Operation RY - First Invasion Attempt

First Invasion Attempt

On 11 May 1942, the Imperial Japanese invasion force, under the command of Rear Admiral Shima Kiyohide departed Rabaul consisting of the cruiser Tatsuta, the minelayers Okinoshima (flagship) and Tsugaru and destroyers Uzuki and Yuzuki, covered by 5th Cruiser Division, under the command of Rear Admiral Takeo Takagi, consisting of heavy cruisers Myoko and Haguro with the Destroyer Division 30 destroyers Ariake, Mochizuki, Shigure and Shiratsuyu. The invasion troops from the 6th Special Naval Landing Force (SNLF) and Kashima SNLF were carried by the transports Kinryū Maru and Takahata Maru.

While steaming through driving rain off New Ireland and west of Buka Island, Okinoshima, which had been damaged by planes from Yorktown during the invasion of Tulagi on 4 May 1942, was torpedoed at 0452 by the United States Navy submarine USS S-42 (Commander Oliver G. Kirk) and severely damaged. The invasion force's escorts closed S-42 and depth charged the area until 1130, causing damage. The submarine left the area to return to base at Moreton Bay, Brisbane. Rear Admiral Shima transferred his flag to Yuzuki southwest of Buka Island, Bougainville. At 0640, Okinoshima capsized under tow by Mochizuki in St. George's Channel at 05°06′S 153°48′E / 5.100°S 153.800°E / -5.100; 153.800.

While returning to Rabaul after being dispatched to assist repair work on Okinoshima, the repair ship Shoei Maru was torpedoed off Cape St George, New Ireland, by USS S-44. She sank at 1440 at 04°51′S 152°54′E / 4.850°S 152.900°E / -4.850; 152.900.

In spite of the loss of Okinoshima, the rest of the Japanese forces continued with the operation. As these forces were en route, however, a Japanese reconnaissance aircraft from Tulagi sighted the United States Navy aircraft carriers Enterprise and Hornet heading towards Nauru. The two US carriers, acting on intelligence taken from intercepted Japanese communications, had been sent to the area as a feint to try to stop the Japanese operation.

The feint was successful. Fearing the threat posed by the US carriers to the RY forces, which did not have air cover, the Japanese cancelled the operation on 15 May and the naval forces returned to Rabaul.