Japanese navy admiral and one of the planners of the raid on U.S. forces at Pearl Harbor. Born in Tokyo on 25 September 1892, Kusaka Ryunosuke graduated from the Naval Academy in 1913. He was one of the early specialists in naval aviation in the Japanese navy and served as an instructor at the Kasumigaura Naval Air Station and the Naval War College in 1924. In August 1929, Kusaka traveled on the German airship Graf Zeppelin across the Pacific Ocean. He served on the Navy General Staff in 1929 and was promoted to commander in 1930. Made captain in 1934, he then commanded the aircraft carriers Hosho in 1936 and Akagi in 1939.

Promoted to rear admiral in 1940, Kusaka served as chief of staff of the First Air Fleet and helped to plan the attack on Pearl Harbor. He also assisted the commander of the Combined Fleet, Admiral Yamamoto Isoroku, plan the attack on Midway. He participated in this operation as chief of staff of the First Air Fleet.

Kusaka fought in the October 1942 Battle of the Santa Cruz Islands during the Guadalcanal Campaign as chief of staff of the Third Fleet. In 1944, he became chief of staff of the Combined Fleet under Admiral Toyoda Soemu, participating in the Battles of the Philippine Sea and Leyte Gulf. At the very end of the war, in August 1945, he was appointed commander of the Fifth Air Fleet. Kusaka died at Hyogo, Japan, on 23 November 1971.

Kotani Ken

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Further Reading
Evans, David C., and Mark R. Peattie. Kaigun: Strategy, Tactics and Technology in the Imperial Japanese Navy, 1889–1941. Annapolis, MD: Naval Institute Press, 1997.; Kusaka, Ryunosuke. Ichi Kaigunshikan no Hanseiki (Life of a naval officer). Tokyo: Kowado, 1973.