A military rocket exploded Wednesday during the first test launch of a key component of America’s future land-based nuclear missiles.
The rocket, known as the Minotaur II+, blew up about 10 seconds after launching from Vandenberg Space Force Base, California, around 11 p.m. local time.
“There were no injuries in the explosion and the debris was contained to the immediate vicinity of the launch pad,” the base said.
Officials will investigate the cause of the mishap.
The Minotaur II+ combines parts of decommissioned Minuteman intercontinental ballistic missiles and an upper segment of the current Minuteman III nuke to create a missile used for suborbital test launches.
Vandenberg routinely holds live tests of unarmed missile bodies — without a nuclear warhead inside — to check how the aging ICBMs are faring and to vet new technology.
In this case, the Air Force Nuclear Weapons Center said the practice missile was carrying a Mark 21A reentry vehicle, or the part of a nuclear weapon that would hold a real warhead.
Military officials are gathering “detailed, reliable” data that will help shape the prototype system into the final product, according to the service.
The Air Force has contracted with Lockheed Martin to redesign the Mk21A to carry 300-kiloton W87-1 nuclear warheads — 15 times the explosive power of the “Fat Man” bomb dropped on Nagasaki, Japan, in 1945 — on the LGM-35 Sentinel missile now in development at Northrop Grumman.
“The W78 is one of the oldest warheads in the stockpile, and the W87-1 modification program provides improvement in warhead security, safety and … control,” according to the Energy Department, which manages the program.
The updated reentry vehicle, which carries the warhead to the edge of space in an arc before gliding down to its target, is also expected to accommodate future warhead designs on the new ICBMs in the coming decades.
Sentinel ICBMs will replace the 400 nuclear missiles in underground silos across Montana, Wyoming and North Dakota in the late 2020s.
Rachel Cohen is the editor of Air Force Times. She joined the publication as its senior reporter in March 2021. Her work has appeared in the Washington Post, the Frederick News-Post (Md.), Air and Space Forces Magazine, Inside Defense, Inside Health Policy and elsewhere.