USS R - 21 ( SS - 98 ) USS " R - 21 " ( SS - 98 ) was an " R " - class coastal and harbor defense submarine of the United States Navy . Her keel was laid down on 19 April 1917 by the Lake Torpedo Boat Company in Bridgeport , Connecticut ; the R - boats built by Lake Torpedo Boat ( R - 21 through R - 27 ) are sometimes considered a separate class from those built by Fore River Shipbuilding ( R - 1 through R - 14 ) and Union Iron Works ( R - 15 through R - 20 ) . She was launched on 10 July 1918 sponsored by Mrs . Dallas C . Laizure and commissioned on 17 June 1919 with Lieutenant Commander Morris D . Gilmore in command . Service history . Attached to Submarine Division 1 , " R - 21 " operated out of the submarine base at New London , Connecticut . She conducted diving and approach tactical training in Long Island Sound , and conducted several training cruises in the vicinity of Block Island with other units of the division . Following a recruiting cruise to New Haven , Connecticut , and Bridgeport , Rhode Island , from 20 August to 27 August , she returned to New London for upkeep . " R - 21 " continued practice dives off the coast into the fall with a call at the Torpedo Station , Newport , Rhode Island , on 21 October . She departed New London on 1 November 1919 in company with , , , and " Eagle No . 31 " . Proceeding via Hampton Roads , Wilmington , North Carolina , Savannah , Georgia , Key West , Florida , Havana , Cienfuegos , and Guantanamo Bay , Cuba ; and Kingston , Jamaica , she arrived at Coco Solo , Panama Canal Zone , on 11 December . Following several practice dives out of Coco Solo , she transited the Panama Canal on 27 January 1920 for drydock work at Balboa . Returning to Coco Solo , " R - 21 " continued to refine her diving , approach , and torpedo tactics through the spring and summer . During two trips to Almirante Bay , 30 March - 2 April and 17 – 20 May , she practiced with other units of the first division . Given hull classification symbol SS - 98 in July , " R - 21 " again transited the canal to Balboa 27 September for a month in drydock . Upon returning to Coco Solo , she was laid up for 11 months of extensive overhaul . She sailed north on 26 September 1921 via Guantanamo Bay , Key West , and New York City , arriving New London on 27 October . She sailed to Portsmouth , New Hampshire , on 27 December for refitting . A successful test dive on 26 May 1922 meant that " R - 21 " could return to New London . Through the spring and summer months she operated out of New London and Newport . The craft of Submarine Division 1 sailed from New London on 2 October 1922 for Coco Solo . " R - 21 " served as flagship as the boats cruised via Hampton Roads and Guantanamo . After 11 days out , " R - 24 " developed engine trouble and was temporarily taken under tow by " R - 21 " . The Cuba - bound steamer SS " Bethore " rendered assistance , and " R - 21 " arrived at Coco Solo on 27 October . " R - 21 " spent the rest of her active Navy days operating out of Coco Solo and undergoing repairs at Balboa . She sailed from Coco Solo for the last time 15 February 1923 in company with a tender , , and eight other submarines . Two days later " R - 21 " s engines malfunctioned and she was towed into Guantanamo by the tender . Repairs were quickly accomplished and " R - 21 " sailed for Philadelphia , Pennsylvania , on 22 February , arriving there via Charleston , South Carolina , on 9 November 1923 . Decommissioned at the Philadelphia Navy Yard on 21 June 1924 , " R - 21 " was struck from the Naval Vessel Register on 9 May 1930 and sold for scrap 30 July 1930 .