Tench-class submarine

Tench-class submarine. The Tench-class submarines were a class of United States Navy Fleet submarines active during the final year of World War II and throughout the Cold War. Representing the ultimate refinement of American Gato and Balao class designs, they incorporated critical improvements in hull strength, machinery layout, and underwater performance. Although many were completed too late to see significant action in the Pacific War, they formed a backbone of the postwar United States Submarine Force and served in various roles, including with allied navies, for decades.

Design and development

The design evolved directly from the preceding Balao-class submarine, with the primary goal of increasing test depth through the use of higher yield strength HY80 steel. Key modifications included relocating the air conditioning and refrigeration machinery below the main deck to lower the ship's center of gravity and improve stability. The internal ballast tanks were also rearranged, and the Fairbanks-Morse opposed-piston diesel engines were upgraded for greater reliability. These changes resulted in a more robust and capable boat, though externally they were nearly identical to the late-war Balao-class boats built at the Portsmouth Naval Shipyard.

Service history

Only a handful of the class, including the lead boat USS Tench (SS-417), conducted war patrols before the Surrender of Japan in August 1945. Postwar, the class saw extensive service during the Cold War, with many undergoing the Greater Underwater Propulsion Power Program (GUPPY) conversions to enhance submerged speed and endurance. They participated in numerous exercises with NATO allies and were forward-deployed to key locations like Subic Bay and Holy Loch. Several were transferred to allied navies under programs like the Military Assistance Program, serving with the Italian Navy, Turkish Naval Forces, Hellenic Navy, Republic of China Navy, Pakistan Navy, and Royal Canadian Navy. The last in U.S. service, USS Tigrone (SS-419), was decommissioned in 1975.

Specifications

The Tench-class displaced 1,570 tons on the surface and 2,416 tons submerged, with an overall length of 311 feet 9 inches. Propulsion was provided by four Fairbanks-Morse 38D8-⅛ diesel engines driving electrical generators, which powered two General Electric electric motors on two shafts, yielding a surfaced speed of over 20 knots. Armament consisted of ten 21-inch torpedo tubes (six forward, four aft) with a capacity for 24 Mark 14 or Mark 18 torpedoes, supplemented by a 5-inch/25 caliber deck gun and Bofors 40 mm and Oerlikon 20 mm anti-aircraft guns. The crew complement was 10 officers and 71 enlisted men.

Ships in class

A total of 29 submarines were completed, though 119 were cancelled at the end of World War II. Notable boats include the lead ship USS Tench (SS-417), USS Grenadier (SS-525), USS Tigrone (SS-419), and USS Cutlass (SS-478). Others, like USS Amberjack (SS-522), USS Grampus (SS-523), and USS Pickerel (SS-524), were completed postwar to a slightly modified design. Several, such as USS Trumpetfish (SS-425), were transferred to foreign service, with *Cutlass* remaining in active duty with the Republic of China Navy into the 2020s.

See also

* Gato-class submarine * Balao-class submarine * Greater Underwater Propulsion Power Program * Fleet submarine * Cold War

Category:Submarine classes Category:Fleet submarines of the United States