Japan conducts world’s first successful electromagnetic railgun test at sea

In a breakthrough for naval weapons technology, the Japan Maritime Self-Defense Force (JMSDF) has announced the world’s first successful at-sea test of an electromagnetic railgun. The live-fire demonstration took place on Wednesday in Tokyo Bay, with the weapon mounted on the bow of the experimental vessel JS Asuka.

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14 september 2025 | 09:20 | Source: Gazeta Morska / PAP | Prepared by: Kamil Kusier | Print

fot. ATLA / x.com

The railgun, weighing more than eight tons, fired a projectile at a muzzle velocity of approximately 2,230 m/s (around Mach 6.5), striking and destroying a moored target vessel off the coast of Yokosuka. The JMSDF released photographic evidence of the test on social media, confirming the strike.

The program is jointly developed by Japan’s Acquisition, Technology & Logistics Agency (ATLA) and Japan Steel Works, a major domestic defense manufacturer.

Unlike conventional naval guns, the electromagnetic railgun uses pure kinetic energy to launch inert projectiles at hypersonic speeds. This makes the ammunition significantly cheaper, lighter, and inherently safer, as it contains no explosive filler and therefore cannot detonate in storage or during enemy attack. Defense analysts at Shephard Media estimate the projectiles used in the test to be 40 mm rounds weighing roughly 320 grams.

Beyond cost and safety benefits, the system offers substantial operational advantages. It can function in all weather conditions and has the potential to engage targets beyond the visual horizon, a capability highly sought after for maritime operations. Japanese planners also expect the railgun to be effective against a range of modern threats — including hostile surface vessels, drones, and even hypersonic missiles — once it reaches full operational capability.

The United States Navy previously invested more than $500 million into a similar railgun program but officially halted development in 2021. Japan’s continued progress positions it as a frontrunner in the global race to field practical electromagnetic weapon systems, potentially shaping the future of naval firepower for decades to come.

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Kamil Kusier
redaktor naczelny

działo elektromagnetyczne marynarka wojenna Japonii JS Asuka broń hipersoniczna railgun