The Air Force on Wednesday morning launched a non-nuclear Minuteman III missile, carrying what the service called a “high-fidelity joint test assembly,” from Vandenberg Air Force Base in California.

The Air Force announced the early-morning launch in a press release.

Supporting the test launch from the West Coast were Air Force personnel from the 341st Missile Wing at Malmstrom Air Force Base in Montana, the 90th Missile Wing at F.E. Warren Air Force Base in Wyoming, and the 91st Missile Wing at Minot Air Force Base in North Dakota, the service said in the release.

The Minuteman III detonated a conventional explosive just before splash down some 4,200 miles downrange near Kwajalein Atoll in the Marshall Islands, according to the Air Force.

A joint test assembly is a non-nuclear testbed for electronics and sensors. These units are “[a]n NNSA [National Nuclear Security Administration]-developed configuration, based on NNSA-DoD requirements, for use in the flight test program,” according to the NNSA’s 2021 Stockpile Stewardship and Management Plan. The civilian weapons agency book keeps joint test assembly funds in the stockpile sustainment program.

A version of this story first appeared in Defense Daily affiliate publication, Weapons Complex Morning Briefing.