By Oleh Velhan November 15, 2025
Thank you for reading this post, don't forget to subscribe!The United States successfully conducted a flight test of a B61-12 tactical thermonuclear gravity bomb without its nuclear warhead in August 2025, according to a statement released by Sandia National Laboratories, which operates under the U.S. Department of Energy.
The tests were conducted at the Tonopah Test Range in Nevada between August 19 and 21. During the trials, F-35 fifth-generation fighter jets delivered and released the bombs, which contained inert (non-nuclear) payloads.
Sandia National Laboratories provided details on the operation:
“Sandia, in conjunction with NNSA, conducted a series of successful stockpile flight tests at Tonopah Test Range in Nevada, with support and aircraft generation from Hill Air Force Base in Utah. The tests, conducted Aug. 19-21, yielded positive results as inert units of the B61-12 nuclear gravity bomb were successfully carried and dropped by an F-35 aircraft, marking a significant milestone in evaluating the weapon’s performance.”
The laboratory further noted that the August tests were critical for the F-35 platform’s readiness:
“The August tests were the only B61-12 stockpile flight tests of joint test assemblies on an F-35 aircraft, solidifying the end-to-end reliability of the aircraft, crews, and weapon system during missions.”
This testing follows the completion of a significant modernization effort. At the end of 2024, the National Nuclear Security Administration (NNSA) completed a multi-year life-extension program for the B61-12, extending the bomb’s service life by at least 20 years.
The B61-12 is a modernized, low-yield tactical nuclear bomb equipped with a precision-guidance system. It is designed to be compatible with multiple delivery platforms, including the F-35A Lightning II fighter jet.
In related news, media outlets reported this past summer that the United States had deployed nuclear weapons—specifically, several B61-12 thermonuclear warheads—to the United Kingdom for the first time since 2008. These weapons were reportedly placed in a new hardened storage facility at RAF Lakenheath in Suffolk. Defense officials in both the U.S. and the U.K. declined to comment on those reports.
The successful flight test of the non-nuclear assembly is part of the U.S.’s ongoing effort to ensure the safety, security, and effectiveness of its nuclear deterrent without conducting full nuclear detonations.
