About Sentinel (GBSD)

About Sentinel (GBSD)

The U.S. Air Force’s LGM-35A Sentinel weapon system, formerly known as the Ground Based Strategic Deterrent (GBSD), is a critical modernization of the ground-based leg of the U.S. nuclear triad, the bedrock of U.S. national security. The Sentinel (GBSD) system replaces the aging Minuteman III intercontinental ballistic missile (ICBM) system, which has been in service for over 50 years.

As the Sentinel (GBSD) prime contractor, Northrop Grumman is producing a modern, integrated system designed to be adaptable to meet future threats and keep pace with emerging technologies. A cornerstone capability of the triad, the system will support global stability by serving as a safe, secure and credible deterrent that will protect our nation and assure allies for decades to come.

Reducing Risk through Digital Engineering

The Sentinel (GBSD) system is the Air Force’s first major acquisition program to earn the e-Programs designator. This revolutionary approach for what the government defines as a “mega project” leverages digital engineering, agile software, and open systems architecture to model and authenticate virtual designs, lowering risk and reducing the time it takes to field the system and new technologies.

Future Strategic Deterrence

For the first time in history, the U.S. is facing two near-peer adversaries who are rapidly expanding and modernizing their nuclear weapons. Recognizing the need to maintain a credible deterrent amidst an evolving global security environment, the U.S. is modernizing each leg of the triad.

Minuteman III has served as the ground-based leg of the triad since the 1970s and is the oldest deployed strategic ballistic missile in the world. It has undergone three service-life extension programs to ensure safety and reliability, but major components are aging out, including boosters and guidance systems.