NNSA completes B61-12 Life Extension Program

WASHINGTON – On December 18, 2024, the U.S. Department of Energy’s National Nuclear Security Administration (NNSA) completed the Last Production Unit (LPU) of the B61-12 Life Extension Program (LEP). The B61-12 is the latest modification to the B61 family of gravity bombs, which are deployed from U.S. Air Force and North Atlantic Treaty Organization bases. The B61 family of bombs has over 50 years of service, making it the oldest and most versatile weapon in the enduring U.S. nuclear weapon stockpile. The B61-12 LEP, which is critical to sustaining the Nation’s air delivered nuclear deterrent capability, extends the service life by at least 20 years through refurbishing, reusing, or replacing all the bomb’s nuclear and non-nuclear components.



“Completing the B61-12 on schedule is the latest example of what we’ve been saying for several years now: NNSA is delivering capabilities at the pace and scale needed by our Department of Defense partners and our deterrence requirements,” said Under Secretary of Energy for Nuclear Security and NNSA Administrator Jill Hruby.

This LEP, which began in 2008, will continue to assure its safety, security, and effectiveness and consolidated and replaced the -3, -4, -7, and -10 B61 variants. The B61-12 balances greater accuracy provided by the modern tail kit assembly with a substantial reduction in yield, with no overall change in military characteristics.

The Nuclear Security Enterprise, in close coordination with the U.S. Air Force, worked together to deliver the B61-12 LPU three years after achieving First Production Unit in November 2021 and 17 years after design and development activities first started. NNSA’s program managers and experts from Los Alamos National Laboratory, Sandia National Laboratories, the Pantex Plant, the Savanah River Site, the Y-12 National Security Complex, and the Kansas City National Security Campus worked in close collaboration with NNSA on the design, development, qualification, and component production.

“Completion of the last B61-12 testifies to the successful collaboration we’ve had with our U.S. Air Force and Department of Defense partners. The momentum built through B61-12 production and delivery will continue into delivery on the other six active weapons modernization programs and on additional programs that will become active in the coming years,” said Dr. Marvin Adams, Deputy Administrator for Defense Programs. “Achieving LPU in FY 2025 demonstrates our ability to execute, not only to our partners and stakeholders in DoD and Congress but also to our adversaries and allies. This demonstration is itself a contribution to deterrence and assurance.”

With production of the B61-12 LEP now complete, NNSA will transition to producing the B61-13 bomb, which will leverage the current, established production capabilities supporting the B61-12. FPU of the B61-13 is scheduled for FY 2026.

NNSA continues to pursue six additional warhead modernization programs while also modernizing the full suite of production manufacturing capabilities necessary to develop a more resilient Enterprise to meet evolving nuclear deterrence objectives.