The PC-461-class submarine chasers were a class of 341 submarine chasers constructed between 1941 and 1944 for the United States Navy (USN). The PC-461s were based primarily on two experimental submarine chasers, PC-451 and PC-452. While PC-461 began the series, the first of the class to enter service was PC-471. Fifty-nine PC-461s were converted to other types of patrol vessels.
As part of the Lend-Lease program, 41 ships of the class were transferred to allies of the United States. In addition to the USN, six allied navies operated PC-461s during World War II. Postwar, another hundred PC-461s were transferred from the USN to various navies. World events and further transfers from these navies – some ships of the class served in three different navies and one served in four – resulted in another eighteen navies (two of them of adversaries of the US – the Cuban Revolutionary Navy and China's People's Liberation Army Navy) operating PC-461s, with one heavily modified vessel serving in the Peruvian Navy as late as the 2010s. Other ships of the class were sold for civilian use postwar, with a few converted as passenger ships and one converted as a luxury yacht.
Twenty-seven vessels of the class (including three vessels converted to s) were lost during World War II (seven losses), several other later armed conflicts (seven losses) and in peacetime incidents, mostly Pacific Ocean typhoons.
Following World War II, ships of the class were involved in several large and small conflicts from the late 1940s to the 1970s, including the 1948 Arab–Israeli War; the Korean War; the 1961 Bay of Pigs Invasion in Cuba; armed clashes between the Republic of China and the People's Republic of China including the 1954–55 First Taiwan Strait Crisis and the 1965 Battle of Dongshan; the Nigerian Civil War of 1967–1970; and the Vietnam War.
One member of the class, , was one of only two ships in the United States Navy during World War II that had a mostly African-American crew.
Design The PC-461-class submarine chasers were based on two experimental steel-hulled submarine chasers built under the Experimental Small Craft program initiated on 17 May 1938 – PC-451 and PC-452. The keel of PC-451 was laid down on 28 September 1939 by the Defoe Boat and Motor Works in Bay City, Michigan. She was launched on 23 May 1940 and commissioned on 12 August the same year. She displaced 374 tons, was long, had a beam of and had a top speed of 18.8 knots. PC-452 was laid down by Defoe on 14 March 1940 and was launched on 23 August 1941. She was not commissioned until 26 July 1943, having been towed to the Philadelphia Navy Yard after her launch and fitted out with steam turbine propulsion (unlike PC-451, which had diesel engines), consisting of two Beasler boilers supplying a pair of De Laval turbines. Other than the propulsion, PC-452 was closer to the PC-461s than PC-451, having a length of and a beam of , but she had a smaller displacement than PC-451 at 348 tons.
The PC-461-class submarine chasers had the same propulsion as PC-451 and were dimensionally the same as PC-452 (length of and in beam). Each ship had two diesel engines fueled by diesel oil, driving two propellers via a reduction gearbox. Two six-cylinder diesel auxiliary engines were also installed, each driving a 120-volt 500-ampere DC generator. Fuel capacity was 49 tons. Their superstructure was short, ending with a deck for the ships' dinghy amidships, aft of a false funnel (the engine exhaust openings were on the sides of the hull). They were designed to have a draft of , a top speed of 20.2 knots and a crew of four officers and 61 ratings, for a total complement of 65.
Armament Provision was made for two main guns – either the 3-inch/50-caliber (76mm, 3.8m-long barrel) quick-firing dual-purpose gun or the Bofors 40 mm anti-aircraft gun could be fitted, one forward of the superstructure and one aft – and anti-submarine equipment, including a pair of depth charge rails on the stern. The lead ship of the class, USS PC-461, was armed with two 3-inch guns, two 20mm cannon, two M2 Browning .50-caliber machine guns, two M1919 Browning .30 caliber machine guns, two depth charge projectors and the depth charge rails. As World War II progressed, there were several variations in the ships' installed armament, including the addition of a pair of Mousetrap anti-submarine rocket launchers on the bow. For example, , commissioned in December 1942, had two 3-inch guns, five Oerlikon 20 mm cannon, two depth charge projectors, the depth charge rails and the pair of Mousetraps; the armament of USS PC-1145 (commissioned in late October 1943) consisted of one 3-inch gun, one 40mm Bofors gun, three 20mm cannon, four K-gun depth charge projectors, the Mousetraps and the depth charge rails; while (also commissioned in October 1943) had one 3-inch gun, one 40mm Bofors gun, five 20mm cannon and two each of K-guns, Mousetraps and depth charge rails. All ships were fitted with sonar and a radar was installed from late 1942 onwards.
Construction program Several companies were awarded contracts to build the PC-461-class submarine chasers, including Commercial Iron Works – which built 43 ships of the class – and Albina Engine & Machine Works (builder of 21 ships) in Portland, Oregon; the Brown Shipbuilding Company (12 ships) of Houston, Texas; the Consolidated Shipbuilding Corporation (51 ships) of Morris Heights, New York; the Defoe Shipbuilding Company (the renamed Defoe Boat and Motor Works, that had built PC-451 and PC-452 and was the most prolific builder of PC-461s, with 56 completed); Dravo Corporation (15 ships) of Pittsburgh, Pennsylvania, the Gibbs Gas Engine Company (14 ships) of Jacksonville, Florida; the Jeffersonville Boat and Machinery Company (eight ships, seven of which went on to serve with allied navies) of Jeffersonville, Indiana; George Lawley & Son (23 ships) of Neponset, Massachusetts; the Luders Marine Construction Company (22 ships) of Stamford, Connecticut; the Nashville Bridge Company (14 ships) of Nashville, Tennessee; the Penn-Jersey Shipbuilding Company (four ships) of Camden, New Jersey; the Leathem D. Smith Shipbuilding Company (42 ships built) of Sturgeon Bay, Wisconsin; and the Sullivan Drydock and Repair Corporation (16 ships) of Brooklyn, New York.
