The Department of Energy’s National Nuclear Security Administration has announced the completion of the last production unit of the W88 Alteration 370 program, marking the conclusion of a multi-year modernization effort for the W88 nuclear warhead on Ohio-class ballistic missile submarines.
The completion represents the final phase of one of seven active warhead modernization initiatives, NNSA said Tuesday.
What Is the W88 Alteration Program?
The program addressed aging concerns of the W88 nuclear arsenal discovered during routine inspections. It is intended to sustain the reliability of the sea-based leg of the strategic deterrent.
The effort involved replacing the warhead’s arming, fuzing and firing assembly, installing a lightning arrestor connector, refurbishing the conventional high explosives and replacing limited-life components at the same time.
NNSA completed delivery of the final W88 Alt 370 warhead four years after the first production unit was achieved in July 2021. The program involved Los Alamos and Sandia National Laboratories, the Pantex Plant, Y‑12 National Security Complex and the Kansas City National Security Campus for design, development, testing and component production.
“Completing the W88 Alt 370 is the latest instance of NNSA delivering modernized nuclear weapons to the Department of War at the pace and scale needed to fulfill our deterrence requirements. Achieving two LPUs for the B61-12 and W88 and the FPU for the B61-13 all within a single year demonstrates our ability to execute NNSA’s fundamental production mission,” said NNSA Administrator Brandon Williams.
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