USS Besugo (SS-321, later AGSS-321), a Balao-class submarine, was a ship of the United States Navy in commission from 1944 to 1958. She was named for the besugo.
During World War II, Besugo made five war patrols between 26 September 1944 and 25 July 1945, operating in the Bungo Channel, Makassar Strait, Java Sea, and South China Sea. During these patrols, Besugo sank the German submarine , becoming one of a very few U.S. submarines to sink a German naval vessel during the war. She also sank the 10,020-gross register ton tanker Nichei Maru, one landing ship, one frigate, and a minesweeper.
After post-World War II Korean War and Cold War U.S. Navy service, Besugo was decommissioned. She was loaned to the Italian Navy in 1966, in which she served until 1973 as Francesco Morosini (S 508).
Construction and commissioning Besugo′s keel was laid down on 27 May 1943 at Groton, Connecticut, by the Electric Boat Company. She was launched on 27 February 1944, sponsored by Mrs. Margaret Perry Homer, an employee in the Outside Machinist's Department of the Electric Boat Company and wife of Peter J. Homer, also an employee of the company. Besugo was commissioned at Naval Submarine Base New London in Groton on 19 June 1944 with Commander Thomas L. Wogan in command.
Service history United States Navy World War II June–September 1944 Besugo completed shakedown training in the waters off New London, Connecticut, before heading south on 25 July 1944. Arriving at Key West, Florida, on 1 August 1944, she conducted another two weeks of training with the Key West Sound School before setting out for the Pacific Ocean on 13 August. She transited the Panama Canal on 17 August and, after five days of repairs at Balboa in the Panama Canal Zone, continued on to Pearl Harbor in the Territory of Hawaii, arriving there on 7 September 1944. She spent the next two weeks training in the waters of the Hawaiian Islands.
First war patrol
Besugo put to sea from Pearl Harbor for her first war patrol on 26 September 1944, escorted until dark by the submarine chaser . In company with the submarine , Besugo headed west and stopped at Midway Atoll in the Northwestern Hawaiian Islands to refuel on 30 September. Departing Midway the same day, the two submarines rendezvoused with the submarine before heading northwest to the Bungo Channel entrance to Japan's Seto Inland Sea.
While en route on 6 October 1944, the submarines spotted a picket boat — a small Japanese patrol boat — lying to northwest of Marcus Island. As Besugo closed to destroy the patrol boat, Gabilan and Ronquil continued on course. At 21:02, Besugo fired three torpedoes at the target. All missed, probably because of the shallow draft of the patrol boat. After waiting for night to fall, Besugo circled the target, surfaced, and closed for a gun attack at 22:28. Although the combination of light swells and insufficient moonlight made gunfire ineffective, the two 20-millimeter guns scored some hits. The Japanese patrol boat responded with sporadic bursts of light machine-gun fire. Just as the patrol boat closed the range, both of Besugo′s 20-millimeter guns jammed. The Japanese picket boat then opened fire with a heavy machine gun. Bullets began striking the water around Besugo, and several struck her conning tower and periscope shears. Splinters from these hits wounded the gunnery officer and a lookout. Unable to return fire effectively, Besugo withdrew, leading her commanding officer to remark, "Not an auspicious beginning to our fighting career."
On 8 October 1944, Besugo spotted an Imperial Japanese Navy Mitsubishi G4M Type 1 bomber (Allied reporting name "Betty") and submerged for the remainder of the day. On the morning of 9 October, a patrolling Japanese armed trawler forced her to submerge, further delaying her progress. Then, at 03:29 on 10 October, her radar indicated a Japanese patrol plane was pursuing her. As put by her war diarist, it took half an hour of "nerve-wracking" maneuvering to shake off the Japanese plane.
At dawn on 10 October 1944, Besugo reached her patrol station and began a submerged daylight patrol in the eastern approaches to the Bungo Channel. Owing to the upcoming U.S. landings on Leyte in the Philippine Islands, scheduled for 20 October, Besugo had orders to spot any Japanese heavy fleet units departing the Bungo Channel and to refrain from firing at any targets until after sending in a contact report. On the morning of 15 October 1944, she watched as five Japanese cruisers and a destroyer steamed by her position before she radioed in a contact report that evening.
On the evening of 16 October 1944, Besugo′s radar picked up two targets transiting the Bungo Channel. Believing they were heavy cruisers, Besugo maneuvered into firing position and loosed six bow torpedoes at the nearest target. Two minutes later, at 22:12, one torpedo hit one of the Japanese warships just abaft the bridge. The Japanese ships "milled about," according to Besugo′s war diary, for a few minutes, during which time Besugo retired to reload, but the Japanese quickly skirted the coast of Kyushu and turned for home. Besugo tracked them for almost two hours but was unable to close for another attack. A postwar review of records indicated that the damaged ship actually was the destroyer .
