ARLINGTON, VA – The U.S. Air Force is considering modular missile silos to house the service’s future LGM-35A Sentinel intercontinental ballistic missile (ICBM) by Northrop Grumman, while using the same locations as the previous siloes.
“My understanding is they [the Air Force] will largely use the same locations,” Sen. Kevin Cramer (R-N.D.) told reporters Wednesday after he gave the opening keynote on the final day of Exchange Monitor’s Nuclear Deterrence Summit. “It’s amazing how much room there is on the other side of those [base] fences.”
Cramer is a member of the Senate Armed Services Strategic Forces Subcommittee. North Dakota is home to the 91st Wing at Minot Air Force Base (AFB), which houses siloes for the Boeing LGM-30G Minuteman III, the nation’s current intercontinental ballistic missile (ICBM) until Sentinel replaces it next decade.
Cramer said the Air Force is “pretty well settled” on new silos, but he had favored reusing the Minuteman silos for Sentinel and said “it sort of irritated me that somebody didn’t design better earlier, but I sort of resigned myself to that [new silos].”
“It irritated me a lot, but they designed a missile that’s bigger–what can you say,” Cramer added. “I do think that just the difference that modernization brings and the efficiencies of things, it probably makes sense anyway to have a brand new home for each one of them [Sentinels].”
Modular silos would use pre-cast concrete and standardized components to reduce construction cost and time, but the approach may also mean less silo hardening and present logistical challenges in transporting the large modules. These would be dropped into place at existing sites under the 90th Wing at F.E. Warren AFB, Wyo., the 91st Wing at Minot AFB, N.D., and the 341st Missile Wing at Malmstrom AFB, Mont.
The 90th is to be the first to receive Sentinel, followed by the 341st, and, finally, the 91st, Sen. John Hoeven (R-N.D.) told the Monitor in September. Cramer confirmed in his speech Wednesday that Minot would be the final wing.
The Sentinel silos are to be new rather than refurbished Minuteman silos as the Air Force had planned earlier. That’s in part because of the larger Sentinel, but also because of environmental conditions in the silos for the current Minuteman III, including asbestos, lead paint, and tilting in a small number of silos due to variations in their concrete thickness.
Exchange Monitor affiliate Defense Daily first published a version of this article.