Laid down, 16 August 1951 at Fulton Shipyard, Antioch, CA; Launched, 14 February 1953; Commissioned USS Constant (AM-427), 8 September 1954; The fifth of the Aggressive class.  Reclassified as an Ocean Minesweeper MSO-427, 7 February 1955; Decommissioned, 30 September 1992; Struck from the Naval Register, 9 March 1994; Sold for scrapping to Crowley Marine, removal date 29 September 1999; Scrapped, 1 April 2001.

Displacement 630 t.(lt), 755 t.(fl); Length 172'; Beam 35'; Draft 10'; Speed 14 kts; Complement 6 Officers, 74 Enlisted; Armament, as built, one single 40mm gun mount, two .50 cal machine guns, final configuration, bow gun replaced by one twin 20mm gun mount, two .50 cal. machine guns remain; Propulsion, four Packard ID1700 diesel engines, two shafts, two controllable pitch propellers.