The U.S. Air Force and two essential contractors on the LGM-35A Sentinel intercontinental ballistic missile program on Saturday tested the solid-rocket motor that may power the nuclear weapon’s third stage.
The test, which also involved Northrop Grumman and Aerojet Rocketdyne, took place in a closed chamber on the Arnold Engineering Development Complex in Tennessee. It followed static fire tests of the primary and second stages’ rocket motors in March 2023 and January 2024, respectively.
This third stage that was tested is the smallest of Sentinel’s three-stage propulsion system. The Air Force didn’t offer further details in regards to the test, nor did it discover whether the event was successful.
“This test is the most recent in our ground and flight test program and is designed to assist us refine Sentinel’s air vehicle design,” Maj. Gen. John Newberry, commander of the Air Force Nuclear Weapons Center and the service’s program executive officer for strategic systems. “It demonstrates the progress the Air Force is making on modernizing our nation’s strategic land-based nuclear deterrent.”
The Sentinel program is meant to interchange the aging LGM-30G Minuteman III ICBM, which has been a key a part of the US’ nuclear triad for the reason that Cold War. The Air Force now has roughly 400 Minuteman III weapons in silos unfolded across Wyoming, Montana, North Dakota, Colorado and Nebraska.
Northrop Grumman didn’t issue a news release in regards to the test, but provided a brief statement to Defense News: “In partnership with the Air Force, we proceed to make significant progress on the Sentinel program, achieving key milestones to mature the design and reduce risk.”
Northrop said in a February release it had successfully tested several other elements of the missile. This included evaluating the forward and aft sections of a Sentinel ICBM at its Strategic Missile Test and Production Complex in Promontory, Utah to gather data in regards to the weapon’s in-flight structural dynamics.
Northrop also tested the Sentinel’s shroud, which encases the payload inside the missile’s nose, in a fly-off test at Naval Air Weapons Station China Lake in California. This test, which the corporate said was successful, verified the shroud wouldn’t strike the enclosed payload because it flew off the missile.
The value tag for the Sentinel program has spiked enough to trigger a price overrun process often called a Nunn-McCurdy breach. Top Air Force leaders have pinned the majority of the associated fee growth on its highly complex command and launch segment, which involves securing real estate from lots of of landowners across the Midwest, constructing greater than 400 launch facilities and seven,500 miles of utility corridors, and laying hundreds of miles of fiber-optic networks.
The Air Force said the Sentinel missile itself will not be seeing as much of a severe cost growth as other portions of this system.
Sentinel, which was originally on account of reach initial operational capability in 2029, can be falling behind schedule by about two years, the Air Force said earlier this yr.
However the service is unlikely to cancel the Sentinel program over cost overruns and delays, and top leaders have said replacing the Minuteman III is so vital they might find money elsewhere within the budget to pay for the brand new ICBMs. The Pentagon is now reviewing Sentinel to see how it would restructure this system to get it back on target and convey down costs.
Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.