USS Adroit (AM-509/MSO-509) was an Acme-class minesweeper acquired by the U.S. Navy for the task of removing mines that had been placed in the water to prevent the safe passage of ships. The second ship to be named Adroit by the Navy, MSO-509 was laid down on 18 November 1954 at Boothbay Harbor, Maine, by Frank L. Sample, Jr., Inc. as AM-509; redesignated MSO 509 on 7 February 1955, named Adroit on 17 May 1955; launched on 20 August 1955; sponsored by Mrs. Alice G. Olsen, the wife of Capt. Eliot Olsen, and commissioned on 4 March 1957, Lt. Comdr. J. G. Nemetz in command.