures adherence to strict nuclear surety, certification, and vulnerability assessment protocols. Key technical areas include: Flight Systems (missile boosters, re-entry vehicle, and guidance systems); Command & Launch (secure and reliable communication and control systems); Infrastructure & Deployment (training, maintenance, and launch infrastructure; fielding and system deployment); Software (robust and resilient weapon system software ecosystem); Systems Engineering (overall system design, cybersecurity, and modular architectures); and Test (developmental, operational, and live fire testing for safety and effectiveness). Effective program management will leverage digital engineering capabilities, oversee program execution, and manage major contracts. The FY 2027 funding will continue execution of the prime contract and advance key Sentinel program activities.
Continue to implement updated specifications, execute design reviews, and mature critical components like AVE, support systems, specialized support equipment, cybersecurity, and nuclear surety architectures. Continue to refine the Mission Modeling Framework to assess performance against evolving threats. Continue to mature the weapon…
Read the FY2027 plan →Continue to prioritize the development of robust C&L systems. This includes ongoing refinement of command-and-control mission equipment, the wing command center, and crucial cryptographic systems and interfaces. Develop communications systems (hardware and software), air and ground hardware, and control equipment to ensure the…
Read the FY2027 plan →Continue to develop and modernize infrastructure to support the weapon system's lifecycle. This includes the construction of utility corridors, overseeing real estate acquisition, and pursuing paths for launch silo design and construction to inform acquisition strategies. Continue to establish standard designs for launch silos and launch…
Read the FY2027 plan →Continue to mature the weapon system's software technology, ensuring robust cybersecurity, and developing comprehensive software sustainment strategies. Continue to refine requirements and modular architectures through rigorous testing and analysis, as well as maturing weapon system software, integration, and lifecycle management…
Read the FY2027 plan →Continue to mature Sentinel specifications, architecture, and design through rigorous systems engineering to include modular architectures, external interface management, modeling and simulation, and testing to ensure the appropriate level of maturity required for each technical review. Continue to collaborate with mission partners to…
Read the FY2027 plan →Increase efforts to develop, modernize, and expand test capabilities for the weapon system across all stages of testing, including technical maturity, developmental, operational, and live fire test and evaluation. The emphasis is on identifying and filling capability gaps, particularly for development of a host site and logistics for the…
Read the FY2027 plan →Continue to ensure the program has the necessary manpower, technical expertise, management, physical security, IT infrastructure, and cybersecurity capabilities to successfully develop and acquire the weapon system. Continue to manage and acquire support from various program partners such as Federally Funded Research and Development…
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