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NavSource Online: Mine Warfare Vessel Photo Archive


Courtesy of Al Grazevich


Patchs courtesy of Paul Haaze, Mike Smolinski and Wolfgang Hechler

Impervious (MSO 449)
ex-AM-449


Call sign:
November - Mike - Lima - Victor

Aggressive Class Minesweeper:

  • Laid down 18 November 1951 by Martinolich Shipbuilding Co., San Diego, CA
  • Launched 29 August 1952
  • Sponsored by Miss Mary-Lin Moore
  • 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 and laid up at Naval Inactive Ship Maintenance Facitity, Portsmouth, VA
  • 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 U.S. 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 78
  • Armament: As built, one single 40mm gun mount and 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.
    Click on thumbnail
    for full size image
    Size Image Description Source
    Impervious (AM 449)
    Impervious 201k 29 August 1952
    Launching Ceremonies Program
    Darryl Baker
    Impervious 532k
    Impervious 246k
    Impervious 69k
    Impervious 141k Ready for christening, during launching ceremonies at the Martinolich Shipbuilding Company shipyard, San Diego, California, on 29 August 1952
    National Archives photo 80-G-447598.
    Naval Historical Center
    Impervious 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
    Bill Gonyo
    Impervious 589k 8 June 1954
    National Archives photo from the Bureau of Ships collection National Archives Identifier 6933109
    Robert Hurst
    USS Impervious (MSO 449)
    Impervious 180k . USS Impervious (MSO-449)
    Website
    Rick Szpyrka
    Impervious 98k U.S. Navy photo Wendell Royce McLaughlin, Jr.
    Fortify, Engage & Impervious 246k Fortify (MSO 446), Engage (MSO 433), and Impervious steaming with an unidentified minesweeper Tom Lawson
    Engage/Fortify/Impervious 538k Portland, Oregon
    Engage (MSO 433), Fortify (MSO 446) and Impervious at the Rose Festival Fleet Week
    Tommy Trampp
    Impervious 100k Departing Long Beach, CA for Japan.
    U.S. Navy photo from the December 1955 edition of All Hands magazine
    Joe Radigan
    Impervious 74k c. 1966
    Tonkin Gulf, South China Sea
    Coming alongside Ponchatoula (AO 148) to refuel
    Barry Litchfield
    Engage 316k 13 December 1966
    Mine Division 71 Welcome Home pamphlet
    Tom Nutt
    Engage 173k
    Engage 169k
    Engage 181k
    Impervious 45k c. 1971
    Pearl Harbor, HI
    Photo enhanced by Tom Kermen
    USS Impervious (MSO-449)
    Website
    Robert Sterling, Jr.
    Impervious 32k
    Impervious 44k -
    Impervious 394k 7 July 1990
    Passing Fort Leslie J. McNair after departing the Washington Navy Yard
    U.S. Navy photo DN-ST-90_11011
    Original photo: Bill Gonyo
    Replacement photo: Robert Hurst
    Impervious 418k 5 October 1990
    Bahrain
    Impervious
    and other vessels are positioned on the partially submerged deck of the Dutch heavy lift ship Super Servant 3 prior to offloading in support of Operation Desert Shield
    U.S. Navy photo DN-SSC--91-02579 by CDR John Charles Roach
    Robert Hurst
    Impervious 177k c. October 1990 Richard Miller, BMCS, USNR, Ret.
    Impervious 271k c. 1991
    Desert Storm Pro Set card
    Tommy Trampp
    Impervious 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 Operations Desert Shield and Desert Storm.
    Photo by PHAN Christopher L. Ryan
    Defense Visual Information Center
    Impervious 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
    Photo by PHAN Christopher L. Ryan
    Impervious 107k 14 November 1991
    Impervious, is moved to the pier after being unloaded from the Dutch heavy lift ship Super Servant 4
    Photo by PHAN Christopher L. Ryan
    Impervious 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
    Photo by PHAN Christopher L. Ryan
    Impervious 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
    Photo by PH3 Paul A. Hawthorne
    Impervious
    Impervious 65k c. December 2000
    Awaiting scrapping at Baltimore, MD.
    Save An MSO Website
    Dick Lewis

    Commanding Officers
    01LT Albert Tenney Ford, USN15 July 1954 - October 1955
    02LCDR Maurice Cleveland Orbeton, Jr., USNOctober 1955 - July 1957
    03LCDR Charles E. Delaney, USNJuly 1957 - 1959
    04LCDR Leo Grant Hinchcliff, Jr., USN1959 - July 1960
    05LCDR Richard Anthony Dalla Mura, USNJuly 1960 - March 1962
    06LT Gerald Eustis Thomas, USN - Retired as Rear AdmiralMarch 1962 - 20 June 1963
    07LCDR Russell Benjamin Bridgham, USN20 June 1963 - August 1965
    08LT Eugene Arthur Spadoni, USNAugust 1965 - February 1967
    09LT Randy F. Witt, USNFebruary 1967 - July 1969
    10LT Dennis Marchant McCord, USNJuly 1969 - October 1970
    11LT D. A. Oriss, USNOctober 1970 - March 1972
    12LCDR Felix Michael (Mike) Reynolds, USNMarch 1972 - August 1973
    13LCDR Ernest Harriman Joy, Jr., USNAugust 1973 - October 1975
    14LT James Albert Hooper, IV, USNOctober 1975 - August 1977
    15LCDR James Francis Howick, USNAugust 1977 - 3 November 1979
    16LCDR Donald Hendrix Nash, USN3 November 1979 - 16 January 1982
    17LCDR Robert Edward Lee, USN16 January 1979 - 11 February 1984
    18CDR Earl Robert Jones, USN11 February 1984 - 24 April 1986
    19LCDR Jerome E. Grause, Jr., USN24 April 1986 - August 1988
    20LCDR William K. Midgette, USNAugust 1988 - September 1988
    21LCDR John G. Hegeman, USNSeptember 1988 - 10 January 1989
    22LCDR Stephen Craig Bradley, USN10 January 1989 - 13 October 1990
    23LCDR David Moore Jackson, USN13 October 1990 - April 1991
    24LCDR Vernon A. Edelman, USNApril 1991 - November 1991
    25LCDR David Moore Jackson, USNNovember 1991 - 12 December 1991
    Courtesy Wolfgang Hechler and Ron Reeves

    View Impervious (MSO-449) Crew Photos
    View the Impervious (MSO-449)
    DANFS History entry located on the Haze Gray & Underway Website
    Additional Resources and Web Sites of Interest
    102 Minesweepers (MSO) Oceangoing Minesweepers
    Naval Minewarfare Association
    Association of Minemen
    Back To The Main Photo Index Back To the Mine Warfare Ship Photo Index Back to the Ocean Minesweeper (MSO) Photo Index

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