Sentinel work continuing; officials considering local impact
The Air Force’s Sentinel program is a behemoth with evolving details, but there’s been “forward aggressive progress.”
That’s what Peter Sturdivant has seen in the six months since being named director of intercontinental ballistic missile infrastructure for the Air Force Nuclear Weapons Center at Hill Air Force Base in Utah.
On April 1, Sturdivant and Lt. Col. John Mayer, the Sentinel site activation task force commander for Malmstrom, spoke with The Electric about the program’s progress.
Sturdivant said the missile components have been tested individually and a pad launch of the full missile is planned for 2027 at Vandenberg Space Force Base in California.
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The Sentinel program calls for 634 missiles, with 25 additional during the engineering and manufacturing development phase, according to the Air Force.
The bulk of work is still planned to start at F.E. Warren Air Force Base in Wyoming, then Malmstrom, followed by Minot, but some work is concurrent.
The Air Force, Northop Grumman and Bechtel, the contractors on Sentinel, broke ground in February on a full-scale silo prototype in Promontory, Utah that will be used to validate the “modular, cost-effective construction approach for 450 future silos that will support the modernization of the land-based leg of the nation’s nuclear triad. The data gathered will inform the final design and reduce risks before full-rate production,” according to the Air Force.
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The prototype is a “modular, repeatable construction approach designed to accelerate fielding, reduce cost growth and enable learning before full-rate production,” according to the Air Force.
Six additional prototyping activities will begin over the next few months focused on testing potential construction methods for the launch silos and the utility corridors, according to Air Force public affairs.
A pilot study is planned for this summer at F.E. Warren to test horizontal drilling as a method of utility installation, Sturdivant said.
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At Malmstrom, they’ll break ground on the $30 million new access gate, the first new Sentinel construction on base, this spring and summer. The gate will be the access point for the rest of the upcoming Sentinel construction on base.
Next year, Sentinel infrastructure work will begin on base, estimated at $212 million, for power, a new water tower and other utilities in an area of the base that didn’t previously need such infrastructure, followed by a new 180,000-square-foot consolidated maintenance facility.
Over the decades, the base has largely repurposed buildings designed for flying missions and Mayer said in February that this is the first time designing facilities specifically for the ICBM mission at Malmstrom, with about $1.2 billion in total Sentinel-related construction planned for Malmstrom.
The Malmstrom runway is no longer in use.
Environmental and cultural surveys are continuing in the missile field, particularly at former 564th Missile Squadron sites, which were deactivated as part of the New START Treaty and the last of which were demolished in 2014.
The 564th complex is northwest of Great Falls in Choteau, Pondera, Teton and Toole counties.
Mayer said they’re “walking every mile of the utility corridor,” across the Malmstrom missile field, to ensure utilities and the Hardened Intersite Cable System, or HICS, are where they think they are.
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The Malmstrom team is surveying for land acquisition with purchases to start next year and will be reaching out to landowners, Mayer said.
The launch sites in Malmstrom’s active missile complex are about two acres each.
Mayer said they’ll be looking to get those up to about five acres each for Sentinel. The sites in the 564th area are already large enough, he said.
New missile alert facilities will be about 10 acres each, Col. James Rodriguez said during the April 2 town hall.
He’s the Sentinel materiel leader-lower, launch systems at Hill AFB.
The Sentinel team will have maps during the April 2 town hall at 6 p.m. at West Elementary for landowners to see if they’re along those utility corridors.
The Air Force is hoping to use the former 564th area for Sentinel silos, but the decision has not yet been made and will be determined in part by the environmental surveys.
Using the 564th, and the deactivated 400th Missile Squadron sites, along with undeveloped land at F.E. Warren, would allow minimal interruption of the existing Minuteman III system’s operations, according to the Air Force.
Sturdivant said the initial operating capability for Sentinel is early 2030s at F.E. Warren.
He said there would likely be utility construction at Malmstrom by the early 2030s, but the system will not likely be operational here by then.
There are currently 450 silos across Malmstrom, F.E. Warren in Wyoming and Minot in North Dakota.
Of those, up to 400 have a deployed missile at any given time and the other 50 are in “warm status” a change made a decade ago to meet requirements in an arms reduction treaty with Russia. That treaty, New START, expired in February.
New START limited the number of deployed and non-deployed nuclear weapons and the number of warheads on deployed weapons.
Under New START, deployed Minuteman III ICBMs have been armed with a single re-entry vehicles, which carry the warhead, though they were capable of carrying more.
