Fastest submersible vehicle
The world’s fastest submersible vehicle is the K-222. Formerly K-162, it is also referred to as a “Papa”. A “Papa” is the western nickname for a Soviet Anchar submarine class. The Sub was commissioned on December 31, 1969, in Severodvinsk in the Soviet Union. Only one was built for the Soviet Northern Fleet. Now decommissioned, this submarine could travel as fast as 44.7 knots. This record-breaking speed, however, came with a price. Not only was the sub expensive to build but during speed tests it made “excessive noise” and would experience “significant damage” to its hull.
(Image courtesy of Ajjafh)