Just as the ships themselves were constructed by a variety of different companies, the engines were manufactured by several companies including Fairbanks-Morse (38D 8-1/8 engines), General Motors (Cleveland Diesel Engine Division 16-258S and 16-278A engines) and Hooven-Owens-Rentschler (R-99DA engines). The reduction gearboxes were manufactured by Farrel-Birmingham and Westinghouse. The manufacturers of the auxiliary engines included the Buda Engine Company ( six-cylinder inline engines).
USS PC-483 was the first ship to be laid down – on 31 December 1940 (almost a year before the United States entered World War II following the Japanese attack on Pearl Harbor on 7 December 1941) at Consolidated Shipbuilding in Morris Heights, New York. She was launched on 25 October 1941 and commissioned on 12 March 1942. The second and third ships laid down were USS PC-488 (on 7 March 1941) and USS PC-489 (ten days later on 17 March); both were built in New York by the Sullivan Dry Dock and Repair Company. USS PC-471 was the first ship to be completed; laid down on 21 April 1941 at Defoe Shipbuilding in Bay City, Michigan, she was launched on 15 September and commissioned on 3 November. Defoe Shipbuilding also built the second in the class to enter service; , which was laid down on 1 July 1941, launched on 14 November and commissioned two days after Pearl Harbor was attacked (on 9 December 1941). The ship the class was named after, USS PC-461, was the third of the class to be built, being laid down by Lawley & Son at Neponset, Massachusetts on 10 July 1941 and launched on 23 December. By the end of 1941, a fourth ship had been commissioned and another thirteen launched, while 36 more had been laid down.
A total of 341 ships in the class were completed; these were United States Ships PC-461 to , to PC-627, PC-776 to PC-825, PC-1077 to PC-1091, PC-1119 to PC-1149, PC-1167 to PC-1265 and PC-1546 to PC-1569. Contracts for another 60 ships (that were proposed as PC-1092 to PC-1118, to PC-1166 and PC-1570 to PC-1585) were canceled.
The last ship built as a PC-461 was USS PC-1569, which was laid down on 26 September 1944 by Leathem D. Smith Shipbuilding and launched on 9 December. She was commissioned on 14 March 1945 at New Orleans. She served in the USN for less than 18 months, being decommissioned on 9 August 1946 and laid up in the Columbia River Group of the navy's Pacific Reserve Fleet. (She later saw active service again in the Republic of Vietnam Navy, after she was transferred to South Vietnamese ownership in November 1960 and renamed RVNS Van Don.)
Although she was launched on 13 May 1944, USS PC-814 was the last ship of the class to be commissioned, on 5 June 1945.
Conversions Conversions to gunboats Twenty-four PC-461s were converted to patrol gunboats, motor (hull classification symbol PGM). The ships PC-805, PC-806, PC-1088 to PC-1091, PC-1148, PC-1189, PC-1255, PC-1548, PC-1550 to PC-1559 and PC-1565 to PC-1568 were converted to s, some after being commissioned as PC-461-class ships, some after they were launched but before they were commissioned and others being converted during construction. PC-1548 was converted as the lead ship of the class, .
The last of all ships laid down as a PC-461 to be completed was USS PGM-15, which was laid down by George Lawley & Son on 15 June 1945 and launched six-and-a-half weeks later on 31 July, then commissioned on 11 October – almost two months after the announcement of Japan's surrender on 14 August 1945.
Conversions from minesweepers The eighteen s built for the USN were also based on the two experimental submarine chasers PC-451 and PC-452. They differed little from the PC-461s, primarily in having a slightly longer superstructure that surrounded the false funnel and in being fitted with minesweeping equipment instead of the aft gun; all but four also had less-powerful propulsion consisting of two 900 hp Cooper-Bessemer diesel engines, resulting in a speed of 16 knots. These minesweepers were converted to submarine chasers and reclassified as PC-1586 to PC-1603.
World War II service + PC-461-class successes in World War II Ship DateDetailsLocation 30 Jul. '42 Sank German submarine Gulf of Mexico 2 Jun. '43 Sank German submarine Atlantic Ocean off the Eastern Shore of Virginia, USA 10 Jun. '43 Sank Japanese submarine I-24 Bering SeaUSS PC-543 10 Jul. '43 Shot down two bombers during invasion of SicilyNear Gela, Sicily 30 Jul. '43 Sank German submarine Mediterranean Sea near the island of PantelleriaUSS PC-1135 19 Mar. '44 Participated in attack that sank Japanese submarine I-32 Pacific Ocean south of Wotje AtollUSS PC-545 24 Mar. '44 Sank a German E-boat Tyrrhenian Sea near Anzio, ItalyUSS PC-619 17 Apr. '44 Participated in attack that sank German submarine North Atlantic Ocean southwest of Ireland9 May '44Sank a German Neger one-man torpedo-carrying craft; shared with USS PC-626 in sinking of another Off the coast of ItalyUSS PC-6269 May '44Shared with USS PC-558 in sinking of a Neger Off the coast of ItalyUSS PC-62714 May '44Sank an Italian torpedo boat Off Anzio, ItalyUSS PC-619 10 Jun. '44 Shot down a German bomberBaie de Seine, off the Normandy invasion beachhead23-25 Oct. '44Shot down three Japanese aircraftOff the coast of Leyte, Philippines