America’s newest air-dropped nuclear weapon variant has entered production. The U.S. Department of Energy’s National Nuclear Security Administration (NNSA) announced that on November 23, it had successfully completed the first production units of the B61-12 Life Extension Program (LEP), an updated version of the warhead used on weapons dropped from fighters and bombers. This paves the way to create an estimated 480 of the weapons, which will homogenize four existing variants of the bomb.

The B61-12 LEP helps modernize America’s nuclear weapons stockpile and sustain the Nation’s air-delivered nuclear deterrent capability. The nuclear security enterprise and the U.S. Air Force worked together to deliver the B61-12 FPU after more than nine years of design, development, qualification, and component production.

Deployed from U.S. Air Force and North Atlantic Treaty Organization (NATO) bases, the B61 nuclear gravity bomb has been in service for over 50 years. Since the first B61 entered services in 1968, many modifications have been made to improve the B61’s safety, security, and reliability. Currently, there are four B61 variants remain in the stockpile: the 3, 4, 7, and 11. The B61-12 will replace the B61-3, 4, and 7.