On 18 October 1944, Besugo spotted two more warships, this time entering the Bungo Channel rather than leaving it, and noted the contacts in accordance with her orders. Although Japanese air patrols increased noticeably over the next few days, including one radar-equipped search plane that kept Besugo pinned down on 22 October, Besugo and Ronquil did manage to find a Japanese formation early on 24 October 1944. At 03:49 that morning, Besugo closed a Japanese tanker, protected by two coast defense frigates and a destroyer, intending to sneak between two of the escorts for a shot at the tanker. However, two rapid Japanese zigzags away put the tanker out of reach, so Besugo turned on the port-quarter escort instead. She fired three torpedoes at the escort, the frigate Coast Defense Vessel No. 132, and, at 04:15, at least one torpedo hit the target. In a blinding flash, the frigate suddenly blew up, illuminating the entire area and silhouetting Besugo on the surface. She crash-dived, expecting to be depth-charged by the rear escort, but no counterattack attack materialized.
Over the next week, Besugo and up to six other U.S. submarines patrolled the approaches to Van Diemen Strait (also known as Ōsumi Strait) and the east coast of Kyushu, hoping to catch some of the Japanese warships retiring north from their defeat in the waters around the Philippine Islands in the Battle of Leyte Gulf. The only things Besugo spotted were three Japanese patrol planes, a Japanese submarine′s periscope, and a drifting contact mine, all of which she evaded with some difficulty. Retiring to the Mariana Islands on 1 November 1944, Besugo concluded her patrol by mooring alongside the submarine tender at Saipan on 5 November 1944.
Second war patrol Following minor repairs and a torpedo reload, Besugo departed Tanapag Harbor at Saipan to begin her second war patrol on 10 November 1944. Transiting the Luzon Strait on 16 November 1944, she entered the South China Sea, and she took up a position off Linapacan Island in the Philippine Islands on 20 November. At 04:55 on 22 November, Besugo picked up a radar contact while operating off the northern tip of Palawan. Owing to the approaching dawn, she attacked the target quickly, firing four torpedoes at what she believed was a Japanese tanker. One torpedo hit amidships, starting an enormous fire that eventually sank what turned out to be the Japanese landing ship T.151. A few minutes later, she spotted a barge nearby, probably a tow abandoned by the stricken landing ship, and sank it with two torpedoes.
Returning to her patrol station that evening, Besugo encountered rough weather, and the heavy swells interfered with her surface search radar. At 21:38, she closed her only good contact and fired four bow torpedoes at a large vessel. All missed, possibly because they grounded in the shallow water. Over the next 10 minutes, she fired eight more torpedoes, one of which finally hit and brought to a stop what turned out to be a cargo ship. Besugo then fired her last four torpedoes into the target. Two of them demolished the midships section and the ship settled to the bottom in of water, leaving the superstructure still visible above the surface. A postwar records review, however, did not indicate any Japanese losses in that area, and Besugo did not receive credit for a sinking. With her torpedoes gone, Besugo headed south, passed through the Lombok Strait, and arrived at Fremantle, Australia, on 4 December 1944, bringing her patrol to an end.
Third war patrol After a refit alongside the submarine tender , Besugo got underway for her third war patrol on 24 December 1944. She passed through Lombok Strait late on 30 December and entered the Celebes Sea. On 31 December 1944 she sighted a small Japanese merchant ship emerging from a rain squall. Besugo dove and attacked with three torpedoes, but all missed, and the target escaped and disappeared from view. It probably radioed in a contact report, because searching Japanese aircraft later forced Besugo to submerge four times.
Clearing Karimata Strait on 2 January 1945, Besugo took up a patrol station off the southern tip of Japanese-occupied French Indochina on 4 January. At 18:40 on 6 January, her lookouts sighted the heavily laden Japanese 10,020-gross register ton tanker Nichei Maru escorted by a destroyer and two coast defense frigates. She closed undetected and at 21:18 fired six torpedoes at Nichei Maru. Three of the torpedoes hit home, and Nichei Maru burst into flame and sank. As Besugo cleared the area, the escorts dropped seven depth charges in desultory and ineffective attacks.
Joined by the submarines , , and later , Besugo spent the next two weeks fruitlessly patrolling a scouting line south of the Cà Mau Peninsula. Finally, at 05:30 on 24 January 1945, she received a contact report from Blackfin. As Besugo closed the three Japanese ships (destroyer , the tanker Sarawak Maru, and a small minesweeper) Blackfin reported, her crew heard Blackfin send one torpedo into the tanker. Shortly thereafter, the Japanese escorts drove Besugo off with gunfire and depth charges. Twenty minutes later, Besugo tried approaching again and, despite sonar searches and a close depth-charge attack by the escorts, she fired six torpedoes at the tanker. The torpedo tracks attracted the attention of the escorts, and Besugo endured a furious pounding from the two escorts, who dropped a total of 22 depth charges over the next half hour. Later that afternoon, Besugo′s crew heard Japanese escorts drop another 32 depth charges. A postwar records review determined the tanker to have been damaged in the attack.
A week later, Besugo discovered four Japanese antisubmarine warfare vessels conducting a sound sweep off Cape Laguan on the Malay Peninsula. After calling in Blackfin and Hardhead for help, Besugo crept under the right-flank ship and took up a firing position. At 02:27 on 2 February 1945, she fired four torpedoes at the right-center ship, and one of them hit and sank the frigate Coast Defense Vessel No. 144. Besugo easily evaded the ensuing counterattack and withdrew from the area. As no further contacts developed, she set a course for Australia on 5 February 1945, transited Lombok Strait on 8 February, and moored alongside the submarine tender in the harbor at Fremantle on 15 February 1945.
Fourth war patrol