USS Sea Dog (SS-401/AGSS-401) was a Balao-class submarine in the United States Navy. She was the first ship to be named for the dogfish, a small shark of the North Atlantic, considered destructive by fishermen. Sea Dog was laid down on 1 November 1943 at the Portsmouth Navy Yard in Kittery, Maine. She was launched on 28 March 1944 sponsored by Mrs. Claire Dowden Lowrance, wife of the prospective commanding officer, and commissioned on 3 June 1944 with Commander Vernon L. Lowrance in command. Following a month's training off the New England coast, Sea Dog sailed for Pearl Harbor to join Submarine Squadron (SubRon) 28 and prepare for her first war patrol. Arriving in Hawaii on 22 August, she sailed west on 13 September, topped off at Midway Island on 17 September; and entered her patrol area in the Nansei Shoto on 28 September. First War Patrol With daylight traffic routed well inshore, she hunted unsuccessfully in the Kikaijima, Amami O Shima, and Okinoerabujima areas for the first few days, then searched the likely traffic lanes to Naha and Unten Ko. By 3 October, she had rounded Okinawa to patrol in the approaches to Nakagusuku Wan, and, by 6 October, she was again northwest of Okinawa in the Iheya Jima area. Sea Dog remained west of Okinawa for another five days but found no targets worthy of a torpedo. On 10 October, however, she took an armed trawler under fire and left it burning. On 11 October, she headed back into the Amami Gunto. A week later, she moved north into the Tokara Gunto and, on 22 October, while between the islands of Suwanosejima and Nakanoshima (Kagoshima), she sighted a convoy making eight to nine knots and zigging every five minutes. Sea Dog moved ahead of the port column and, at 0726, fired as two cargo ships overlapped in a zig. A minute later, she lost depth control and dropped to . Shortly after 0728, three loud explosions were heard. At 0732, the convoy's escorts began dropping depth charges. At 0745, breaking up noises were heard; and, at 0800, there was a dull, heavy explosion. Converted gun boat Tomitsu Maru and collier Muroto had been sunk. Depth charging continued for another two hours. In total, Japanese escorts and aircraft fired 109 depth charges at the Sea Dog, but LtCdr. Lowrance manages to evade the attack. Sea Dog continued to patrol