Sentinel ICBM

The U.S. Air Force is replacing the aging LGM-30 Minuteman III intercontinental ballistic missile (ICBM) with the LGM-35A Sentinel ICBM. The Sentinel ICBM represents the modernization of the land-based leg of the U.S. nuclear triad.

Note: The LGM-35A Sentinel was originally called the Ground Based Strategic Deterrent, or GBSD, in the early stages of its development.

Nuclear deterrence is the No. 1 priority mission of the Department of Defense. The nuclear deterrent underwrites every U.S. military operation on the globe—it is the backstop and foundation of our national defense and that of our allies.
 
The Air Force Nuclear Weapons Center’s mission encompasses the entire lifecycle management of the Air Force’s nuclear weapon systems—acquisition, sustainment, modernization and, ultimately, disposal and demilitarization. 
 
AFNWC's ICBM Systems Directorate is working to replace the aging Minuteman III, the most responsive leg of the triad, with the new Sentinel ICBM. Although certain components and subsystems have been upgraded since the Minuteman III ICBM system first became operational in the early 1970s, most of the system’s fundamental infrastructure still uses the original equipment.
 
The Sentinel ICBMs will replace the 400 Minuteman III ICBMs currently in service for more than 50 years in Air Force missile fields at F.E. Warren Air Force Base (AFB), Wyoming; Malmstrom AFB, Montana; and Minot AFB, North Dakota.
 
Some Sentinel maintenance, training, storage, testing and support actions will occur also at Hill AFB, Utah; Utah Test and Training Range, Utah; Camp Guernsey, Wyoming; and Camp Navajo, Arizona.
 
Existing launch facilities, missile alert facilities, communication systems, infrastructure, and technologies for the Minuteman III ICBM will be modernized and replaced as necessary to support the new Sentinel weapon system.  The Minuteman III ICBMs will be decommissioned, which requires demilitarization and disposal activities.
 
The Sentinel development and deployment will not include generating or disposing of nuclear material and the total number of land-based nuclear missiles on alert 24/7/365 in the continental United States will remain the same.