SS-342 USS Chopper

Name: USS Chopper (SS/AGSS/IXSS-342)
Namesake. Chopper, a common name for Pomatomus saltatrix, an aggressive game fish.
Builder: Electric Boat Company, Groton, CT
Laid down: 2 Mar 1944
Launched: 4 Feb 1945
Commissioned: 25 May 1945
Decommissioned: 27 Aug 1969
Struck: 1 Oct 1971
Fate: Sunk off Cape Hatteras, 21 Jul 1976, while being rigged as a tethered underwater target
Class and type: Balao-class diesel-electric submarine
Displacement.
1,529 long tons (1,554 t) surfaced
2,424 long tons (2,463 t) submerged
Length. 311 ft 9 in (95.02 m)
Beam. 27 ft 3 in (8.31 m)
Draft. 16 ft 10 in (5.13 m) maximum
Propulsion.
4 × General Motors Model 16-278A V16 diesel engines driving electrical generators
2 × 126-cell Sargo batteries
4 × high-speed General Electric electric motors with reduction gears
2 × propellers
5,400 shp (4.0 MW) surfaced
2,740 shp (2.0 MW) submerged
Speed. 20.25 kn (23.30 mph; 37.50 km/h) surfaced, 8.75 kn (10.07 mph; 16.21 km/h) submerged
Range. 11,000 nmi (13,000 mi; 20,000 km) surfaced at 10 kn (12 mph; 19 km/h)
Endurance. 48 hours at 2 kn (2.3 mph; 3.7 km/h) submerged, 75 days on patrol
Test depth. 400 ft (120 m)[3]
Complement. 10 officers, 70–71 enlisted
Armament.
10 × 21-inch (533 mm) torpedo tubes, 6 forward, 4 aft
24 torpedoes
1 × 5-inch (127 mm) / 25 caliber deck gun
Bofors 40 mm and Oerlikon 20 mm cannon

General characteristics (Guppy IA)
Displacement.
1,830 long tons (1,860 t) surfaced
2,440 long tons (2,480 t) submerged
Length. 307 ft 7 in (93.75 m)
Beam. 27 ft 4 in (8.33 m)
Draft. 17 ft (5.2 m)
Propulsion.
Batteries upgraded to Sargo II
Speed. Surfaced: 17.3 kn (19.9 mph; 32.0 km/h) maximum, 12.5 kn (14.4 mph; 23.2 km/h) cruising
Submerged: 15.0 kn (17.3 mph; 27.8 km/h) for ½ hour, 7.5 kn (8.6 mph; 13.9 km/h) snorkeling, 3.0 kn (3.5 mph; 5.6 km/h) cruising
Range 17,000 nmi (20,000 mi; 31,000 km) surfaced at 11 kn (13 mph; 20 km/h)
Endurance. 36 hours at 3 kn (3.5 mph; 5.6 km/h) submerged
Complement. 10 officers, 5 petty officers, 64–69 enlisted men
Armament.
10 × 21 inch (533 mm) torpedo tubes (six forward, four aft)
all guns removed
Snorkel added