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FRUPAC Proves

Its Worth


After the attack on Pearl Harbor, Japanese submarines seemed to be active everywhere. On January 11, 1942, the aircraft carrier Saratoga was torpedoed by the Japanese submarine I-6, about 420 nautical miles southwest of Pearl Harbor. She was hit in the port side of her hull and the damage from the explosion forced her to return to Pearl Harbor for temporary repairs. On February 9, 1942, she sailed for the Bremerton Navy Yard in Puget Sound for permanent repairs. On January 23, 1942, the Japanese submarine I-172 torpedoed and sank the oiler USS Neches after she departed Pearl Harbor to support a task force organized to bombard Wake. The Neches was the only oiler available in the central Pacific and her loss forced cancellation of the operation. Thanks to U.S. naval intelligence operations, there were some successes. In late January 1942, the Fleet Radio Unit Pacific (FRUPAC) intercepted radio communications indicating that a group of Japanese submarines returning to Japan from the New Britain area were converging on the Midway islands to conduct a night bombardment of facilities there. The Marines on the islands were forewarned of their plans and the submarines’ gunfire was returned so rapidly and accurately that they ceased fire and submerged. On January 27, 1942, the first American submarine to make a patrol in Empire waters, USS Gudgeon (SS-211), was returning to Pearl Harbor via Midway. Her captain, Elton W. Grenfell, was also alerted of the danger by FRUPAC. That day Grenfell caught the submarine I-73 on the surface and made a cautious submerged approach. He fired three Mark 14 steam torpedoes from 1,800 yards and scored two hits, sinking the 1,400-ton Japanese submarine at 28° 23′ 60″ N, 178° 35′ 00″ E.

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