The U.S. Air Force and Northrop Grumman have vertically assembled an inert LGM-35A Sentinel intercontinental ballistic missile at Vandenberg Space Force Base in California in a Pathfinder integration test. The demonstration verified that key subsystems are on track for initial flight testing in 2027 and highlighted progress on the programme intended to replace the Minuteman III fleet.
The missile was stacked in its operational orientation after a four-month campaign that validated transport, crane-lift, interface-check and field-assembly procedures. The service also completed a flight-test design review alongside the on-pad integration work, confirming the design’s maturity for the next phase of development.
Sentinel remains part of the U.S. ground-based nuclear deterrent modernisation effort, with initial operational capability still targeted for the early 2030s. The Pathfinder event provides the first full vertical representation of the new missile and supports preparations for the planned flight-test programme at Vandenberg.