The US Air Force Global Strike Command conducted a test launch of an unarmed Minuteman III Intercontinental Ballistic Missile (ICBM) on May 20. The test was conducted from the Vandenberg Space Force Base in California.

Keeping in mind the current geopolitical events, the US Air Force (USAF) has clarified that this is a routine launch and was scheduled years ago. As per the USAF press release, this launch designated GT 256 was conducted as a comprehensive operational test, designed to evaluate both the weapon system and the personnel who maintain it in a highly controlled testing environment.

It further quotes that this launch provides the opportunity for the engineers to meticulously track the flight path to evaluate the propulsion, guidance, and reentry systems of the ICBM under extreme physical stress. The test launch not only assesses the entirety of the ICBM mission set but provides various government agencies data from the complete end-to-end systems check.

This information is rapidly distributed to the Department of War, the Department of Energy, and U.S. Strategic Command to inform sustainment, engineering, and lifecycle analysis.

The Minuteman III ICBM

“Our ability to conduct these rigorous, realistic tests is foundational to our national security,” said Gen. S.L. Davis, commander of Air Force Global Strike Command.

“This launch verifies the health and readiness of our ICBM force, confirming the capability of every component of the ICBM enterprise, from our operators to the weapon system itself, to execute the mission.”

The silo based LGM-30G Minuteman III ICBM is one of the legs of the US nuclear triad, it entered service in 1970. The ICBM is a three stage solid rocket fueled system and is currently deployed in a single-warhead (W87) configuration, but could carry up to three warheads (W78). The missile has been tested to a range greater than 6,000 miles.

The current Minuteman III ICBM force consists of 400 missiles based in hardened silos located in Wyoming, Montana, Colorado, North Dakota, and Nebraska.

The USAF has replaced and updated many of the component systems on the missile through life-extension programs several times over the past 50 years. It has stated that some of these components may face reliability concerns as they reach the end of their intended lifespans.

The replacement LGM-35A Sentinel

After conducting an Analysis of Alternatives in 2014, the Air Force decided to replace Minuteman III with a new missile system that would serve till 2075. The USAF and Northrop Grumman (the lead contractor for the program), planned for the Sentinel to begin replacing Minuteman III in 2029.

The USAF plans to procure 634 Sentinel missiles, plus an additional 25 missiles to support development and testing, to enable the deployment of 400 missiles. It also originally planned to modernize 450 silos and over 600 facilities.

The USAF plans to initially deploy the Sentinel with the W87-0 warhead (currently deployed on the Minuteman III). The National Nuclear Security Administration (NNSA) is developing the W87-1 warhead, which, according to NNSA is slated to deploy between FY2031 and FY2032. Lockheed Martin is developing the Mk21A reentry vehicle for the W87-1. This reentry vehicle was tested in June 2024.

Currently Sentinel’s stage-one and stage-two rocket motors are undergoing testing. Reports suggests that the first test of the missile will be conducted from a launch pad instead of a silo.