 In July 1917 S1 reverted to her original name and was converted to a surface patrol vessel between 27 June 1917 and 24 January 1918 . Her torpedo tubes and disappearing guns were removed . She was given a forecastle , a bridge and her funnel was fixed in place and extended . She was rearmed with a pair of 12 @-@ pounder ( 3 inch , 76 mm ) guns and depth charges , weapons more suitable for her new role as an anti @-@ submarine patrol boat . Swordfish joined the 1st Destroyer Flotilla at Portsmouth upon completion of her sea trials , but nothing is known of her subsequent service . 
