The National Nuclear Security Administration has completed all W80-4 nuclear warhead components planned for fiscal year 2026 months ahead of schedule, giving the agency additional schedule margin as it works toward delivering the first complete warhead in September 2027.

The milestone was reached at the Kansas City National Security Campus, where production teams completed the components planned for the fiscal year, according to an agency press release. NNSA said the remaining W80-4 components are on track to enter their production phase in early calendar year 2027.

The W80-4 is the life-extension version of the legacy W80-1 warhead and is being developed for the Air Force’s Long-Range Standoff, or LRSO, cruise missile. The LRSO is intended to replace the Air-Launched Cruise Missile and will be carried initially by the B-52H bomber, with the B-21 Raider expected to eventually carry the weapon.

NNSA previously set September 2027 as the W80-4’s First Production Unit date. The agency said the accelerated component production provides additional margin as teams across the Nuclear Security Enterprise work toward that system-level milestone.

The W80-4 program is intended to extend the service life of the W80 design while incorporating modern components and safety features. The program also includes a modern digital interface with the LRSO missile and makes use of selected components from legacy warheads, allowing some existing hardware to be reused rather than completely remanufactured.

“Accelerating production and delivering ahead of schedule wherever possible, while meeting our high standards for safety and security, are becoming central to NNSA’s culture,” NNSA Administrator Brandon Williams said.

“America’s adversaries are not delaying in upgrading their nuclear arsenals, and we are meeting their challenge with a sense of urgency not seen since the Cold War,” Williams said.

NNSA Deputy Administrator for Defense Programs David Beck joined the W80-4 team at Kansas City to mark the production milestone.

“Administrator Williams’ mantra of ‘Deterrence, Urgency, and Production’ is yielding results across the nuclear enterprise,” Beck said. “Completing all the planned components for the W80-4 this year is a tremendous example of urgency driving technical precision and production excellence.”

The Kansas City milestone is one part of a broader production effort involving multiple sites across the Nuclear Security Enterprise.

Lawrence Livermore National Laboratory is the design agency for the W80-4, working with Sandia National Laboratories, production agencies and the Air Force. LLNL’s physics and engineering designs have supported production engineering and component development.

The Y-12 National Security Complex is producing three major components for the warhead, while Pantex is responsible for explosives components and eventual final assembly. Los Alamos National Laboratory is the production agency for four nuclear components. Kansas City serves as the primary non-nuclear production agency and is supporting production readiness.

NNSA has already recorded an early production milestone on the program. In September 2025, Y-12 completed and certified the First Production Unit of a canned subassembly for the W80-4, with NNSA describing the milestone as being achieved ahead of schedule. The completed subassemblies are returned to Pantex for final assembly.

The W80-4 program entered Phase 6.4, or Production Engineering, in March 2023 after completing its preliminary design and system-level engineering reviews. At that point, NNSA established September 2027 as the FPU date.

The program’s production work is occurring as NNSA seeks to expand manufacturing capacity across the Nuclear Security Enterprise and accelerate delivery of modernized warheads. The agency’s broader modernization effort is intended to sustain the U.S. nuclear stockpile without the need for additional nuclear explosive testing.

For the W80-4, production teams are coordinating manufacturing, qualification and integration activities across the enterprise as they move toward the complete-warhead FPU.

NNSA said the completion of the fiscal 2026 component workload at Kansas City is expected to provide additional schedule margin and maintain momentum toward delivery of the first complete W80-4 in 2027.