Underwater speed record include records for submarines, autonomous underwater vehicles, and torpedoes. As these are typically for military vehicles, most are unconfirmed.
Established reports and manufacturer's claims indicate that a handful of submarines are capable of speeds exceeding 30 knots (56 km/h; 35 mph). In 1965, the experimental USS Albacore reported a speed of 33 knots (61 km/h; 38 mph).[1] The Soviet November-class submarine was found in 1968 to have a speed of 31 knots (57 km/h; 36 mph).[2] In response the United States Navy developed the Los Angeles-class submarine, with a reported speed of 30–32 knots (56–59 km/h; 35–37 mph). The Akula (Russian: shark)-class vessel is reportedly capable of travelling submerged at 35 knots (65 km/h; 40 mph). Its predecessor, the Alfa class, could attain short speed bursts of 40–45 knots (74–83 km/h; 46–52 mph) while submerged.[3][4] There are also claims that the Soviet twin-propeller submarine K-222, with titanium inner and outer hulls, reached 44.7 knots (83 km/h; 51 mph), fully submerged, during sea trials in 1969.
The British Spearfish torpedo, designed to counter high-speed Russian submarines such as the Alfa class, is reputed to reach speeds in excess of 70 knots (130 km/h; 81 mph). The Russian VA-111 Shkval rocket-powered supercavitating torpedo is reportedly capable of speeds over 200 knots (370 km/h; 230 mph).[5] The German press reported on an underwater anti-torpedo missile, formerly named Barracuda, allegedly capable of reaching 430 knots (800 km/h).[6]