X-class submarine
British midget submarine of The Second World War
On 22 September 1943 two X-class midget submarines, towed to Norway by full-size boats, laid charges under the battleship Tirpitz in Kaafjord. Analysts in 2026 see the same mothership method in a Chinese hull built for uncrewed submarines.
Last refreshed: 7 October 2026
Timeline for X-class submarine
Mentioned in: China may build a drone-sub mothership
Autonomous Systems: Land & SeaBackground
The X-class was a Royal Navy midget submarine that entered service in 1943, built to attack large ships at their moorings. Each had a CREW of four and carried two detachable side charges, each of two tons of explosive, to drop beneath a target's hull.
In Operation Source, six full-size submarines towed six X-craft across the North Sea to Norway, because the midgets lacked the range to make the crossing alone. On 22 September 1943 X6 and X7 laid their charges under the Tirpitz in Kaafjord. Both commanders, Lieutenants Donald Cameron and Godfrey Place, won the Victoria Cross.
The X-craft showed that a short-range craft can hit a distant target if a larger vessel carries it most of the way. Naval analysts now apply the same idea to uncrewed submarines. On 15 September 2026 Naval News read satellite images of a hull taking shape in Shanghai, at the Hudong-Zhonghua yard, as a Chinese carrier for very large robot submarines, its hangar big enough for four.