The US Department of Energy’s National Nuclear Security Administration (NNSA) marked a historic milestone last December 18, 2024, as it completed the final production unit of the B61-12 Life Extension Program (LEP). This achievement underscores the critical role of the B61 family in the US nuclear arsenal and highlights the NNSA’s commitment to sustaining a robust and modern nuclear deterrence capability.

A Modern Solution to a Legacy Weapon

The B61 family of nuclear gravity bombs first introduced more than 50 years ago, is the longest-serving and most versatile weapon in the US nuclear stockpile.

Designed to be deployed from US Air Force and NATO bases, the B61 has been a cornerstone of air-delivered nuclear deterrence.

The B61-12 LEP, initiated in 2008, extends the bomb’s service life by at least 20 years through comprehensive refurbishments.

The program includes replacing or reusing all nuclear and non-nuclear components and consolidating four older variants (-3, -4, -7, and -10) into a single, modernized design.

B61 gravity bombs
B61s on a bomb rack. (Wikimedia Commons)

What sets the B61-12 apart is its balance between improved precision and reduced yield.

Enhanced by a modern tail kit assembly, the weapon delivers greater accuracy while maintaining its military characteristics. This approach reflects a strategic shift toward precision-targeting capabilities that minimize collateral damage, aligning with evolving defense needs.

Collaboration and Execution at Scale

The success of the B61-12 LEP represents a collaborative triumph involving key facilities such as Los Alamos National Laboratory, Sandia National Laboratories, the Pantex Plant, and others.