After a week of drills, Atule departed Pearl Harbor on 3 July 1945 bound for a lifeguard station in the Nanpo Shoto. After nine days with little action, the submarine proceeded to her patrol area in Empire waters east of Honshu as part of an attack group which also included Gato and Archerfish (SS-311). On 12 August, Atule gained contact on two ships, later identified as Coast Defense Vessel No. 6 and Coast Defense Vessel No . 16, steaming along the coast. Shallow waters and poor visibility caused Atule to set a course to intercept in the vicinity of Urakawa Ko rather than to attack the contacts under such adverse conditions. With the targets overlapping, Atule fired six torpedoes. The closer of the two ships-Coast Defense Vessel No. 6-exploded with an orange flame and much flying debris. The second target disappeared from radar, but it is not known whether she sank or escaped. On 15 August, Atule heard the news of the Japanese capitulation and headed via Midway for Pearl Harbor where she arrived on 25 August. On 30 August, she departed Pearl Harbor via the Panama Canal, bound for New London, Conn.