U.S. Deputy Secretary of Energy James P. Danly participated in the diamond-stamping of the First Production Unit (FPU) of a canned subassembly (CSA) for the W80-4 Life Extension Program at the National Nuclear Security Administration (NNSA)’s Y-12 National Security Complex in Oak Ridge, Tennessee. The CSA component is the “secondary” stage of a modern two-stage thermonuclear weapon. Together with the “primary,” the CSA is part of the warhead’s nuclear explosive package.

“For 80 years, the nuclear deterrent has been the cornerstone of our nation’s defense, and we’re dedicated to modernizing the stockpile in order to ensure the future security of the United States," said Deputy Secretary James P. Danly. "I commend the team at Y-12 for this accomplishment.”

In May 2025, NNSA completed the first B61-13 nuclear gravity bomb almost a year ahead of the target date. U.S. Secretary of Energy Chris Wright was present at Y-12 for the diamond-stamping of that bomb’s CSA in February. Today’s stamping marks the second in a single year at Y-12.

“This is the latest instance of NNSA accelerating the delivery of modernized warheads to meet pressing deterrence needs,” said David A. Hoagland, acting Deputy Administrator for Defense Programs. “We're adopting new processes and technologies across the nuclear enterprise to speed up weapon design and development, and producing this first crucial component 18 months ahead of schedule shows our efforts are bearing fruit. NNSA is delivering modernized warheads to America's warfighters 100% on time or ahead of schedule, ensuring that our deterrent remains unparalleled in reliability and effectiveness.”

Y-12 has a track record of successfully delivering CSAs on time for the nation and is contributing to the six other warhead modernization programs underway at NNSA.

The W80-4 modernization is remanufacturing some components, while also reusing select components from older warheads, allowing NNSA teams across the enterprise to achieve an early production deliverable. Ahead of Y-12 completing the first CSA for the program, Lawrence Livermore National Laboratory in California provided physics and engineering designs, and the Pantex Plant in Texas disassembled legacy stockpile warheads to harvest components for reuse during processing at Y-12. Completed CSAs will be returned to Pantex for final assembly.

Once completed, the W80-4 program will provide warheads for the U.S. Air Force’s planned Long-Range Standoff (LRSO) cruise missile, which will replace the Air Launched Cruise Missile and will provide the President with additional flexible nuclear options.

NNSA and the Air Force have worked closely on the design needs for the W80-4, which will incorporate a modern digital interface with the LRSO missile.