She wound up the year with another visit to Guantanamo Bay. During the 1967 North Atlantic NATO operation "Quick Pursuit," "Picuda" lost two men at sea (Lieutenant (junior grade) Jerry R. Alexander and Chief Torpedomans Mate Robert E. Small). She visited Bergen, Norway and Portsmouth, England before returning to Key West. At the time of her decommissioning, "Picuda" held the record for being the longest serving submarine in the history of the US Navy. She had served 28 years, 11 months and 15 days. The previous record holder was USS "O-4" (SS-65). Transferred to Spain on 1 October 1972, former "Picuda" was renamed . The submarine was stricken from the U.S. Navys Naval Vessel Register on 1 November 1974 and was purchased outright by Spain on 18 November 1974. In 1975, she was laid up with mechanical defects and finally deleted from the "Armada Española" on 30 April 1977, her name being shifted to former ex-"Jallao" (SS-368), which the Spanish had acquired.