Tench-class submarine

Tench-class submarines were a type of submarine built for the United States Navy (USN) between 1944 and 1951. They were an evolutionary improvement over the Gato and Balao classes, only about 35 to 40 tons larger, but more strongly built and with a slightly improved internal layout. Further improvements were made beginning with SS-435, which are sometimes referred to as Corsair class.

Initial plans called for 146 to be built, but 115 were cancelled in 1944 and 1945 when it became apparent that they would not be needed to defeat Japan. The remaining 31 were commissioned between October 1944 (Tench) and February 1951 (Grenadier).

One Tench (ex-Cutlass) was transferred from the USN to the Republic of China Navy as Hai Shih. Two went to Italy as the Gianfranco Gazzana-Priaroggia class. USS Argonaut (SS-475) was sold to the Royal Canadian Navy in 1968, renamed HMCS Rainbow, and decommissioned in 1974.

Some of the class were updated through the GUPPY (The Greater Underwater Propulsion Power Program). The difference is noticeable by the level foredeck and the rounded bow.



Museums
Three Tench Class submarines are on display for the general public.
 * USS Requin (SS-481) at the Carnegie Science Center in Pittsburgh, PA.
 * USS Torsk (SS-423), moored at Pier Three, Baltimore's Inner Harbor, (alongside the National Aquarium in Baltimore) in Maryland.
 * USS Thornback (SS-418), on display at Rahmi M. Koç Museum, Golden Horn in Istanbul.