US to introduce new nuclear gravity bomb design: B61-13

The Biden administration announced today its intention to create a new variant of America’s nuclear gravity bomb, dubbed the B61-13, Defense News reports.

The decision is a direct result of the findings from the 2022 Nuclear Posture Review and seeks to give the US “additional options against certain harder and large-area military targets,” according to a Pentagon fact sheet [PDF] that accompanied the announcement.

In a statement, Assistant Secretary of Defence for Space Policy John Plumb said the decision “is reflective of a changing security environment and growing threats from potential adversaries. The United States has a responsibility to continue to assess and field the capabilities we need to credibly deter and, if necessary, respond to strategic attacks, and assure our allies.”

While the DoD has oversight of the delivery systems for nuclear weapons, all nuclear warhead modernization is run through the National Nuclear Security Administration (NNSA), a semi-independent branch of the Department of Energy.

The new design will build on the ongoing B61-12 life-extension program, which has its origins in the Obama administration. That effort is consolidating the older B61-3, -4, -7 and -10 variants while updating with newer technologies.

The first production unit of the B61-12 rolled out in November 2021, with production scheduled through the end of fiscal 2025. The program is estimated to cost $9.6 billion in FY22 dollars over its lifespan, although much of that cost has already been spent, according to an annual government accounting of nuclear warheads.