HILL AIR FORCE BASE — Don’t say goodbye to the Minuteman III ICBM system just yet.

The nuclear defense system, managed primarily out of Hill Air Force Base, is still a key pillar of U.S. defense and the U.S. Department of Defense has awarded Boeing Co. a $1.6 billion contract for intercontinental ballistic missile guidance subsystem support.

Some work related to the new Minuteman III contract will be handled at a Boeing facility in Heath, Ohio, but the “vast majority” of it will be completed out of Utah — Hill AFB and Boeing operations in Ogden and Layton, according to Boeing spokesperson Josh Roth.

The contract covers a 16-year span, through 2039, “and it is expected to support a significant amount of direct and indirect jobs in the area,” Boeing said in a statement issued out of its Huntsville, Alabama, office.

The U.S. Air Force eventually plans to replace the aging Minuteman III system with the Sentinel ICBM system. Northrop Grumman is leading development of that system in part out of new facilities taking shape in the Roy area around Hill and was awarded a $13.3 billion contract with the U.S. Air Force in 2020 to develop it.

However, the Sentinel system is to be deployed starting in the late 2020s, according to the U.S. Air Force, and the Minuteman III system is still a key prong of defense in the meantime.

“Boeing will maintain the around-the-clock readiness and accuracy of Minuteman ICBM guidance systems — which have logged more than 40 million hours of continuous operation — to ensure safe, secure and effective strategic deterrence into the late 2030s,” reads a Boeing statement.

Boeing is the only firm that has continuously supported all ICBM subsystems — guidance, ground, propulsion and reentry — over its lifetime, the company said. The Minuteman system was first deployed in the early 1960s.

“We built the Minuteman’s guidance system, so no one knows it like Boeing. Our highly-specialized facilities and top-flight engineers enable us to sustain it with unmatched quality and precision,” Ted Kerzie, program director of Strategic Deterrence Systems for Boeing, said in a statement. “We look forward to continuing our partnership with the Air Force on this all-important mission.”

The Sentinel ICBMs will eventually replace 400 Minuteman III ICBMs at missile fields at F.E. Warren AFB in Wyoming, Malmstrom AFB in Montana and Minot AFB in North Dakota, according to Air Force Nuclear Weapons Center information. Testing of Minuteman missiles takes place out of Vandenberg Space Force Base in California.

The ICBM system is one prong of the United State’s “nuclear triad,” the array of nuclear deterrence platforms and systems that can deliver strikes via land, sea and air. The Minuteman III system is maintained by the Ogden Air Logistics Complex at Hill.