Wilton class (1 ship, launched 18 January 1972) open-water minesweeper and minehunter. Prototype ship built in Glass Reinforced Plastic (GRP) to same hull design as Ton class and forerunner of Hunt and Sandown classes also constructed in GRP.
United States Navy minesweepers in World War II can be put into 4 groups. First there were the 49 WW1-era Lapwings. Most of them were reclassified to serve as tugs, seaplane tenders and rescue ships.
The second group comprised the steel hull 2 Raven, 71 Auks and 123 Admirables that were conceptually similar to submarine chasers (PC-461-class and PCE-842-class). They were ocean-going, but their primary area of operation was coastal waters. They carried substantial anti-submarine warfare equipment: depth charges, depth charge throwers and hedgehogs and with this they could fulfill merchant escort duties. The 18 Adroits were PCE-842 boats built as minesweepers, but considered unsatisfactory for their purpose and converted to regular patrol craft. Several Auks were given to the Royal Navy, numerous Admirables to the Soviet Union. The Ravens were the first new minesweepers after a gap of almost 2 decades and they were the first to use diesel propulsion. The Auks used diesel-electric propulsion, because the availability of electrical energy removed the need for additional service generators. At over 3000shp they were also quite powerful and thus relatively fast. The Admirables again used geared diesels, they were considerably shorter than the Auks and only had half the power,but they came with lower cost. The Auk and Admirable classes were produced in parallel and their hull numbers overlap.
The third group was formed by the 481 wooden hull YMS-1-classminesweepers, similar in size and construction to the wooden hull SC-497-classsubmarine chasers. Wooden hulls were especially useful for minesweepers for it virtually eliminated the magnetic signature of the boat. These boats were smaller than their steel hull counterparts, were (probably) not going to cross the ocean under their own power and seakeeping fortunes and had no hedgehogs and only 2 depth charge throwers.
The fourth group consisted of 24 Gleaves-classdestroyers that were converted relatively late in the war, but which were much faster and also better armed than any of the other minesweepers, even after the reduction in armament that came with the conversion.
The 3 Hawk were converted fishing boats and they are pretty much irrelevant because of the small quantity and lack of impact on design.
