USS S-4 (SS-109) - Service

Service

Following acceptance trials, a visit to Havana, Cuba from 14-19 January 1920, and subsequent operations along the Gulf of Mexico and New England coasts, S-4 departed New London, Connecticut on 18 November to rendezvous off New Hampshire with her assigned unit — Submarine Divisions 12 (SubDiv 12) — and SubDiv 18. The two divisions were about to embark on a historic voyage which, at that time, was to be the longest cruise undertaken by American submarines. Assigned to Submarine Flotilla 3 of the Asiatic Fleet at Cavite in the Philippine Islands, they sailed via the Panama Canal and Pearl Harbor and arrived at Cavite on 1 December 1921.

S-4 operated out of the Cavite Naval Station, with occasional visits to Chinese ports, until late 1924, when the two divisions were reassigned to the West Coast. Departing Cavite on 29 October, they arrived at Mare Island, California on 30 December.

Remaining at Mare Island in 1925, she operated along the West Coast through 1926, mainly at San Francisco, San Pedro, and San Diego. She departed Mare Island on 10 February 1927 and sailed to the Panama Canal Zone, where she operated through March-April, then proceeded to New London, Connecticut, arriving on 3 May. For the remainder of the year, she operated off the New England coast.