Permit-class submarine
1961-1996
Immersed 4300-4600 Standard tonnes
84.9 to 89.5 meters
9.8 meters
8.8 meters
143
S5W pressurized water reactor, one propeller
30 knots
4 x 533 -mm torpedo tubes
The Thresher class ( after the sinking of the ship type and Permit class after the second unit ) was a class of nuclear -powered submarines of the United States Navy.
History
Planning and construction
The planning of the Thresher class began in the mid 1950s. Originally the boats were to be built as a cruise missile carrier. However, after the Navy decided in late 1958 under Secretary of the Navy Thomas S. Gates to stop the development of this type in order to direct funds into the programs for submarines with ballistic missiles and aircraft carriers were off the boats of the class hunting submarines. 1960 was the first unit of the stack. 1963 was lost in a testing accident this boat, the USS Thresher (SSN -593 ). Therefore, the construction of some units of the class was considerably delayed, it lay in the later boats up to seven years between keel laying and commissioning. In the first units this margin was three years. The delay was due to the integration of changes, which was decided after the loss of the Thresher in SUBSAFE program.
A total of 14 units were built at Ingalls Shipbuilding three, at New York Shipbuilding, at Electric Boat and at the Portsmouth Naval Shipyard and two on the Mare Iceland Naval Shipyard. The cost was about 55 million U.S. dollars per unit.
Operating time
The successors of the Sturgeon - class entered service in 1967 and made with the permits much of the hunting submarine fleet of the Navy. The boats remained until the early / mid 1990s in service and were replaced by the Los Angeles- and Seawolf - class.
Technology
The hull of the early completed units is 84.9 meters long, the four boats of the late, however, 89.1 and 89.4 meters long, because they had already built improvements from the SUBSAFE program. The repression was so between 4,300 standard tons (ts ) and ts 4600. The hull was made of highly elastic HY -80 steel. This means that the steel has a guaranteed ' yield strength ' ( yield strength ) of 80,000 psi ( pounds per square inch). This corresponds to about 5,516 bar The yield strength ( engl. yield strength ) is a material parameter and refers to that voltage up to which a material under uniaxial tensile stress and moment-free no permanent plastic deformation shows. This is a yield strength. Another advantage of this steel, which is mainly used for shipbuilding, the good weldability.
The nuclear reactor allowed the ship almost unlimited range and a top speed of 30 knots.
The boats of the class had four torpedo tubes with a diameter of 53.3 cm, from which the UUC -44 Subroc, the Mark 48 heavyweight torpedo, the anti-ship missile UGM -84 Harpoon or the cruise missile UGM -109 Tomahawk could be shot down.