Lockheed Martin Completes Flight Test of Mk21A Reentry Vehicle for Sentinel ICBM Nuclear Warheads

Lockheed Martin and the U.S. Air Force completed a developmental flight test of the unarmed Mk21A reentry vehicle from Vandenberg Space Force Base, California, over the Pacific. The vehicle is designed to carry the National Nuclear Security Administration’s W87-1 warhead on the LGM-35A Sentinel intercontinental ballistic missile and combines thermal protection with arming, fuzing and warhead interface hardware. Lockheed Martin announced the result on November 4 and said flight data would inform design refinements ahead of the system-level critical design review, which the Air Force has scheduled by March 2027.