The Barnegat class was a large class of United States Navy small seaplane tenders (AVP) built during World War II. Thirty were completed as seaplane tenders, four as motor torpedo boat tenders, and one as a catapult training ship.Conway's All the World's Fighting Ships 1922–1946, p. 157

Design After relying on improvised and converted vessels to support seaplanes through most of the interwar period, in the five years before the Attack on Pearl Harbor the United States Navy received long-sought funding for the construction of two types of new-build seaplane tenders to support the operation of flying boats attached to Patrol (VP) Squadrons from undeveloped islands and atolls. Full-size seaplane tenders (AVs) were designed to support two squadrons each, but they were more expensive to build and had a deep draft, precluding their use in shallow harbors. The U.S. Navy therefore also ordered a sizable number (41) of "small seaplane tenders" (AVPs), the Barnegat class, with a shallower draft, capable of supporting only one squadron each, but cheaper to build and able to operate in shallow waters. Both the full-size and small seaplane tenders were designed to provide supplies, spare parts, fuel, repairs, and berthing for assigned seaplane squadrons, and were well-armed so that they could serve as the primary line of defense of the seaplane bases they set up.

The Barnegat-class ships were the first (and only) purpose-built AVPs, prior ships carrying that designation having been Lapwing-class minesweepers pressed into service as tenders from 1918 onward. They were preceded into service by 14 "Seaplane Tenders (Destroyer)" (AVDs), interim vessels converted from old destroyers because, with war imminent, completion of enough Barnegats to meet pressing needs could not be guaranteed.

The Barnegat design was derived from those of two other recent classes of ship: the two-strong Erie class of gunboats, and the seven-strong Treasury-class of Coast Guard cutters, all built in 1936-1937. The Barnegats were reliable, long-ranged, and seaworthy, and had good habitability, having been built with berthing capacity for an entire flying-boat squadron's aircrews. They were also well-armed, equipped with between one and four 5-inch (127-millimeter) 38-caliber dual-purpose main guns, as well as varying numbers of 20 mm and 40 mm antiaircraft guns, and depth charge racks and sonar for antisubmarine work. The armament was reduced after the war; those ships in commission as survey ships were entirely unarmed by 1959.

The ships' size and armament enabled them to take on numerous assignments other than their intended ones, including convoy escort, shore bombardment, tanking, and troop and cargo transport duties. Nonetheless, in the spring of 1943, the U.S. Navy concluded that the number of Barnegats ordered was excess to requirements. Four of them were therefore converted during construction into motor torpedo boat tenders, while a fifth was modified during construction for use as a catapult training ship for battleship and cruiser floatplane pilots, her catapult equipment coming from that manufactured for canceled Cleveland-class light cruisers. Six other Barnegats were canceled—four on 22 April 1943 and two more on 29 April 1943 – without having been laid down, their diesel engines being needed for various escort ships and amphibious landing craft.

Three Barnegats were selected in 1945 for conversion to press information ships in anticipation of the 1945–1946 invasion of Japan, but when the war ended without this invasion being necessary they were converted back into seaplane tenders.

Naming The class was named for its lead unit, Barnegat. A few of the ships were named after islands, but the vast majority were named after bodies of water, mostly bays, sounds, and inlets, around the United States and the then-Territory of Alaska.

Post-War Careers The ships entered service between 1941 and 1946, and all but three of them were commissioned in time to participate in combat actions in World War II. The motor torpedo boat tenders served in the Pacific during the latter half of the war, while the seaplane tenders saw service in virtually every theater in which the United States Navy operated during the war.See the various ship articles in the Dictionary of American Naval Fighting Ships at https://www.history.navy.mil/research/histories/ship-histories/danfs.html and at NavSource Small Seaplane Tenders (AVP) at http://www.navsource.net/archives/09/43/43idx.htm.

The combination of the post-World War II downsizing of the U.S. Navy and the decline of the seaplane and motor torpedo boat in U.S. naval operations meant that all but the newest ships decommissioned in 1946 and 1947. Those that did stay on in service as seaplane tenders decommissioned between the mid-1950s and 1960s, some seeing service in the Korean War (1950–1953). The last unit did not leave U.S. Navy service until 1973.

However, the ships proved versatile and durable, and had long second lives postwar. Between c. 1949 and 1965 three served, on a rotating basis, as flagships for the Commander, Middle Eastern Forces, before one, Valcour, took on the job permanently, under the revised designation of AGF-1, serving until 1971. Some became oceanographic and hydrographic survey ships, either in U.S. Navy, United States Coast and Geodetic Survey, or Greek service. Eighteen were transferred to the United States Coast Guard – where they became known as Casco-class cutters – between 1946 and 1949 for service mostly as weather reporting ships, a role they played until the late 1960s and early 1970s; some of the Coast Guard ships saw service in the Vietnam War, and one survived as a cutter until 1988. A number of the units of the class were transferred to foreign navies, including those of Ethiopia, Italy, Norway, the Philippines, and South Vietnam, for use as patrol vessels and training ships, and a few saw commercial service as cruise ships in Greece. The murky information available on a unit incorporated into the Vietnam People's Navy after the fall of South Vietnam in 1975 suggests that she remained active until at least 2000 and may remain active today; even if reports of her longevity are inaccurate, the last member of this large and long-lived class of ships did not leave service until 1993, when the ship transferred to Italy was decommissioned by the Italian Navy.

