The Air Force insists it is standing by its ambitious plan to replace all 450 of its Cold War-era Minuteman III missiles with the LGM-35A Sentinel intercontinental ballistic missile, despite massive cost overruns that breached expected guidelines by such a huge margin last month that they triggered an official notification to Congress.

In 2020, the Sentinel program’s cost was $118 million per missile. The price rocketed to $162 million within three years, a 37% increase. The missiles were supposed to be fielded by mid-2030, but now officials expect at least a two-year delay before the program is ready.

The severe cost inflation triggered what is known as the “Nunn-McCurdy breach” mandating that Congress be officially informed that the price tag was rising. The 37% overrun puts the program in “critical” status under the law’s guidelines, a status that had traditionally been the last step before outright termination — unless the Pentagon certifies there is no alternative to keeping the program alive.

“The Office of the Secretary of Defense will conduct a review of the Sentinel program to decide whether to terminate or restructure the program,” the Air Force said in a statement to The Washington Times, but it is widely expected the troubled program will be given a stay of execution.

The latest cost figures come after a critical Government Accountability Office report last summer that detailed numerous delays facing sole contractor Northrup Grumman, including staffing shortfalls, clearance delays, IT infrastructure challenges and supply chain disruptions.

The stakes are high and the logistics are daunting for one of the U.S. nuclear force’s very top priorities. Just managing the scale of the construction of a replacement generation of missiles involves real estate rights and construction facilities, a major new infrastructure to oversee the deployment and operation of the missile, and the manufacturing challenges that come with building a new-model ICBM.

“Sentinel is one of the most large, complex programs I’ve ever seen,” Air Force Secretary Frank Kendall told a think tank briefing in November, according to an account in Defense News. “It’s probably the biggest thing, in some ways, that the Air Force has ever taken on.”

All work under the current Sentinel missile contract will continue until Mr. Austin’s office completes that review. “Maintaining a strong nuclear deterrent is critical to safeguarding our nation and protecting our allies from a nuclear attack,” the Air Force said.

Northrop Grumman is the prime contractor for the engineering and manufacturing phase of the Sentinel program. In a statement to The Times, the Virginia-based aerospace and defense giant said it’s making “significant progress” on the complex program and is achieving key milestones.

“Our team is committed to supporting the Air Force as it assesses and updates acquisition cost forecasts for the future phases of the program, to include construction projects, production and deployment of the weapon system,” the company said. “We are continuing to perform and meet our commitments under the [engineering and manufacturing development] contract as we move toward delivery of this essential national security capability.”

House Armed Services Committee Chairman Mike Rogers, Alabama Republican, said he is committed to vigorous oversight of the Sentinel program and ensuring that the Air Force makes the necessary changes to address cost overruns while continuing to advance the program.

“Sentinel is absolutely necessary for the future of our nuclear deterrent,” Mr. Rogers said. The Defense Department “must ensure that Sentinel is ready in time to replace the current ICBMs before they reach the end of their lives. Failure is not an option.”

Construction project

Ground-launched missiles are one leg of America’s nuclear triad, along with submarines and the Air Force’s fleet of nuclear-capable combat aircraft such as the B-52 bomber, which has been flying since the 1950s.

But the missiles themselves are only one part of the Sentinel program. It also requires a massive new infrastructure framework to support the system. The Air Force has called it their largest military construction project, spanning more than seven military installations.

Speaking at the Center for Strategic and International Studies on Jan. 24, Undersecretary of the Air Force Kristyn Jones said the missile itself is not their biggest concern about the viability of the Sentinel program.

“A large part of it is essentially a civil works program,” Ms. Jones said. “Those are areas that traditionally in government have been challenging — especially in the last couple of years given the macroeconomic environment, the labor force, military construction [and] supply chains. Those kinds of things are contributing to some of the challenges that we’re seeing.”

As part of the review mandated by the Nunn-McCurdy breach, the Pentagon will look for opportunities to reduce the cost of the Sentinel program along with retooling the management structure, Ms. Jones said.

“We already have some ideas that we’re working on to see how we can source that,” she said.

Sentinel’s large program scope — developing new technologies, modifying existing systems, and constructing new infrastructure, along with its size add to its overwhelming complexity, the GAO’s June 2023 report to Congress noted.

“Sentinel is behind schedule due to staffing shortfalls, delays with clearance processing, and classified information technology infrastructure challenges,” the GAO said. “Additionally, the program is experiencing supply chain disruptions, leading to further schedule delays.”

Squeezing a few more years out of the aged Minutemen III family of missiles will not solve the problems with cost overruns from the Sentinel program, said Lt. Gen. Richard Moore, the Air Force’s deputy chief of staff for plans and programs.

“There is not a viable service life-extension program that we can foresee for Minuteman III. It was fielded in the 1970s as a 10-year weapon,” Gen. Moore said during the recent CSIS forum. But, “we will do everything we can to keep it in the field.”

Ms. Jones said nuclear modernization is key to the nation’s defense and most members of Congress would likely agree.

“We believe very strongly that our nuclear modernization will continue,” she said. “We just need to make some changes into how we’re operating the program.”

• Mike Glenn can be reached at mglenn@washingtontimes.com.