A Higher Yield Nuclear Bomb For the F-35 Stealth Fighter: U.S. Preparing to Produce B61-13

Production of the U.S. Armed Forces’ latest class of tactical nuclear bomb, the B61-13, is scheduled to begin in June 2025, with the program intended to provide a new much higher yield class of modern nuclear weapon for the country’s combat aviation assets including its <a href="https://militarywatchmagazine.com/article/f35-program-cost-2trillion" target="_blank">F-35 stealth fighters</a>. The U.S. Armed Forces announced plans to develop&nbsp;the new bomb on October 27, 2023, with the Pentagon announcing at the time: "The B61-13 would take advantage of the current, established production capabilities supporting the B61-12, and would include the modern safety, security, and accuracy features of the B61-12.” The new bomb&nbsp; has a maximum yield of approximately 360 kilotons compared to a maximum yield of around 50 kilotons on the widely used B61-12 bomb and a yield of just 15 kilotons on the Little Boy bomb used to destroy the Japanese city of Hiroshima in 1945. A Pentagon report summarised at the time that the new bomb was intended to “provide the President with additional options against certain harder and large-area military targets.” National Nuclear Security Administration (NNSA) acting head Teresa Robbins informed Congress on May 7 that the bomb “strengthens deterrence and assurance by providing the President with additional options against certain harder and large-area military targets.”&nbsp;<img src="https://militarywatchmagazine.com/m/articles/2025/05/12/article_6821c37dc799f1_64114996.gif" title="B61-12 Bomb">Rising tensions with leading adversaries benefitting from heavily fortified military sites has led to greater importance being attributed to an the ability to launch higher yield tactical nuclear attacks. North Korea in particular has been a leader in proliferating fortification technologies and provided hardening for Iranian and Hezbollah facilities. The B61-13’s entry into production is particularly significant due to its planned compatibility with the F-35, which other than a <a href="https://militarywatchmagazine.com/article/usaf-b2-accident-fleet-19" target="_blank">small fleet of under 20</a> B-2 bombers, is the only stealth aircraft in the Western world capable of launching nuclear attacks. With the U.S. Armed Forces expected to field close to 2000 F-35s, the ability to launch very high yield nuclear attacks using any of these operating from bases and warships across the world presents adversaries with a particularly significant nuclear threat. The issue of the F-35’s nuclear capabilities has been particularly sensitive for Russia, with <a href="https://militarywatchmagazine.com/article/f35-bomb-one-fighter-310000-russians" >assessments</a> in November 2023 having concluded that the new <a href="https://militarywatchmagazine.com/article/f35-larger-nuclear-penetrate-targets" >B61-13 tactical nuclear bomb</a>&nbsp;would allow a single F-35 to kill up to approximately 360,000 inhabitants of major Russian cities in a single strike. &nbsp;