An inert Sentinel intercontinental ballistic missile erected on a test-pad at Vandenberg Space Force Base recently. A test launch early Friday morning from the base using a Minotaur vehicle carrying modern re-entry vehicle marked one more milestone toward the development of the Sentinel next-generation ICBM. A flight test for the Sentinel program is planned for 2027.
An inert Sentinel intercontinental ballistic missile erected on a test-pad at Vandenberg Space Force Base recently. A test launch early Friday morning from the base using a Minotaur vehicle carrying modern re-entry vehicle marked one more milestone toward the development of the Sentinel next-generation ICBM. A flight test for the Sentinel program is planned for 2027. Credit: Northrop Grumman photo

The Air Force conducted a missile test from Vandenberg Space Force Base early Friday morning as part of the ongoing efforts to develop a next-generation weapon system which may see its debut flight next year. 

Few details were released late Thursday night but base officials announced the test involving a Minotaur launch vehicle would occur before 6 a.m. Friday. 

The test launch carrying the unarmed Mk21A reentry vehicle occurred at 12:43 a.m. from North Base where multiple underground missile silos and other facilities dot the landscape. 

Notices advising pilots and mariners about the upcoming test were released several days ago with a reference pinpointing the purpose as part of the Air Force’s development of a new intercontinental ballistic missile.

Friday afternoon, military officials confirmed the test took place, but continued to release limited information. Patchy fog interfered with attempts to capture pictures of the test.

“The Mk21A is crucial to modernizing our ICBMs in response to the rapidly changing global threat picture posed by our adversaries,” said Maj. Gen. William Rogers, Air Force portfolio acquisition executive for ICBMs and AFNWC director of ICBM systems. “The reentry vehicle’s development will ensure a safe, secure and effective deterrent for generations to come.”

The military has contracted with Lockheed Martin Corp. for the Mk21A reentry vehicle’s engineering and manufacturing development phase. 

For the testing purpose, the unarmed Mk21A reentry vehicle test unit was launched aboard a Minotaur I rocket provided by Northrop Grumman and overseen by the U.S. Space Force’s Rocket Systems Launch Program. 

Once deemed fully operational capability, the Mk21A RV will be integrated on a future intercontinental ballistic missile (ICBM).

Another test from Vandenberg occurred in June 2024, but a similar mission in 2022 ended in failure 11 seconds after launch from Vandenberg.

The Air Force Nuclear Weapons Center, based in New Mexico, is currently spearheading development of the new reentry vehicle.

“Investment in modernization of the ICBM mission remains a top priority for the Air Force,” said Brig. Gen. General Amanda Okeson, program manager, AFNWC ICBM Systems Directorate.

Fog hampered hopes of capturing a Minotaur I vehicle launch early Friday morning from north Vandenberg Space Force Base, where a similar test carrying an unarmed Mk21A reentry vehicle launched in June 2024. Northrop Grumman’s Minotaur uses retired missile stages and new components to conduct tests for military programs. The new reentry vehicle is one part of development for a new intercontinental ballistic missile, dubbed Sentinel and set for flight test in 2027.
Fog hampered hopes of capturing a Minotaur I vehicle launch early Friday morning from north Vandenberg Space Force Base, where a similar test carrying an unarmed Mk21A reentry vehicle launched in June 2024. Credit: U.S. Space Force photo

The Air Force is developing a next-generation intercontinental ballistic missile under the Ground-Based Strategic Deterrent weapon system, also known as Sentinel.

As part of the that effort, the military and defense contractors have been working to modify the existing Mk21A re-entry vehicle, typically a cone-shaped device that sits inside a missile’s nosecone. Re-entry vehicles carry a warhead for the final leg of a trip toward the target.

The program seeks to tweak the older Mk21A re-entry vehicle with the capability to deliver the W87-1 warhead for Sentinel.

Last month, the Air Force announced the Sentinel intercontinental ballistic missile program reached a critical milestone by completing the vertical stacking of the inert vehicle at Vandenberg.

The stacking served as a key step to assess the missile’s design and verify critical subsystems ahead of initial flight testing, which is planned for 2027.

“This is more than a milestone, this integration demonstrates our commitment to moving forward with the pace necessary to modernize the ground-based leg of our nuclear triad and deliver critical capability to the warfighter,” said Gen. Dale White, director of Critical Major Weapon Systems for the Defense Department.

— Noozhawk North County editor Janene Scully can be reached at jscully@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.