USS S-43

USS S-43 (SS-154) was a third-group (S-42) S-class submarine of the United States Navy.

S-43′s keel was laid down on 13 December 1920 by the Bethlehem Shipbuilding Corporation's Fore River Shipyard in Quincy, Massachusetts. She was launched on 31 March 1923, sponsored by Mrs. John H. Brown, and commissioned on 31 December 1924.

Initially assigned to Submarine Division (SubDiv) 19 and then to SubDiv 11, S-43 completed trials off the Connecticut coast and, in April 1925, moved south to Guantanamo Bay. Thence, she proceeded to the Submarine Base, Coco Solo in the Panama Canal Zone, where she was based for the next two years. Engaged in exercises—individual, division, and fleet—during that period, she was transferred with her division to the Battle Force in July 1927 and based at San Diego, California. From there, she continued her schedule of exercises and fleet problems into the 1930s. Annual overhauls and exercises off southern California were followed by summer operations in Hawaiian waters and autumn patrols and exercises off Mexico.

December 1930, however, brought changes to her schedule. Then reassigned to Pearl Harbor, she operated almost exclusively in the Hawaiian area until 1941. Exceptions to these operations came with fleet problem deployment and inactive periods during her years, 1932 to 1935, in the rotating reserve.

In June 1941, the boats of SubDiv 11 were ordered to New London, Connecticut. There, the division was redesignated SubDiv 53, and the old S-boats were ordered, in groups, to Philadelphia, Pennsylvania, for overhaul and alterations to increase their reliability in case of war.

In August, S-43 put back to sea only to suffer a complete power failure which foreshadowed future breakdowns. In September, however, she assumed patrol and training duties out of Bermuda. At the end of October, she returned to southern New England for similar operations in the New London, Connecticut-Newport, Rhode Island area; and, in late November, she moved further north, to Newfoundland, to test the effects of weather there on the S-boats.

On 7 December, the United States entered World War II. The next day, S-43 departed the Canadian coast for New London and Coco Solo. On 27 December, she reached the Panama Canal Zone; and, on 9 January 1942, she transited the canal to conduct a security patrol in the Pacific approaches to that vital area. Returning to Coco Solo on 2 February, she prepared for transfer to the Australia-New Zealand area.

On 5 March, SubDiv 53, accompanied by submarine tender Griffin, got underway for Australia. In mid-April the S-boats completed their 12,000-mile voyage at Brisbane, Queensland, where they were joined by the Asiatic Fleet's S-boats to form TF 42.