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Submarine Chaser Photo Archive

USS SC-431

Call sign:
Nan - Charlie - Easy - Roger

ex-USS PC-431

Call sign (1924):
Nan - Oboe - Pup - Rush

ex-USCGC Knudsen (CGSC 431)

Call sign (1920):
George - Vice - Jig - Sail

ex-USS PC-431

Call sign (1919):
George - Have - Quack - King

SC-431 served both the U. S. Navy and Coast Guard

SC-1 Class Submarine Chaser:

  • Built as PC-431 by the Matthews Boat Co., Port Clinton, OH
  • Served in the 9th, 10th and 11th Naval Districts
  • Transferred to the Coast Guard 29 October 1919 and named USCGC Knudsen (CGSC 431)
  • Named for Machinist Wilhelm Knudsen, USCG, a member of the torpedoed USCGC Tampa, lost during World War I
  • Returned to the U.S. Navy 31 August 1921
  • Commissioned USS PC-431, 1 September 1921
  • Served as a Naval Reserve training vessel in 1939 in the 3rd Naval District at New York City
  • Reclassified SC-431 in April 1943
  • Transferred to the Maritime Commission for disposal 9 December 1946
  • Acquired in 1948 by William A. Mercer of White Stone, VA for use as a fishing boat and named Admiral
  • Acquired in 1954 by Elwood F. Dryden of Odd, VA
  • Acquired in 1967 by Robert Coleman Tillage of Gloucester Point, VA
  • Acquired in 1978 by Gloucester Trawlers, Inc. of Hayes, VA and renamed Sea Mist
  • Out of documentation in 1984
  • Fate unknown.


  • Displacement 77 t.
  • Length 110'
  • Beam 13' 6"
  • Draft 6' 3"
  • Speed 18 kts.
  • Complement 17
  • Armament: One 3"/23 gun mount, two .30 cal. machine guns, and one depth charge projector "Y Gun"
  • Propulsion: Three 220shp Standard gasoline engines, three shafts
    World War II - Three Hall-Scott gasoline engines.

    Click on thumbnail
    for full size image
    Size Image Description Source
    SC-433 73k SC-431 and SC-433 Historical Collections of the Great Lakes
    SC-431 206k 22 December 1941
    Norfolk Navy Yard, Portsmouth, VA
    Dan Treadwell
    SC-431 199k
    SC-431 186k 22 December 1941
    Norfolk Navy Yard, Portsmouth, VA
    The Covered Lighter YF-56 is in the background
    SC-431 114k 22 December 1941
    Norfolk Navy Yard, Portsmouth, VA.
    SC-431 86k
    SC-431 150k
    SC-431 170k

    There is no DANFS history available for SC-431

    Excerpts from the original log of the Old Chicago Coast Guard Station regarding SC-431, 433, 437 and SC-438

    October 13th , 1919

    At 10:30 A.M. received telephone message from Capt. Conner USCG request that five enlisted men be subsisted at this station while getting the Sub Chaser No. 438 in readiness to sail for
    Duluth, Minn.

    October 16th, 1919

    Sub Chaser No. 438 was towed to station at 3:00 P.M. and moored, crew insisting in getting same in readiness, fitting out and overhauling equipment.

    October 24th, 1919

    District Superintendent and Keeper commenced taking inventory of equipment on Sub Chaser which are to be turned over to Coast Guard.

    October 25th ,1919

    Superintendent and keeper taking inventory of equipment on Sub Chaser No. 437-431, and 433.

    October 26th, 1919

    Surfman Elmer C. Anderson from Coast Guard Station #289, arrived at this station at 10:00 A.M. having been temporarily transferred to this station as SHIPKEEPER on Sub Chaserís laid up at Chicago, H.L.-10/20/19 (73-531).

    October 28th, 1919

    District Superintendent, Keeper, and surfman Anderson, taking inventory on Sub Chasers No. 431, 433, and 437, making preparation for laying up the ships for winter.

    January 29th, 1920

    Surfman Anderson who is ship keeper on Sub Chasers , Chicago River was directed to hospital which will probably require a few days.

    December 27th, 1920

    Boatswain (L) left station and proceeded to Sub Chaser at North Ave. Bridge, looked over all the engines and found that the Auxiliary engine which is used for generating light system, and charging storage batteries, had not been drained on the night of the 25th, by Surfman Shipley, and caused the cylinder heads and compressor to freeze and crack. Report of the above has been forwarded to District Superintendent. Returned to station at 4:00 p.m.

    January 20, 1921

    District Superintendent 12 District, Green Bay Wisc., arrived at the station 10:45 A.M., mustered crew and looked at all property on the station. Departed station at 1:30 P.M. accompanied by Boatswain (L) J.O Anderson, to Sub Chasers 431, 433, 437, and launch open boat search arriving on board at 2:30 P.M. Made a thorough examination of the heater and engine which has been cracked on December 25, 1920 by neglect by Surfman Shipley and S. Martin whom were left as charge as caretakers. District Superintendent left Sub Chasers at 4:00 P.M.

    March 30th, 1921

    Note: Coast Guard General Court Closed after 4 days of hearing of accused Surfman Martin and Surfman Shipley. Officer Molloy, Super B. G. Mothberg and R. C. Hiemer (JG) were conveyed on shore by surfboat.

    June 26th, 1921

    At 8:00 a.m. Boatswain (L), and two Surfman left the station for North Ave. Bridge and River. removed Sub Chaser No.431-433-437, from North Branch, Chicago River to North end of Lincoln Park Lagoon and moored safe. Permission for mooring Sub Chaser was granted to the Coast Guard by Park Commissioners, Lincoln Park. Reasons for mooring Sub Chasers is that the North Branch Chicago River being very dirty and unfit for the men to live on board.

    August 26th, 1921

    Letter received from District Superintendent pertaining to the Sub Chasers No. 431-433-437 to be transferred from the Coast Guard to the Navy Department. Arrangements for return of these vessels are being made with Commandant, 9th Naval Dist.

    August 31st, 1921

    Boatswain(L) J.O Anderson left station at 1000 am proceeded to Lincoln Park and completed the inventory of public property on board the three Sub Chaser 431-433-437. Transferred to the Navy Department August 31, 1921.

    Contributed by Herbert J. Harmon, CWO3
    Commanding Officer
    U. S. Coast Guard Station
    Calumet Harbor
    4001 E. 98th St Chicago ILL, 60617

    Additional Resources and Websites of Interest
    Patrol Craft Sailors Association
    Back To The Main Photo Index Back To the Patrol Craft/Gunboat/Submarine Chaser Ship Type Index Back to the 110' Submarine Chaser (SC) Photo Index

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