The US Navy is hosting Japan’s Aegis destroyer JS Chokai for a yearlong training and upgrade program to integrate Tomahawk cruise missiles — a first for the Japanese fleet.
The deployment follows a January 2024 agreement between Tokyo and Washington to acquire 400 Tomahawk missiles.
Japan’s Ministry of Defense said that JS Chokai successfully carried out a dummy Tomahawk loading drill at Yokosuka before departing for the US.
The ship is set to return in 2026 with a certified crew, an upgraded combat system, and magazines ready for long-range precision strike.
Chokai by the Numbers
The JS Chokai is the fourth ship in the Kongō-class, a fleet of heavy Aegis destroyers based on the early designs of the US-made Arleigh Burke-class warships.
Weighing 9,500 tons (9,500,000 kilograms) when fully loaded, the vessel can reach 30 knots (56 kilometers/35 miles per hour) on four LM2500 gas turbines.
Its AN/SPY-1D phased-array radar, paired with the Aegis Baseline 5 combat system, has been steadily upgraded to bolster ballistic missile defense.
The destroyer carries 90 strike-length Mk 41 vertical launch cells, usually packed with SM-2 surface-to-air missiles, SM-3 interceptors, and VL-ASROC anti-submarine weapons.
These launchers are already compatible with Tomahawk, giving Chokai a smoother path to integration.
Additional armament includes a 127mm gun, two Phalanx close-in weapons, Harpoon anti-ship missiles, and torpedo tubes.
A flight deck supports helicopter operations, though the class lacks a hangar.
Training for a New Mission
While in the US, Chokai’s crew will complete certification in crane operations, canister handling, and Tomahawk fire-control procedures.
Training will also cover strike mission planning, target route design, and in-flight retasking using the missile’s two-way datalink.
Japan is acquiring the latest Block V Tomahawk, which has a range of about 1,000 miles (1,610 kilometers).
The weapon pairs GPS-INS guidance with terrain- and scene-matching, and can be upgraded to a Maritime Strike variant capable of engaging moving ships.
The new capability will shift Chokai’s role away from pure escort and area defense toward a distributed, sea-based strike role able to threaten airbases, logistics hubs, and missile sites.
