Trigger 1952
Tang 1963
Wahoo 1974
Gudgeon 1979
| No | Name | Yard No | Builder | Laid down | Launched | Comm | Fate |
| SS563 | Tang | Portsmouth N Yd, Kittery | 18.4.1949 | 19.6.1951 | 25.10.1951 | to Turkey 2.1980 (Piri Reis) | |
| SS564 | Trigger | 131 | Electric Boat, Groton | 24.2.1949 | 14.6.1951 | 31.3.1952 | to Italy 7.1973 (Livio Piomarta) |
| SS565 | Wahoo | Portsmouth N Yd, Kittery | 24.10.1949 | 16.10.1951 | 30.5.1952 | stricken 7.1983 | |
| SS566 | Trout | 134 | Electric Boat, Groton | 1.12.1949 | 21.8.1951 | 27.6.1952 | to Iran 12.1978 (کوسه [Kousseh]) |
| SS567, 4.1979- AGSS567, 11.1979- SSAG567 | Gudgeon | Portsmouth N Yd, Kittery | 20.5.1950 | 11.6.1952 | 21.11.1952 | to Turkey 9.1983 (Hızır Reis) | |
| SS568 | Harder | 135 | Electric Boat, Groton | 30.6.1950 | 3.12.1951 | 19.8.1952 | to Italy 2.1974 (Romeo Romei) |
|
Displacement standard, t |
|
|
Displacement normal, t |
SS563 - 566: 1560 / 2260 SS567, 568: 1821 / 2500 |
|
Length, m |
SS563 - 566: 82.0 SS567, 568: 84.8 |
|
Breadth, m |
8.30 |
|
Draught, m |
5.20 |
|
No of shafts |
2 |
|
Machinery |
SS563 - 566: 3 General Motors diesel-generators, 2 electric motors SS567, 568: 3 Fairbank Morse diesel-generators, 2 electric motors |
|
Power, h. p. |
SS563 - 566: 3400 / 4700 SS567, 568: 4500 / 5600 |
|
Max speed, kts |
SS563 - 566: 15.5 / 18.3 SS567, 568: 15.5 / 16 |
|
Fuel, t |
diesel oil |
| Endurance, nm(kts) | 11500(10) / 130 (3) |
|
Armament |
8 - 533 TT (6 bow Mk 43, 2 stern Mk 44, 26 torpedoes or 40 mines) |
|
Electronic equipment |
BPS-12 radar, BQS-4, BQR-2 sonars, APR-1 ECM suite |
|
Complement |
83 |
|
Diving depth operational, m |
210 |
Project history: These ships, the US counterpart of the Soviet 'Whiskeys', were the US attempt to assimilate German Type XXI concepts. The first four also had a new compact radial ('pancake') diesels, which itself caused considerable problems in service, the first four units being lengthened and re-engined with the more conventional power plants of the last pair. Originally conceived almost as an experimental high-speed type (in contrast to the usual fleet boat), they became the basis for postwar development. Compared to wartime fleet submarines, they had much increased battery power for greater submerged speed. Compared to the GUPPY conversions, they benefited from a shorter hull form which in itself reduced resistance underwater. They also had streamlined superstructures, and improved sonars, although by no means in the SSK category; the new hull form reduced the torpedo tube battery to eight, with only two aft.
They were two competitive designs, SS563 by Portsmouth Naval Shipyard and SS564 by Electric Boat, both to the same basic characteristics. The initial Ship Characteristics Board requirements included the the potential for re-engining with a closed cycle or nuclear power plant for an underwater speed of 25kts (17kts with a diesel-electric plant), and an increase in diving depth from the wartime 120m to 210m postwar.
Modernizations: early 1950s, Tang, Trigger, Wahoo, Trout: were lengthened and re-engined with data as SS567, 568 (1800/2500t, 84.8m oa, 4500/5600hp, 15.5/16kts)
1950s, all: - APR-1 ECM suite; + BLR-1 ECM suite
1964, Wahoo; 1967, Gudgeon: lengthened (2050/2700t, 87.5m); + BQG-4 PUFFS sonar
Naval service: No significant events.
Wahoo 1968
© Ivan Gogin, 2015