The US Air Force, in partnership with Northrop Grumman, is aiming for a 2027 first flight of the LGM-35A Sentinel ICBM, marking a major step toward replacing the legacy Minuteman III. The system is expected to achieve initial operational capability in the early 2030s.
Sentinel is intended to modernize the land-based component of the US nuclear triad, transitioning from a missile system that has been in service since the Cold War era. The program covers an operational footprint of around 32,000 square miles and includes upgraded silos, command-and-control systems, and transport infrastructure alongside the missile itself.
The development strategy follows a phased acquisition model, enabling early-stage testing and continuous refinement. This method allows design updates to be integrated during development, helping mitigate risks and streamline timelines.
The program has advanced from digital modeling to prototype and hardware testing. All major propulsion elements have been validated through prototype testing, and a three-stage booster has been assembled to confirm design and production processes. Solid rocket motors for future flight tests are already being manufactured.
Testing activities have included interstage separation trials and payload shroud validation, as well as rigorous evaluation of guidance and control systems through sled-based simulations that replicate flight stresses.
Supporting infrastructure development is progressing in parallel, including a modular launch silo concept designed to replace or supplement existing Minuteman III facilities. Transport systems have undergone long-distance trials to ensure secure and reliable movement of missile components.
Additionally, a digital launch support system has completed its critical design phase and is transitioning into build and testing. The Sentinel program encompasses over 500 suppliers and a workforce of more than 10,000, with the missile expected to remain in service through at least 2075.
