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. Two weeks of this period were spent at Holy Loch, Scotland. Shark stood out of Norfolk on 7 January 1967 for the North Atlantic and conducted special operations until 24 March. She was there again for further trials in July and October. The boat then operated in the Caribbean until 7 February. Shark returned to Norfolk on 25 October 1965 and conducted type training, individual ship exercises, and antisubmarine warfare exercises until 8 January 1966. 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. One month later, she suffered damage to the forward oxygen system which necessitated additional repairs at Charleston, South Carolina. The submarine put to sea for sea trials on 7 June. On 7 April 1965, at the shipyard, Shark was presented the Navy Unit Commendation for meritorious service from 5 April to, a period in which she 'achieved results of great value and importance to the United States Navy in the field of antisubmarine warfare capabilities.' On 25 June 1964, she sailed to Charleston, South Carolina, for her first shipyard overhaul which lasted until 7 June 1965. On 22 March 1964, Shark departed Norfolk to participate in SUBSPRINGEX and returned on 21 May. The remainder of 1963 was either spent in port, in local operations, or conducting antisubmarine warfare exercises in the Caribbean. Shark participated in SUBFALLEX in the North Atlantic from 7 August to 24 October, with a week spent in Faslane, Scotland. On her return trip to Norfolk, Virginia, she underwent an availability period that lasted until 7 January 1963. On 25 August, she departed for another two months in the North Atlantic. During this period, Shark paid a one-week visit to Portsmouth, England. She was next deployed to the North Atlantic from 15 March to 23 May. On 29 January 1962, the submarine steamed to Bermuda in the British West Indies, for two weeks of type training. This was the first such deployment for a nuclear submarine, and Shark was deployed until 14 November 1961. Shark sailed for the Mediterranean Sea and duty with the Sixth Fleet on 12 August.

Submarine shark