World War Il’s Admirable-class minesweepers were built on the same 184- foot, 6-inch hull as the PCE-821-class convoy escorts but were equipped to counter moored and acoustic mines at the expense of some antiaircraft and antisubmarine capabilities. The hull numbers of the 174 ordered included AM-136-165, 214-311, 351-366, and 391-420, but only 125 were completed for the Navy, one as degaussing tender YDG-11. Russia received 34 of the total (12 after hostilities had ended) and Nationalist China received 19 (14 of them post-war), while the Philippines obtained two in 1948 and Burma one in 1967. Mexico acquired 21, most of them in 1962; of those, a dozen still are in service as patrol ships. At 945 tons full load, the Admirables could achieve 14.8 knots on their two 855 brake horsepower diesels.
The photo of the Admirable (AM-136) at completion in April 1943 (top right) shows the after 3-inch gun that was mounted in a few early units; it was replaced by two single 40-mm Army Mk 3 antiaircraft guns in side-by-side tubs in units delivered into 1944. By 1945, the ships remaining in U.S. Navy service had twin 40-mm mounts. The Admirable became T.521 in the Russian Pacific Fleet in late 1945.
The Pinnacle (AM-274) is shown in June 1945, with 3-inch gun, hedgehog antisubmarine mortar, and two 20-mm guns on the foredeck; two more 20-mm mounts on the wings of the pilothouse deck; two twin 40-mm mounts at the forecastle break; and the other two 20-mm mounts on the fantail, which also accommodated the sweep gear, two depth-charge racks, and two depth- charge mortars. Both surface-search and air-search radars are fitted. The Pinnacle saw service in the Mediterranean and Black Sea in 1944-45 before being transferred to the Pacific, where she participated in the cleanup of Japanese mine fields until transferred to Nationalist China in July 1948.
The Crag (AM-214)—pictured here— and the Cruise (AM-215), although both launched on 21 March 1943, were not completed until August and September 1945, respectively, as German-style magnetic mine-countermeasures ships with external solenoid coils covered by extensive ductwork. Despite later removal of their moored sweep gear and a reduction of their armament to one twin 40-mm gunmount aft and four single 20-mm mounts, they displaced 140 tons more than their sisters and could achieve only nine knots. The Cruise never was used in her intended role, but the Crag cleared Japanese mines in the Hainan Straits and Hong Kong harbor during 1946.