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NavSource Online: Mine Warfare Vessel Photo Archive

HM BYMS-2171
ex-HM J-971

BYMS-2171 served the Navies of Great Britian and Greece

YMS-1 Class Auxiliary Motor Minesweeper:

  • Laid down 22 May 1942 as YMS-171 by Henry C. Grebe and Co., Chicago, IL
  • Launched 21 November 1942
  • Completed 29 March 1943
  • Transferred to Great Britian 8 April 1943 and reclassified HM J-971
  • Reclassified HM BYMS-2171
  • Returned to U.S. custody 27 April 1946, transferred to Greece and named Keffallina (M 207)
  • Struck from the Naval Register 8 September 1952
  • Struck from the Greek Navy list in 1966
  • Fate unknown.


  • Displacement 270 t.
  • Length 136'
  • Beam 24' 6"
  • Draft 8'
  • Speed 13 kts.
  • Complement 50
  • Armament: One 3"/50 dual purpose gun mount and two 20mm mounts
  • Propulsion: Two 880bhp General Motors 8-268A diesel engines, Snow and Knobstedt single reduction gear, two shafts.
    Click on thumbnail
    for full size image
    Size Image Description Source
    YMS-171 132k 18 March 1943
    Imperial War Museum photo IWM (FL 7342)
    Mike Green
    HM J-971
    YMS-171 199k . Paul Silverstone

    There is no DANFS History currently available for YMS-171
    Additional Resources and Web Sites of Interest
    Naval Minewarfare Association
    Association of Minemen
    Back To The Main Photo Index Back To the Mine Warfare Ship Photo Index Back to the Auxiliary Motor Minesweeper (YMS) Photo Index

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    This page created and maintained by Joseph M. Radigan
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