The US successfully tested a B61-12 tactical thermonuclear bomb without a warhead in August, according to a statement from the US Department of Energy’s Sandia National Laboratories.

The tests were conducted at a test site in Nevada from August 19 to 21, the statement said. During the tests, F-35 fighter jets delivered and dropped inert weapons. The tests were conducted in coordination with the National Nuclear Security Administration (NNSA).

The National Nuclear Security Agency completed a program to extend the service life of those aerial bombs by 20 years in late 2024, according to the statement.

The tests 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.

However, that was not the only significant first during these tests. The series also included the first-ever thermal preconditioning of a joint test assembly for carriage on an F-35 aircraft prior to its release, validating B61-12 environmental requirements in a real-world combined environment.

“These B61-12 F-35A stockpile flight tests and captive carry flight test were the capstone accomplishment of a tremendous amount of planning and effort by those who were involved across not only Sandia, but many other agencies,” said Sandia’s Jeffrey Boyd, surveillance lead for the B61-12 and B61-13. “In addition, these B61-12 stockpile flight tests represent the completion of the most B61-12 flight testing surveillance scope in a year to date and the most in a given year for the foreseeable future.”

Earlier, F-35A jets had received authorization to deploy B61-12 free-fall bombs, marking a historic milestone for the first fifth-generation aircraft to be approved for nuclear weapon carriage.

The certification announcement, clearing the way for nuclear weapon carriage, came on March 8, 2024, from Russ Goemaere, a spokesperson for the F-35 Joint Program Office, who disclosed it to Breaking Defense magazine. 

According to Goemaere, the certification was obtained on October 12, 2023, ahead of the timeline pledged to NATO allies, with completion scheduled for January 2024. With this achievement, the F-35A was designated a “dual-capable” platform, able to operate in both conventional and nuclear warfare scenarios. 

In contrast to the US Air Force’s F-22 Raptor, which primarily focuses on air-to-air combat, the F-35A was designed from the outset to incorporate tactical nuclear strike capabilities.  

Goemaere underlined the significance of this milestone, saying, “The F-35A is the first 5th generation nuclear-capable aircraft ever, and the first new platform (fighter or bomber) to achieve this status since the early 1990s.” 

The certification covers only the F-35A conventional takeoff and landing aircraft. It excludes other versions of the stealth fighter jet, such as the F-35B with short takeoff and vertical landing capabilities or the carrier-based F-35C. 

While China’s J-20 and Russia’s Su-57 also boast stealth capabilities, neither aircraft has yet attained the clearance for such operations. As a result, the F-35 stands out, with its unique combination of stealth and nuclear-strike capabilities.