In March, the Air Force conducted an ICBM test launch with two re-entry vehicles.
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While the Air Force has conducted tests with multiple reentry vehicles in recent years, March’s test was the first since the expiration of New START.
In a statement, the Air Force said that the “Sentinel missile will have the ability to carry multiple reentry vehicles. Any decision to deploy that capability will be made by the President based on the strategic needs of the nation.”
The Sentinel maintains 450 silos, with 150 at each wing, Mayer said.
Currently, each of the three missile squadrons at Malmstrom operates 50 silos each.
If the 564th is approved for Sentinel, 55 silos may be built in that area, and the Air Force may choose a different configuration across the missile field, removing sites from other areas to maintain the balance, Mayer said.
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Factors in that decision include drive times, since some sites to the east are more than three hours away; shifting water tables are causing continuous leaks at existing sites; known underground corrosion issues at some current sites; and all-weather access, Mayer said.
Some sites in the Little Belts are difficult to access in the winter and airmen have to helicopter in or remain on site longer, Mayer said, so some configuration changes may be made to optimize Sentinel deployment.
Each missile wing will have eight launch control centers in the missile field, down from the current 15.
Those LCCs may have more personnel than Minuteman III sites because fewer are across the missile field, Mayer said.
Sentinel will also have a command and control center on base, a change from Minuteman III, he said.
The current system is three individual, isolated networks at each wing.
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With Sentinel, it will be wing-wide, so everyone across the missile field can see and operate the system, making it more efficient, Mayer said.
With greater connectivity for Sentinel comes the question of cybersecurity, which Sturdivant said is “at the forefront of every consideration for the protection of the system. It could be a real hazard, but this really will be a state-of-the-art system with cyber security.”
In preparing local communities for Sentinel, Sturdivant said the Air Force and contractors heard local concerns about road conditions and the impact of construction vehicles. The Air Force also needs roads for its own operations and coordinates with localities to help fund the cost of missile roads.
He said Northrop Grumman initiated road studies across all three wings and contractors will be responsible for maintaining roads and returning them to their pre-construction condition.
Tim Barlow, the roads and bridges coordinator for Sentinel, said during the April 2 work session that the contractor will provide the roads and bridges assessment for the Air Force to evaluate if it needs to modify roads or replace bridges for the construction work.
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Mayer said that last summer, Northrop and Bechtel took snapshots in time of road conditions across the missile fields for road assessments and will take more snapshots throughout the project.
Mayer said he’s working with the local Montana Department of Transportation office and is involved in that agency’s Central Montana traffic study.
He said the Sentinel team is aware of bridge heights and weights as well as limitations on roads.
The existing transporter erector carries about 80,000 pounds of missile, which are known conditions, and Mayer said the team is aware of the road impact of any changes to that equation.
The workforce hub concept is a detail that’s in flux and still being evaluated.
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Sturdivant said that they don’t yet know the delivery method for silos and missiles, which could come in batches of 10 or 20, or something entirely different.
“We’re also trying to figure out how big of a workforce we need for construction,” Sturdivant said, something the silo prototype in Utah will help determine.
Decisions about the workforce hubs haven’t yet been made, he said, but there will be a huge need for skilled labor.
Mayer said the workforce hub concept has changed from the initial plan of locating them in Great Falls and Lewistown.
“It’s complicated,” he said, and the Sentinel team is still assessing that plan.
The number of contractors working on the project isn’t expected to exceed 3,000, according to the Air Force’s updated fact sheet and most would be housed at the workforce hubs in the vicinity of construction.
During the April 2 town hall, Sturdivant said they’re estimating about 1,000 contractors per base.
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Cascade County is currently hiring for a federal grant-funded Sentinel liaison position, and Mayer said he foresees that position being heavily involved in the workforce hub planning.
Based on current projections, Sentinel work requiring a workforce increase at F.E. Warren will begin in 2027 and be completed in the mid-2030s, with work in Montana and North Dakota starting after 2027, according to the Air Force’s fact sheet.
As Minuteman III comes off alert, the silos will follow their standard demilitarization process, Rodriguez said, and the missiles may be used in the testing program as long as Minuteman III is operational or be disposed of.
The current HICS lines will be abandoned in place since they have to stay operational as Sentinel lines are installed, he said.
Mayer said that if locals have questions about Sentinel, they can call or email and staff will work to get an answer, though it may take time depending on how complicated the question is.
Sentinel email is AFGSC.Sentinel.Hotline@us.af.mil and the Malmstrom Sentinel hotline is 406-731-2427.
