The fourth war patrol of the USS Sennet (SS-408), under the captaincy of Lieutenant Commander Charles R. Clark, Jr., was conducted in the Sea of Japan during the period covering July 1, 1945 to August 9, 1945. The Sennet's principal area of coverage was off the northwest coast of Honshu and the west coast of Hakkaido. After only three days in her assigned area, all torpedoes were expended in six torpedo attacks. Eight enemy ships were contacted in a 72.5-hour period. All were attacked and four of them were sunk. The Sennet was equipped with the latest mine detection sonar. She entered the Sea of Japan via the Tsushima Strait and exited it via the La Perouse Strait.
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