Balao -class submarine
The Balao-class submarine was a class of diesel-electric fleet submarines developed and constructed for the United States Navy during World War II, serving as an evolutionary improvement over the earlier Gato-class with enhanced hull strength for greater diving capability.[1] Featuring a pressure hull made of high-tensile steel approximately 7/8 inch (22 mm) thick, these submarines had a designed test depth of 400 feet—100 feet deeper than the Gato-class—to better withstand depth charge attacks and operate in contested waters.[1] With a surfaced displacement of approximately 1,525 tons and a submerged displacement of 2,424 tons, each boat measured 311 feet 9 inches in length, with a beam of 27 feet 3 inches and a surfaced draft of about 15 feet.[1] Armed with ten 21-inch torpedo tubes—six forward and four aft—the Balao-class carried up to 24 torpedoes, supplemented by a 5-inch deck gun, 40 mm and 20 mm antiaircraft guns, and provisions for minesweeping or other specialized roles.[1] Powered by four diesel engines and four electric motors, they achieved a maximum surfaced speed of 20.25 knots and a submerged speed of 8.75 knots, with a cruising range of 11,000 nautical miles at 10 knots surfaced, enabling extended patrols across the vast Pacific Ocean.[1] The crew complement numbered around 80 officers and enlisted men, operating in harsh conditions that demanded high reliability and endurance.[2] A total of 120 Balao-class submarines were completed between 1943 and 1948, making it the largest submarine class in U.S. Navy history and forming the backbone of the submarine force alongside the Gato- and Tench-classes, with 108 serving during World War II.[3] The lead ship, USS Balao (SS-285), was commissioned on 4 February 1943, with production distributed among major shipyards including Electric Boat, Manitowoc, and Portsmouth Naval Shipyard to meet wartime demands.[4] Many were built using modular construction techniques to accelerate output, reflecting the Navy's urgent need for undersea assets following the attack on Pearl Harbor.[5] In the Pacific Theater, U.S. submarines, including the Balao-class, accounted for over half of all Japanese shipping sunk during the war, with the Balao-class responsible for more vessel sinkings overall than any other U.S. Navy class.[5] They disrupted vital supply lines, supported island-hopping campaigns, and rescued downed aviators, with notable exploits including the sinking of heavy cruisers and aircraft carriers despite the hazards of enemy antisubmarine warfare.[3] Postwar, survivors were converted for various roles, including guided-missile submarines and radar pickets, before most were decommissioned by the 1970s as nuclear-powered vessels entered service.[6]Design
Specifications
The Balao-class submarines represented an evolutionary improvement over the preceding Gato-class, incorporating a strengthened pressure hull constructed from higher-tensile steel to enhance diving capabilities while maintaining similar overall dimensions and performance metrics.[7] This design allowed for greater operational depth without significantly altering displacement or speed, prioritizing reliability and crew survivability in combat environments.[8] Key physical and performance specifications of the Balao-class as originally designed are summarized below:| Category | Specification |
|---|---|
| Displacement | 1,525 long tons (1,550 t) surfaced; 2,415 long tons (2,453 t) submerged |
| Dimensions | Length: 311 ft 9 in (95.0 m); beam: 27 ft 3 in (8.3 m); draft: 16 ft 10 in (5.1 m) |
| Speed | 20.25 knots (37.5 km/h; 23.3 mph) surfaced; 8.75 knots (16.2 km/h; 10.1 mph) submerged |
| Range | 11,000 nautical miles (20,000 km; 12,000 mi) at 10 knots (19 km/h; 12 mph) surfaced |
| Crew | 80 (10 officers, 70 enlisted) |
| Test depth | 400 ft (120 m) |