USS Constant, (AM-427/MSO-427) was an Aggressive class minesweeper vessel in the United States Navy.Constant was laid down on 16 August 1951 at Fulton Shipyard, Antioch, California and launched on 14 February 1953. She was commissioned as Constant, AM-427) on 8 September 1954 and later reclassified as an Ocean Minesweeper MSO-427 on 7 February 1955.