The S-3 Class SS-117 coastal and harbor defense submarine was 231′ in length, beam of 21’10″; surface displacement of 876 tons, submerged displacement of 1,092 tons and draft of 13’1″. The vessel held 4 officers and 34 enlisted men. The boat could operate to depths of 200 feet and was armed with five 21-inch torpedo tubes: four installed in the bow; one installed in the stern. Fourteen torpedoes were carried. One 4-inch/50 caliber deck gun was installed forward of the conning tower. The full load of diesel oil carried was 36,950 gallons, which fueled two 1,000 designed brake horsepower MAN (Maschinenfabrik-Augsberg-Nurnberg) type diesel engines manufactured by the New York Navy Yard at Brooklyn, New York…which could drive the boat, via a direct drive propulsion system, at 15 knots on the surface in relatively calm seas. Power for submerged propulsion was provided by a main storage battery, divided into two sixty-cell batteries, manufactured by the Electric Storage Battery Company (EXIDE) at Philadelphia, Pennsylvania … which powered two 600 designed brake horsepower main propulsion motors manufactured by the Westinghouse Electric Company at Pittsburgh, Pennsylvania … which turned propeller shafts…which turned propellers…which could drive the submarine at 11 knots for a short period of time when operating beneath the surface of the sea. Slower submerged speeds resulted in greater endurances before the batteries needed to be recharged by the engines and generators.
Following commissioning, USS S-12 (SS-117) operated off the Northeast coast of the United States during the years 1923 and 1924.
The submarine also made a visit to Guantanamo Bay, Cuba, during the period 19 to 24 April 1924.
On 15 November 1924, USS S-12 commenced a transit, via the Panama Canal and California, from the United States Naval Submarine Base at New London/Groton, Connecticut, to the Territory of Hawaii…where she arrived on 24 April 1925. On 25 May 1925, the S-boat commenced a transit back to New London/Groton…and arrived at the submarine base on 12 July 1925.
In addition to service in the northeast coastal waters of the United States through 1928, USS S-12 operated in the approaches to the Panama Canal from January through April of 1926; visited Kingston, Jamaica, from 20 to 28 March of 1927; and served, again, in the coastal waters of the Panama Canal Zone from February into April of 1928.
From 1929 into 1936, USS S-12 operated almost exclusively in the waters adjacent to the Panama Canal Zone…although she visited Baltimore, Maryland, from 15 May to 5 June in 1933; and New London/Groton, Connecticut, from 15 May to 1 June in 1935.
Departing Coco Solo in the Panama Canal Zone on 13 June 1936, the S-boat transited to the Philadelphia Navy Yard at Philadelphia, Pennsylvania, and, upon arrival, commenced preparations for going out of service. On 30 September 1936, USS S-12 (SS-117) was decommissioned and placed in the reserve fleet at the Philadelphia Navy Yard.