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NavSource Online: Mine Warfare Vessel Photo Archive

Courtesy of Al Grazevich

Contributed by Mike Smolinski

Assurance (AG 521)

Call sign:
November - Romeo - Alpha - Echo

Ability Class Minesweeper:

  • Laid down 28 January 1957 by Peterson Builders, Inc., Sturgeon Bay, WI
  • Launched, 31 August 1957
  • Commissioned USS Assurance (MSO-521), 21 November 1958 at Boston Naval Shipyard, Charlestown, MA
  • Reclassified as a Miscellaneous Auxiliary, AG-521, 1 March 1973
  • Decommissioned, 30 September 1977 and struck from the Navy Register
  • Sold for scrap 1 July 1978 by the Defense Reutilization and Marketing Service to Ampel Wrecking and Dismantling Corp.


  • Displacement 934 t.
  • Length 190'
  • Beam 36'
  • Draft 12'
  • Speed 15 kts.
  • Complement 83
  • Armament: Two .50 cal. machine guns
  • Propulsion: Two 1,400hp General Motors 8V498 diesel engines, two shafts, two controllable pitch propellers.
    Click on thumbnail
    for full size image
    Size Image Description Source
    USS Assurance (MSO 521)
    Assurance 61k Photo courtesy Peterson Builders USS Assurance website
    Dick Lewis
    Assurance 179k Peterson Builders photo from the Door County Maritime Museum, Sturgeon Bay, WI Michael Cosgrove
    Assurance 103k c. 1965
    Valletta, Malta
    Photo courtesy A. & J. Pavia from the 1966/1967 edition of Jane's Fighting Ships
    Original photo: Robert Hurst
    Replacement photo: Richard Miller, BMCS, USNR, Ret.
    Assurance 208k c. 1969
    Valletta, Malta
    Photo courtesy A. & J. Pavia
    Robert Hurst
    USS Assurance (AG 521)
    Assurance 112k U.S. Navy photo Tom Langford
    Assurance 305k National Archives photo UA 50.01.01 Mike Green
    Assurance 60k c. 1973
    Seen here as AG-521 a Sonar Research Ship
    USS Assurance website
    Dick Lewis
    Assurance 343k c. 1973
    Nassau, Bahamas
    Astern of the RMS Queen Elizabeth 2
    Michael Cosgrove

    Commanding Officers
    01LCDR Frank Lyons Crump, Jr., USN - USNA Class of 1948-A21 November 1958 - 29 July 1960
    02LCDR Thomas James Porcari, USN29 July 1960 - June 1962
    03CDR James Egerton Myrick, USN - USNA Class of 1948-BJune 1962 - June 1964
    04LCDR John Elroy Bethany, USNJune 1964 - 24 March 1966
    05LT/LCDR Norbert Patrick Murphy, USN24 March 1966 - 25 July 1968
    06LT/LCDR Sanford Joe Snuffer, USN25 July 1968 - 27 August 1970
    07LCDR George Roberts Oldham, USN27 August 1970 - 30 October 1970
    08LT James Clark Jacobs, USN30 October 1970 - February 1971
    09LCDR George Roberts Oldham, USNFebruary 1971 - August 1972
    10LCDR Robert Lewis Beauchamp, USN - USNA Class of 1965August 1972 - July 1974
    11LCDR William Barclay Tirrell, Sr., USN - USNA Class of 1968July 1974 - October 1976
    12LT Richard Scott Hillyer, USN - USNA Class of 1969October 1976 - 30 September 1977
    Courtesy Wolfgang Hechler, Ron Reeves and Bill Gonyo

    View the Assurance (MSO-521)
    DANFS History entry located on the Haze Gray & Underway Website
    Additional Resources and Websites of Interest
    102 Minesweepers (MSO) Oceangoing Minesweepers
    Back to the Main Photo Index Back to the Mine Warfare Ship Photo Index Back to the Ocean Minesweeper (MSO) Photo Index Back to the Auxiliary Ship Index Back to the Miscellaneous Auxiliary (AG) Photo Index

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    This page was created by Gary P. Priolo & maintained by Joseph M. Radigan (of blessed memory) & Michael Mohl
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