With the loss of USS Thresher (SSN-593) during a deep sea trials on April 10th, 1963, the United States Navy (USN) retired the "Thresher" name in remembrance and revised the Thresher-class to become the Permit-class after the second boat in the group. USS Permit (SSN-594) was ordered on January 27th, 1958 and built by the Mare Island Naval Shipyard in Vallejo, California. Her keel was laid down on May 1st, 1959 and she was launched to sea on July 1st, 1961. The boat was formally commissioned for service on May 29th, 1962.
USS Permit Walk-Around
USS Permit typically carried a crew of 105 and had a displacement of 3,760 tons (short) when surfaced and 4,370 tons when submerged. Dimensions included an overall length of 278.4 feet, a beam of 31.6 feet and a draught of 25.1 feet. Power was from a single S5W (Submarine, 5th Gen, Westinghouse) nuclear reactor tied to 2 x geared steam turbines developing 15,000 horsepower to a single shaft astern. 15 knots were attainable when surface running and nearly 30 knots could be reached when submerged. The hull was tested to a depth of 1,300 feet. Armament was 4 x 21" (533mm) torpedo tubes fitted amidships.
The Thresher-class was an important addition to the USN during this part of the Cold War period. The type was designed with noise reduction qualities to make her more resistant to sonar detection and the nuclear powerpack gave them essentially unlimited range under water - restricted mainly by crew fatigue and onboard food stores. The boats were also fast and appropriately armed for the purpose of engaging enemy forces on the sea and under it. The group served for some three decades and were succeeded by the Sturgeon-class.
On March 28th, 1963, USS Permit became the first USN submarine to successfully fire the in-development SUBROC missile and was used in testing the weapon at length. When USS Thresher was tragically lost in April of 1963, USS Permit stood up to take the lead of the Thresher-class - now renamed to Permit-class. An overhaul greeted her career during late 1966 and in May of the following year she joined with WESTPAC in the Pacific Theater before returning stateside to the American West Coast. The boat was given another overhaul in 1967 before returning to active service in the Pacific.
USS Permit was decommissioned on July 23rd, 1991 after several decades of faithful service and her name was struck from the Naval Register soon after. With her nuclear powerpack properly disposed of and her hull stripped of its military usefulness, the boat was sold off for scrap, bringing about her official end on September 30th, 1991.