which necessitated additional repairs at Charleston, South Carolina. On 9 October, she passed her sea trials and sailed to Key West, Florida, for two weeks of torpedo tube tests and a wire-guided torpedo development project. Shark returned to Norfolk on 25 October 1965 and conducted type training, individual ship exercises, and antisubmarine warfare exercises until 8 January 1966. The boat then operated in the Caribbean until 7 February. She was there again for further trials in July and October. Shark stood out of Norfolk on 7 January 1967 for the North Atlantic and conducted special operations until 24 March. Two weeks of this period were spent at Holy Loch, Scotland. On 12 April, she was presented her second Navy Unit Commendation for operations in 1966 in which "Shark contributed significantly to the knowledge of the United States Navy in the field of antisubmarine warfare." Shark departed Norfolk on 16 May for Halifax, Nova Scotia, which was the first visit of a nuclear ship to a Canadian port. The submarine operated with Royal Canadian Navy ASW units before returning to her home port. In 1967 Shark was used in a Naval Department educational film for training and public relations. On 11 June 1967, Shark prepared for her first refueling period at the Norfolk Naval Shipyard and did not put to sea again until March 1968. The remainder of 1968 and 1969 was spent performing local or special operations. 1970s Shark was in drydock at Norfolk from 1 January 1970 to 9 August 1971. The remainder of the year and 1972 was spent in refresher training and undergoing various trials along the East Coast, with the exception of a deployment to the Sixth Fleet from 31 May to 19 November 1972. Mare Island Naval Shipyard for overhaul September 1981 to May 1983. Returned to New London Connecticut. History from 1972 to 1986 needed. She would take part in another deployment with the Atlantic Fleet in 1974 before returning to Pascagoula for a reactor refueling in August. This refueling and overhaul would take more than two years. When Shark returned to the ocean, her home port was changed to New London, Connecticut. In 1978, Shark had a busy schedule, taking part in UNITAS exercises with a number of South American navies and deploying to Mediterranean as part of the Sixth Fleet. In 1980, Shark took part in exercises with the Atlantic Fleet and