Modernizing the Nation's Ground Based Strategic Deterrent: The Sentinel Missile

For more than six decades, a safe, secure, and effective strategic deterrent has served as the bedrock of United States national security. To keep pace with the emerging threat environment, the U.S. is spearheading a critical modernization of the current land-based leg of the strategic triad, known as Sentinel.  

This next-generation Sentinel system replaces the Minuteman III, which has been in service for more than 50 years. Delivering on this capability is a Northrop Grumman-led team producing the most technologically advanced portion of this new ground-based strategic deterrent, designed to be viable through 2075.

Making it possible - Digital engineering and advanced manufacturing 

The Sentinel program represents advancements in technology with the use of digital engineering, advanced tooling, and a modular, open-architecture approach, helping to ensure the Northrop Grumman team develops this next-generation capability with innovation at its core. 

Critical partnership

During the design phase, known as engineering, manufacturing and development, Northrop Grumman and its U.S. Air Force partner are executing a rigorous test campaign stressing several crucial elements of the Sentinel LGM 35A missile design. 

Delivering on our commitments

“Working with the Air Force and our team of suppliers, we have put key elements of the missile’s hardware to the test to mature our design and lower risk. These successes give us confidence as we continue progressing on the path to deliver this essential capability to the nation,” said Sarah Willoughby, vice president and program manager, Sentinel, Northrop Grumman.

Steady progress

The Sentinel missile features a three-stage booster, with Northrop Grumman producing stages one and two. The booster is a new design, using the latest materials and design technologies to ultimately improve performance, reliability, safety, and sustainability. 

The Northrop Grumman team has successfully test fired all three stages of the Sentinel booster. Added Willoughby, “We have successfully demonstrated the propulsive performance of each motor in the booster stack. As we continue to mature missile design and transition from development to qualification testing the merits of digital engineering have underpinned our success, allowing our team to efficiently mature propulsion designs as we progress toward delivering this essential national security capability.”

The Northrop Grumman team’s test campaign also included a successful shroud fly-off test at Naval Air Weapons Station China Lake. This proved that digital modeling predictions are solid as the test verified the shroud, which protects the missile’s payload in flight, did not strike the enclosed payload.

At the company’s Strategic Missile Test and Production Complex in Promontory, Utah, the team performed a stack test to evaluate the forward and aft sections of the missile. The team gleaned important data about inflight structural dynamics that continue to help engineers validate assumptions and fine-tune models ahead of further demonstrations and tests.

Leading up to these successes were a series of rigorous wind tunnel tests of scaled models of the vehicle, stressed under environments from sub to hypersonic speeds, that validated digital modeling and simulations and proved design maturity.

Looking ahead

As the Northrop Grumman team advances towards Critical Design Review, the team continues to enhance certainty in the maturity of the Sentinel missile design and lower risk through innovation enabled by digital tools and advanced manufacturing techniques. Northrop Grumman, together with its nationwide team, is focused on performance, making progress against milestones to deliver on Sentinel priorities. In conjunction with the Air Force, the Sentinel team is maturing the design, reducing risk, and meeting a commitment to deliver a safe, secure and credible deterrent capability to protect the United States and assure allies for decades.