Air Force tests Mk21A reentry vehicle for Sentinel ICBM

AI-generated. This briefing was written by an AI model from published sources and was not reviewed by a person before publication. Check the original sources before relying on it.

Published: October 13, 2026

1 source

First reported by: Air & Space Forces Magazine

U.S. Air Force Nuclear Weapons CenterU.S. Space ForceLockheed MartinNorthrop GrummanSentinel (LGM-35A)Minuteman IIIVandenberg Space Force BaseW87-1

In brief

An unarmed Mk21A reentry vehicle flew on a Minotaur I launched from Vandenberg on Oct. 9, advancing testing for the Sentinel ICBM program.

Sources disagree

Factual claims where reporting sources diverge. Treat with care until confirmed by the primary investigator or regulator.

The failed 2022 Minotaur II+ test occurred on July 6 or July 7.
The Defense NewsWikipedia

The Air Force Nuclear Weapons Center tested a developmental Mk21A reentry vehicle on Oct. 9, launching it aboard a Minotaur I rocket from Vandenberg Space Force Base in California. The vehicle was unarmed. The test supports development of the reentry vehicle planned for the LGM-35A Sentinel intercontinental ballistic missile, which is intended to replace Minuteman III as the land-based component of the U.S. nuclear triad.

The launch is a test milestone, not evidence that the Sentinel missile or the Mk21A has entered service. The supplied coverage confirms the date, launch vehicle, site and…

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