USS Segundo ( SS - 398 ) USS " Segundo " ( SS - 398 ) , a " Balao " - class submarine , was a ship of the United States Navy named for the segundo , a cavalla fish of Caribbean waters . " Segundo " was laid down on 14 October 1943 by the Portsmouth Navy Yard in Kittery , Maine ; launched on 5 February 1944 ; sponsored by Mrs . John L . Sullivan ; and commissioned on 9 May 1944 , Lieutenant Commander James D . Fulp , Jr . , in command . " Segundo " completed fitting out and contract trials then moved to New London , Conn . , on 15 June and began training . The submarine stood out of New London on 26 June for the Panama Canal Zone en route to the Pacific war zone . She departed Balboa on 9 July and arrived at Pearl Harbor on 25 July . The next several weeks were spent in training exercises and weapons firing . The ship was combat loaded on 19 August and 20 August and , the next day , sailed on her first war patrol . First and second patrols , August 1944 – January 1945 . " Segundo " , together with submarines , and formed a wolf pack . They refueled at Saipan on 3 September and departed the next day for their patrol area in the Philippines near Surigao Strait . No worthwhile targets were found , and " Segundo " ended her patrol at Majuro Atoll , Marshall Islands , on 21 October without having fired a shot . The second patrol , from 16 November 1944 to 5 January 1945 , was more profitable . " Segundo " , and sister ships , and were cruising between Luzon Strait and the South China Sea . On the evening of 6 December , a convoy of seven escorted merchant ships was sighted . The three submarines made night attacks which sank all of the merchantmen . Third patrol , February – March 1945 . " Segundo " refitted at Guam from submarine tender and was in the East China Sea with " Razorback " and on 1 February . Three torpedo attacks were made on unescorted ships near the Korean coast in shallow water . The first attack was on 6 March against a small ship but all torpedoes missed . The next was made four days later against a medium - sized ship . Four torpedoes were fired at but they also missed . The third attack was a night surface action against a cargo ship on 11 March . Two torpedoes of the spread hit . The first blew the stern off and the second hit amidships , sinking cargo ship " Shori Maru " in two minutes . The submarine ended her patrol at Pearl Harbor on 26 March and remained there for a month before putting to sea again . Fourth and fifth patrols , May – August 1945 . " Segundo " was assigned to a lifeguard station until 16 May when she departed for her assigned area in the East China Sea . On 29 May , she sank seven two - masted schooner s of approximately 100 tons each with shellfire . Two days later , she sank a large four - masted full - rigged ship of approximately 1 , 250 tons with two torpedoes . She sank another on 3 June with her deck gun . On 9 June , two patrol ships were also sunk by her deck gun . On the night of 11 June , the " Fukui Maru " was torpedoed and sunk . The submarine then sailed to Midway Atoll for upkeep . " Segundo " began her fifth and final war patrol on 10 August in the Sea of Okhotsk . Ordered to proceed to Tokyo Bay on 24 August , the ship was proceeding south when she picked up a Japan ese Sen Toku class I - 401 submarine , which was at the time the largest submarine in the world , by radar on 29 August . The enemy boat was ordered to halt by international signal . This was done ; and , after several trips between the two submarines by their respective representatives , the Japanese agreed to accept a prize crew aboard and to proceed to Tokyo with " Segundo " . The two ships entered Sagami Wan on 31 August and , at 05 : 00 , the American flag was raised aboard the " I - 401 " . 1945 – 1953 . " Segundo " stood out of Tokyo Bay on 3 September 1945 en route to the west coast via Pearl Harbor . She was assigned to SubRon 3 in San Diego and began operations from there . The submarine made a three - month cruise to Australia and China in 1946 and a four - month cruise to China in 1948 . The outbreak of the Korean War found " Segundo " in the Far East . She supported United Nations Forces in Korea from July to September 1950 before returning to San Diego in late November . In 1951 , " Segundo " was modernized and converted to a Fleet Snorkel submarine at the San Francisco Naval Shipyard . She returned to her home port and resumed operations until 15 August 1952 when she again joined the 7th Fleet off Korea . That deployment period ended on 16 February 1953 . 1953 – 1970 . For the next 16 years , " Segundo " operated out of her home port and along the west coast . From 1953 through 1969 , she was deployed to the western Pacific every year except 1956 , 1957 , 1961 , and 1963 . per ship log - key dates in history Segundo departed for the Western Pacific Ocean on Nov 27 1956 with stops in Pearl Harbor , Hi . , Yokosuka , Japan , Hong Kong , China , Subic Bay and Manila , Phillipines and Buckner Bay , Okinawa . In July 1970 , a Survey Board found " Segundo " unfit for further Naval service . The submarine was decommissioned 1 August , and struck from the Navy list on 8 August 1970 and sunk as a target by the submarine . Honors and awards . " Segundo " received four battle star s for World War II service and one for the Korean War .