US Air Force Considers Extending Life of 1970s ICBMs Amid Sentinel Delays

The US Air Force is exploring contingency plans to extend the service life of its aging Minuteman III intercontinental ballistic missiles (ICBMs) by an additional 11 years, until 2050, due to ongoing delays with the next-generation Sentinel missile program, Bloomberg reports.

The Air Force’s current plan calls for the removal of all 400 Boeing Co.-manufactured Minuteman III ICBMs from their silos by 2039. This involves a complex process managed by the Air Force and lead contractor Northrop Grumman Corp., entailing the removal of the older missiles, refurbishment of the silos, and the subsequent installation of the new Sentinel ICBMs. This delicate operation must be completed without compromising the nation’s nuclear deterrent.

The Sentinel program has faced significant setbacks. Initially projected for deployment starting in May 2029, the first test flight, once slated for December 2023, has now been pushed back to February 2026, according to fiscal 2025 budget documents.

Adding to the complexity, the Air Force and Pentagon acquisition officials are currently reviewing the implications of a projected 81% cost increase for the Sentinel program, which now estimates a total cost of at least $141 billion.

The Sentinel is a crucial component of the US nuclear triad, representing the land-based leg. Its modernization is considered vital to bolstering the lethality of the American nuclear arsenal, as advocated by Defense Secretary Pete Hegseth.

The program is currently overseen by the Pentagon’s under secretary for acquisition. President Donald Trump’s nominee for that position, Michael Duffey, is scheduled to appear before the Senate Armed Services Committee Thursday for a confirmation hearing, where the Sentinel’s rising costs and delays are likely to be discussed.

The Air Force indicated that it is actively developing an updated acquisition strategy for the Sentinel program.

“Further details will be available after the updated strategy is approved, which is currently expected in 2026,” the Air Force said. “The Air Force will not have a new timeline and phasing for transition” from the Minuteman III to Sentinel “until the program is restructured.”

Last month, the Air Force’s “Integrated Product Team,” responsible for overseeing the Minuteman III, convened at Hill Air Force Base in Utah to discuss sustainment options. During the “Secret” meetings, the team evaluated “End of Life 2050” issues, including battery life and testing strategies, according to an agenda obtained by Bloomberg News.

The Air Force clarified that the meeting was not intended to set end-of-life dates for the Minuteman III but rather to communicate risks and mitigation strategies for its continued operation until the Sentinel is deployed. The program office tracks over 1,600 elements, communicating “risks and mitigation strategies to the Air Force for continued sustainment” of Minuteman III.

Northrop Grumman struck a positive note in their statement:

“We continue to make substantial progress on the Sentinel Weapon System, including the missile.”