Underwater speed records

Underwater speed record include records for submarines, autonomous underwater vehicles, and torpedoes. As these are typically for military vehicles, most are unconfirmed.

Submarines

Established reports and manufacturer's claims indicate that a handful of submarines are capable of speeds exceeding. In 1960, HMS Explorer S30 achieved an underwater speed of over 30 knots. In 1965, the experimental reported a speed of. The Soviet was found in 1968 to have a speed of . In response the United States Navy developed the, with a reported speed of. The -class vessel is reportedly capable of travelling submerged at. Its predecessor, the, could attain short speed bursts of while submerged. There are also claims that the Soviet twin-propeller submarine K-222, with titanium inner and outer hulls, reached, fully submerged, during sea trials in 1969.

Torpedoes

The British Spearfish torpedo, designed to counter high-speed Russian submarines such as the Alfa class, is reputed to reach speeds in excess of. The Russian VA-111 Shkval rocket-powered supercavitating torpedo is reportedly capable of speeds over. The German press reported on an underwater anti-torpedo missile, formerly named Barracuda, allegedly capable of reaching.