Air Force Set to ‘Significantly’ Change Launch Facilities for Sentinel ICBM

The design of the launch facilities for the Air Force’s new Sentinel intercontinental ballistic missile are likely to undergo major revision, posing yet another challenge for the much-delayed and over-budget program to modernize the land-based component of America’s nuclear triad, officials said May 6. 

“I imagine we’re significantly going to change it,” Acting Secretary of the Air Force Gary Ashworth told the House Appropriations Committee, referring to the strategy for the construction of the silos that will house the missile and the launch control facilities to operate it. 

Ashworth’s comments come on the heels of the Air Force’s determination that it will need to build new silos for Sentinel instead of relying on a previous plan to refurbish the roughly 450 existing Minuteman III silos.

The Sentinel program is being restructured—officials reviewed the effort after critical cost and schedule overruns triggered an inquiry under the Nunn-McCurdy Act. Then-Pentagon acquisition czar William LaPlante certified the program to continue, but rescinded its Milestone B approval and ordered a restructure.

Officials say Sentinel’s ballooning costs are not driven not by the missile itself, but by the massive work needed for the ground infrastructure. The latest revelations continue that trend.

“The missile itself will continue going through its design and development phase as we move forward,” Ashworth said. “The main contributors to the cost breach itself were the command and launch segment … it’s the construction costs associated with those elements that really drove up the cost.”

When Northrop Grumman won the Sentinel contract in 2020, the ground infrastructure was expected to be a significant civil engineering effort. But it is now proving more complex than anticipated, an Air Force spokesperson told Air & Space Forces Magazine.

“As the program continues to undergo restructuring activities, the Air Force analysis continues to confirm unacceptable risks to cost, schedule, and weapon system performance stemming from the original baseline strategy of converting Minuteman III (MMIII) silos,” the spokesperson said. “To mitigate this and other risks, the Air Force plans to build new missile silos on predominantly Air Force-owned real estate, which means reusing the existing missile sites but not the 55-year-old silos.”

Air Force officials are now looking at altering the acquisition strategy for the program. In February, the service suspended work Northrop’s work on the command and launch segment including the design of the launch facilities.

“The program right now is reaching out to industry to understand how we might better construct a program on how to get after that particular [command and launch] segment,” Ashworth said. “By the end of the summer, they should have collected enough information, analyzed it, and put it back together to see if we’re going to stay with the current acquisition strategy or significantly change it. I imagine we’re significantly going to change it based upon that strategy.”

The Air Force plans to field Sentinel as a one-for-one replacement for the 400 currently deployed Minuteman III missiles, which represent one of three legs of the U.S. nuclear triad.

The Air Force has ICBM wings at F.E. Warren Air Force Base, Wyo.; Malmstrom Air Force Base, Mont.; and Minot Air Force Base, N.D. Missile fields are spread out over five states—Colorado, Montana, Nebraska, North Dakota, and Wyoming.

“Part of the requirements, initially—10 years ago when this program was started—was to reuse the holes, the missile holes at the launch facilities. That was believed to be more efficient, more cost effective, and quicker,” Air Force Global Strike Command boss Gen. Thomas A. Bussiere said during remarks at ANWA Deterrence Center Forum on April 30. “Shockingly enough … that may not be the answer.”

An Air Force spokesperson confirmed reusing Minuteman III silos was no longer considered to be a viable option. 

“While no decision has been made, we expect Sentinel to use predominantly AF-owned real estate to build new missile silos instead of re-using MMIII silos,” the spokesperson said.

The Air Force has “data based on a test launch facility conversion project at Vandenberg Space Force Base that validated the implications of unknown site conditions with significant cost and schedule growth,” they added.

Breaking Defense first reported the Air Force’s change on building missile silos.

Air Force officials have recently said Minuteman III could be in service until 2050. The missile was originally expected to be decommissioned in the 2030s. 

Pentagon officials have argued the U.S. needs to embark on a costly but overdue modernization of all three legs of its nuclear triad, which also includes fielding the B-21 Raider bomber, upgrades to B-52 bomber, the Columbia-class submarine, and the Sentinel. The Air Force is also developing the Long Range Standoff Weapon (LRSO) and the E-4C Survivable Airborne Operations Center (SAOC) nuclear command and control aircraft.

Lawmakers are seeking to add $1.5 billion to Sentinel in a 2025 budget resolution and roughly half a billion dollars to keep Minuteman viable.

“These would be our priorities: this is going to be Sentinel, once it’s restructured, making sure that comes through,” Air Force Chief of Staff Gen. David W. Allvin told lawmakers. “… B-21, B-52, LRSO—those keep the nuclear deterrence.”