Fully integrated 6,000-mile Sentinel missile assembled vertically for the first time

The U.S. Air Force and Northrop Grumman have assembled a full-scale Sentinel missile configuration ahead of its planned 2027 flight test. Engineers stacked the inert missile at Vandenberg Space Force Base in California during a four-month ground test. The exercise gave the team a chance to rehearse the demanding procedures needed before a live launch. The milestone marks an important transition for Sentinel. Engineers are now testing how the weapon system comes together outside the design environment. Engineers rehearse missile assembly The exercise, known as Pathfinder, focused on the practical challenges of handling the new ICBM. Teams moved missile components from facilities across the United States to Vandenberg. They used specialized transport vehicles and mobile cranes during the operation. Engineers then brought the components together in the missile’s operational orientation. They checked the interfaces connecting the major sections before completing the stack. The team later de-stacked the inert missile after completing the ground exercise. That process gave engineers another opportunity to verify their procedures. Pathfinder therefore tested more than the hardware itself. It also examined whether crews could execute the required procedures safely on a launch pad. Sentinel requires precise coordination during assembly. A mistake in transportation or integration could create problems during later testing. The exercise also allowed engineers to work through the logistics surrounding a complete missile configuration. Those procedures will matter when the program moves toward increasingly demanding flight operations. Design review clears next step Northrop Grumman also completed a major review with the Air Force’s 719th Test Squadron. The first flight-test Critical Design Review examined the missile’s design maturity. Engineers also assessed hardware testing against Air Force requirements. The review covered performance, safety, and schedule requirements for the planned 2027 flight test. Its completion gives the program another technical checkpoint before flight operations begin. That review adds another layer of confidence before Sentinel leaves the ground. Flight testing will expose the system to conditions that ground exercises cannot fully reproduce. Amanda Davis, Northrop Grumman’s vice president for strategic deterrent systems, linked the assembly milestone directly to the upcoming test. “This vertical assembly demonstrates the momentum toward test launching Sentinel in 2027,” Davis said. She added that the program aims to place missiles on alert during the early 2030s. Sentinel targets decades-long service Sentinel forms the planned replacement for America’s aging Minuteman III ICBM force. The Air Force lists the LGM-35A Sentinel with a range of more than 6,000 miles, giving it intercontinental reach. The Air Force considers the program a modernization of the ground-based portion of its nuclear triad. Northrop Grumman leads more than 500 industry partners on the effort. The broader Sentinel workforce now exceeds 10,000 people across the country. Engineers are also working on infrastructure, missile testing and production readiness. The program aims to produce an ICBM system capable of remaining viable through 2075. That timeline places heavy demands on the weapon’s design and supporting infrastructure. The 2027 flight test will provide a much tougher test of those preparations. Sentinel must move from controlled ground demonstrations to actual flight operations.Get the latest in engineering, tech, space & science - delivered daily to your inbox.Aamir is a seasoned tech journalist with experience at Exhibit Magazine, Republic World, and PR Newswire. With a deep love for all things tech and science, he has spent years decoding the latest innovations and exploring how they shape industries, lifestyles, and the future of humanity.