Railgun Damage To Japanese Target Ship Seen For The First Time

Japan’s Acquisition Technology & Logistics Agency (ATLA) has offered the first look at damage to a target ship after it was hit by projectiles fired from a prototype electromagnetic railgun in testing earlier this year. Japanese authorities say valuable data and experience were gleaned from the demonstration, which will feed into its continued push toward an operational railgun capability. This is an area of development where the U.S. Navy notably halted work in the early 2020s, despite having seen promising progress, due to significant technological impediments.

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Railguns, in general, use electromagnets instead of chemical propellants to fire projectiles at very high velocities. Dart-shaped projectiles, each with four fins at the rear and no warhead, were fired during the at-sea tests earlier this year. The projectiles were initially held inside a sabot that broke apart after leaving the muzzle. There was also a metal armature at the rear that served to push the projectile in the sabot down the barrel, which fell away after firing.

A slide from the ATLA presentation this week highlighting the evolution from earlier prototype railguns tested at facilities on land to the one mounted on the JS Asuka for the at-sea tests. ATLA

Another slide from the presentation discussing the design of the projectiles fired during the at-sea testing. ATLA
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The wear on barrels from the sustained firing of projectiles at very high speeds is one of a number of long-standing challenges for railguns, in general. A worn-out barrel can lead to the loss of range and accuracy, as well as increase the risk of a catastrophic failure.

Railguns also have significant power generation and cooling requirements, which have, in turn, historically made them very physically bulky. The installation on JS Asuka included four shipping containers full of additional systems and equipment to help meet those needs.

Kazumi Ito, principal director of the equipment policy division at ATLA, said his country’s railgun efforts were “progressing,” but acknowledged “various challenges,” while speaking through an interpreter at a panel discussion at the DSEI Japan 2025 exposition earlier this year, according to National Defense Magazine.

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“When it comes to warships, in particular, where physical space is at a premium and where options for reloading missiles at sea can be at best extremely limited, having a weapon system firing lower-cost munitions from a large magazine and that can engage a broad swath of target sets would be a clear boon.”
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