A Once-in-a-Generation Evolution
By Presley Price
Recognizing the need to maintain a credible deterrent amidst an evolving global security environment, the U.S. is modernizing each leg of the Nuclear Triad.
The U.S. Air Force’s Sentinel LGM-35A weapon system is a critical modernization of the ground-based leg of the U.S. Nuclear Triad. Historic in scope and complexity, Sentinel is more than a missile. This once-in-a-generation system evolution includes designing and producing more than 450 new missiles, a vast nuclear command and control network and hundreds of infrastructure projects including hardened silos spread across thousands of miles in five states.
Sentinel is one of the most complex programs the U.S. Air Force has undertaken, and Northrop Grumman is at the forefront of the industry team driving progress to deliver the most technologically advanced intercontinental ballistic missile (ICBM) system to stay on alert through 2075. Significant progress has been made in developing and testing the missile, fortifying the supply chain and maturing the infrastructure design and construction approach.
From Below the Ground Up
While it has served the nation well, the Minuteman III ICBM was initially designed in the 1960s, deployed in the 1970s, and meant to be retired and replaced after a decade. While refurbishing the original 450 missile silos presented significant cost and schedule constraints, designing and building new silos provides an opportunity to explore more efficient design concepts, achieve predictable cost estimates, consider parallel construction efforts and optimize Sentinel deployment.
In 2024, Northrop Grumman deeply examined the full scope of the Sentinel program and developed 10 alternative launch silo design options analyzed across 32 fielding scenarios including workforce capacity, supply chain, geographical limitations, means and methods of construction, sequencing of key events and more. Working in close partnership, the U.S. Air Force and Northrop Grumman identified the design concept selected as the basis for recertification of the program, projected to significantly decrease fielding time and acquisition costs compared to projected estimates for using the original silos. While the new launch silos are constructed, Minuteman III missiles will stay on alert as a viable deterrent to ensure a seamless transition to this next-generation capability.
Design decisions matter – especially when it comes to the bedrock of U.S. national security. Northrop Grumman is designing the entire weapon system from below the ground up with innovation at its core.A Generational Leap
Full ICBM modernization hasn’t been tackled in more than 60 years, but Northrop Grumman is known for tackling the nation’s toughest challenges. Working jointly with the Air Force and a nationwide team of suppliers, the company is investing in the industrial base, maturing the design and reducing risk on the path to make Sentinel a reality.
Once fielded, Sentinel will bring game changing capabilities including improved range, accuracy, resiliency and flexibility. Sentinel is a modular system that can be adapted and move at the pace of technology to stay ahead of the threat. Grounded in digital engineering, Northrop Grumman is transforming the way the system is being designed and produced. The result: enhanced performance, faster, more accurate decision-making for the warfighter and enduring deterrence that will protect generations to come.