Ships

USS Barnegat (AVP-10) , lead unit of the class, was commissioned in July 1941. She served in the Atlantic until February 1945, then finished World War II in the Pacific. She was in reserve from 1945 to 1958, then was sold into commercial service and was the Greek cruise ship MV Kentavros from 1962 to 1986.

USS Biscayne (AVP-11, later AGC-18) was in commission from 1941 to 1946. During the first half of World War II, she saw service as a seaplane tender in the Atlantic, in the Caribbean, in West Africa, and in North Africa. Converted into an amphibious force flagship in 1943, she served in the Mediterranean in 1943–1944, seeing action in the amphibious landings in Operation Avalanche at Salerno, Operation Shingle at Anzio, and Operation Dragoon in southern France. Redesignated AGC-18 in 1944, she then served in the Pacific in 1945, serving at Iwo Jima, in the Okinawa campaign, and in the Philippines before the war ended. Postwar, she served in Korea and China. She was transferred to the U.S. Coast Guard postwar as , later WAVP-385, later WHEC-385, and was in commissioned Coast Guard service from 1949 to 1952 and from 1958 to 1968.

USS Casco (AVP-12) was in commission from 1941 to 1947, performing her World War II service in the Pacific. She was transferred to the U.S. Coast Guard postwar as , later WHEC-370, and was in commissioned Coast Guard service from 1949 to 1969.

USS Mackinac (AVP-13) was in commission from 1942 to 1946, performing her World War II service in the Pacific. She was transferred to the U.S. Coast Guard postwar as , later WHEC-371, and was in commissioned Coast Guard service from 1949 to 1968.

USS Humboldt (AVP-21) was in commission from 1941 to 1947, performing her World War II service in the Atlantic and Mediterranean, where during the Natal Conference, she flew the Commander-in-Chief's flag. She was among three Barnegat-class ships selected in 1945 for conversion to a press information ship, redesignated AG-121, for the projected invasion of Japan in 1945–1946, but the war ended before the invasion could take place and she was converted back into a seaplane tender. She was transferred to the U.S. Coast Guard postwar as , later WHEC-372, and was in commissioned Coast Guard service from 1949 to 1969.

USS Matagorda (AVP-22) was in commission from 1941 to 1946, performing her World War II service in the Atlantic. She was among three Barnegat-class ships selected in 1945 for conversion to a press information ship, redesignated AG-122, for the projected invasion of Japan in 1945–1946, but the war ended before the invasion could take place and she was converted back into a seaplane tender. She was transferred to the U.S. Coast Guard postwar as , later WHEC-373, and was in commissioned Coast Guard service from 1949 to 1968.

USS Absecon (AVP-23) was in commission from 1943 to 1947. She was converted while under construction into a catapult training ship, and spent World War II in Florida waters training battleship and cruiser floatplane pilots in catapult launches, also serving as a mobile target for torpedo planes. She was transferred to the U.S. Coast Guard postwar as , later WHEC-374, and was in commissioned Coast Guard service from 1949 to 1972. She was transferred to South Vietnam in 1972 and served in the Republic of Vietnam Navy as the frigate until captured by North Vietnam on the collapse of the South Vietnamese government at the end of the Vietnam War in 1975. She then served the Socialist Republic of Vietnam in the Vietnam People's Navy as the patrol vessel and participated in naval operations against the Khmer Rouge during the Cambodian-Vietnamese War. She continued her service with the Vietnamese Navy until perhaps as late as 2000.

USS Chincoteague (AVP-24) was in commission from 1943 to 1946, performing her World War II service in the Pacific. She was transferred to the U.S. Coast Guard postwar as , later WHEC-375, and was in commissioned Coast Guard service from 1949 to 1972. She was transferred to South Vietnam in 1972 and served in the Republic of Vietnam Navy as the frigate . Upon the collapse of the South Vietnamese government at the end of the Vietnam War in 1975, she fled to the Philippines. She served in the Philippine Navy from 1975 to 1985 as the frigate RPS (later BRP) Andrés Bonifacio (PF-7).

USS Coos Bay (AVP-25) was in commission from 1943 to 1946, performing her World War II service in the Pacific. She was transferred to the U.S. Coast Guard postwar as , later WHEC-376, and was in commissioned Coast Guard service from 1949 to 1966.

USS Half Moon (AVP-26, ex-AGP-6, ex-AVP-26) was laid down as a seaplane tender, then was chosen as one of four Barnegat-class ships to be converted to a motor torpedo boat tender prior to completion and redesignated AGP-6, but ultimately was completed as a seaplane tender, with her sister ship becoming the motor torpedo tender AGP-6 instead. She was in commission from 1943 to 1946, performing her World War II service in the Pacific, where she saw action in the New Guinea campaign and the Philippines campaign. She was transferred to the U.S. Coast Guard postwar as , later WHEC-378, and was in commissioned Coast Guard service from 1948 to 1969.

USS Mobjack (AGP-7, ex-AVP-27)