US Completes Assembly of First B61-13 Nuclear Bomb

The US National Nuclear Security Administration (NNSA) has announced the completion of the assembly of the first B61-13 nuclear aerial bomb at the Pantex Plant in Amarillo, Texas, nearly a year ahead of schedule. The development of the B61-13, which began in 2023, marks one of the fastest advancements in the history of the US nuclear arsenal since the Cold War. The bomb is specifically designed to target heavily fortified underground military facilities, such as command bunkers and weapon depots, and will be deployed by strategic bombers, including the B-21 Raider.

As the latest iteration of the B61 family of nuclear gravity bombs, the B61-13 has been a cornerstone of the US air-launched nuclear triad for over 50 years. According to the NNSA, the bomb incorporates the manufacturing capabilities established with the B61-12, the last batch of which was completed in December 2024. While the B61-13 shares the same safety, precision, and control systems as its predecessor, it boasts a higher maximum yield of 360 kilotons—24 times more powerful than the bomb dropped on Hiroshima.

US Energy Secretary Chris Wright, who awarded the first bomb a gold star of excellence during a ceremony on May 19, commented, “The speed of B61-13 production demonstrates the ingenuity of our scientists and the urgency of strengthening deterrence in a new, volatile era.” He emphasized that the bomb serves as a clear signal to both adversaries and allies that the United States is prepared to meet modern challenges. Set to begin full production in 2026, the B61-13 will not expand the overall nuclear arsenal, as each new bomb will replace an existing B61-12 and facilitate the retirement of older B61-7 and B83-1 megaton warheads.

The development of the B61-13 has sparked controversy. The Federation of American Scientists (FAS) argues that its creation is more of a political maneuver aimed at persuading Congress to approve the deployment of the B83-1 rather than a genuine military necessity, given that the B61-12 is already capable of striking most targets with reduced collateral damage. The B61-13’s high precision, enhanced by its TKA, allows it to deliver effects comparable to a megaton surface explosion through the phenomenon of seismic impact.