Air Force authorizes start of construction on Sentinel support facilities

June 2, 2023
By Exchange Monitor

Robert Moriarty, the Deputy Assistant Secretary of the U.S. Air Force for Installations, authorized the support construction phase for the Northrop Grumman’s LGM-35A Sentinel missile.

The Department of the Air Force’s 450 missile silos, launch facilities and 45 missile alert facilities “would be updated extensively to completely refurbished condition to meet the requirements of the Sentinel system,” according to a May 19th final Environmental Impact Statement Record of Decision signed by Moriarty.

“Sentinel system deployment and MMIII [Minuteman III] disposal activities are scheduled to sequentially begin in late 2023,” the document reads. Main Operating Base (MOB)-1 at F.E. Warren Air Force Base in Wyoming will be first, followed by MOB-2 at Malmstrom Air Force Base in Montana, then MOB-3 at Minot Air Force Base in North Dakota, the Air Force said.

Building of the installation command center and the material handling complex at F.E. Warren is to begin this year. Construction is to start at Malmstrom in 2026 and at Minot in 2029.

The Air Force’s Record of Decision said that F.E. Warren is to be the first MOB because it “has the best local industrial capacity because of its proximity to Denver, the ICBM [intercontinental ballistic missile] Program Office and depot at Hill [Air Force Base], two major interstate highways, a railway hub, and a major airport that would be used for movement of supplies, equipment, and personnel.”

Under what it calls the “Reduced Utility Corridors Alternative” the Air Force plans to build 2,500 miles of new utility corridors, or 626 fewer than the originally proposed 3,126 miles of corridors. The service also now plans to reuse “marginally fewer miles of existing utility corridors” than the original proposal, according to the Record of Decision.

Air Force Secretary Frank Kendall told the House Armed Services Committee in April that it will be a challenge for Sentinel to reach initial operational capability by the target date of 2029. Kendall is not permitted to make decisions about Sentinel because of his previous consulting work for Northrop Grumman.

A Defense Department report sent to Congress in September indicated a possible 10-month delay in the estimated $95.8 billion Sentinel development effort. In February, Air Force Brig. Gen. Ty Neuman, the service’s director of concepts, said Northrop Grumman is still on track to perform a full-scale inaugural flight test this year.

Sentinel will be a three-stage, solid-fueled booster rocket with first and second stages supplied by prime Northrop Grumman, which has an in-house solid rocket motor business in the assets of the former Orbital-ATK.

Aerojet Rocketdyne, the sole remaining independent provider of solid rock motors in the U.S., will make the third-stage motor.

Sentinel will initially carry the W87-0 thermonuclear warhead, refurbished versions of the W87 warhead from the Minuteman III missiles it will replace. Later Sentinels will be tipped with the W87-1 warhead, a newly manufactured copy of the Minuteman’s W78 warhead, but with a fresh plutonium pit.

The National Nuclear Security Administration’s Lawrence Livermore National Laboratory will provide both warheads. The Los Alamos National Laboratory will provide the new pits.