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NavSource Online: Mine Warfare Vessel Photo Archive

Left patch courtesy of Paul Haaze - right courtesy of Mike Smolinski

Impervious (MSO 449)
ex-AM-449

Call sign:
November - Mike - Lima - Victor

Aggressive Class Minesweeper: Laid down 18 November 1951 at Martinolich Shipbuilding Co., San Diego, CA; Launched, 29 August 1952; Commissioned USS Impervious (AM-449), 15 July 1954; Reclasified as an Ocean Minesweeper, MSO-449, 7 February 1955. Impervious changed divisions in September 1967 and became a part of Mine Division 71. The division consisted of: Dynamic (MSO 432), Engage (MSO 433), Impervious, Inflict (MSO 456) and Fortify (MSO 446). Decommissioned, 12 December 1991; Struck from the Navy Register 18 March 1992; Sold for scrap 18 August 1994 to NRA Acquisition, Inc. of New York, NY, sub-contracted to Wilmington Resources Inc. of Wilmington, NC for disposal, Repossessed by Navy after contractor defaulted due to sub-contractor being closed by state of North Carolina for environmental pollution; Sold for scrap 4 December 2000 to Baltimore Marine Industries of Baltimore, MD.

Specifications: Displacement 775 t; Length 172'; Beam 35'; Draft 12'; Speed 14 kts; Complement eight officers, 70 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, replaced by four Waukasha Motors Co. diesels, two shafts, two controllable pitch propellers.

Size	Image Description	Source
141k	Ready for christening, during launching ceremonies at the Martinolich Shipbuilding Company shipyard, San Diego, California, on 29 August 1952. Official U.S. Navy Photograph, now in the collections of the National Archives. National Archives photo 80-G-447598.	Naval Historical Center
109k	Impervious is christened by Miss Mary Lin Moore, during launching ceremonies at the Martinolich Shipbuilding Company shipyard, San Diego, California, 29 August 1952. National Archives photo 80-G-447599 at the Naval Historical Center.	Bill Gonyo
180k	-	USS Impervious (MSO-449) Web Site Rick Szpyrka
98k	U.S. Navy photo.	Wendell Royce McLaughlin, Jr.
246k	Fortify, Engage, and Impervious steaming with an unidentified minesweeper	Tom Lawson
100k	Departing Long Beach, CA for Japan. U.S. Navy photo from the December 1955 edition of All Hands magazine	Joe Radigan
74k	c. 1966/1967 Tonkin Gulf, South China Sea Coming alongside Ponchatoula (AO 148) to refuel	Barry Litchfield
45k	c. 1971 Pearl Harbor, HI Photo enhanced by Tom Kermen	USS Impervious (MSO-449) Web Site Robert Sterling, Jr.
32k	c. 1971 Pearl Harbor, HI Photo enhanced by Tom Kermen	USS Impervious (MSO-449) Web Site Robert Sterling, Jr.
44k	-	USS Impervious (MSO-449) Web Site Robert Sterling, Jr.
64k	14 November 1991 Impervious, foreground, and Adroit (MSO 509) sit aboard the Dutch heavy lift ship Super Servant 4 as its deck is submerged to permit minesweepers to be unloaded. The Impervious, the Adroit and a third ocean minesweeper, the Leader (MSO 490), have returned to Norfolk, VA after being deployed for 14 months in the Persian Gulf region in support of Operation Desert Shield and Operation Desert Storm. .	Defense Visual Information Center PHAN Christopher L. Ryan
97k	14 November 1991 Impervious, foreground, and Adroit (MSO 509) sit aboard the Dutch heavy lift ship Super Servant 4 as its deck is submerged to permit minesweepers to be unloaded. .	Defense Visual Information Center PHAN Christopher L. Ryan
107k	14 November 1991 Impervious, is moved to the pier after being unloaded from the Dutch heavy lift ship Super Servant 4.	Defense Visual Information Center PHAN Christopher L. Ryan
96k	14 November 1991 Impervious, is moved to the pier by the large harbor tug Santaquin (YTB 824), and a civilian tug after being unloaded from the Dutch heavy lift ship Super Servant 4. .	Defense Visual Information Center PHAN Christopher L. Ryan
39k	14 November 1991 A work boat comes alongside Impervious, as it sits on the deck of the Dutch heavy lift ship Super Servant 4. .	Defense Visual Information Center PH3 Paul A. Hawthorne
65k	c. December 2000 Awaiting scrapping at Baltimore, MD.	Save An MSO Web Site Dick Lewis