There was some hesitation about an effort to intercept and shoot down Yamamoto's aircraft, stemming from concerns that the move might compromise U.S. code-breaking operations. Also, Yamamoto, though a superb officer, had proved to be a disaster as a strategist, which had worked to the advantage of the U.S. force. The order for the attack came from Secretary of the Navy Frank Knox through Admiral Chester Nimitz to Admiral Marc A. Mitscher, air commander in the Solomons area.
Mitscher assigned the mission to the Army Air Forces' 339th Fighter Squadron of the Thirteenth Air Force on Guadalcanal because of the long-range capability of its Lockheed P-38 Lightning fighters. The operation, code-named y-mission, was carefully planned and carried out at low altitude under radio silence to ensure surprise. Major John W. Mitchell, the squadron commander, led the 400-mile mission. The 16 aircraft that performed the mission conducted a successful flight and interception, arriving over Bougainville just as two Japanese G4M Betty medium bombers and six Mitsubishi A6M Reisen Zero fighter escorts approached to land at Kahili Field at Buin in southern Bougainville. Both Japanese bombers were shot down, along with three of the Zeros, and Yamamoto was killed. Captain Thomas G. Lanphier and Lieutenant Rex Barber shared the credit for downing Yamamoto's aircraft, although a debate over the actual pilot responsible for shooting down the plane continued after the war.
Jerome V. Martin
Agawa Hiroyaki. The Reluctant Admiral: Yamamoto and the Imperial Navy. Ed. and trans. James Besten. New York: Harper and Row, 1979.; Davis, Burke. Get Yamamoto. New York: Random House, 1969.; Glines, Carroll V. Attack on Yamamoto. Atglen, PA: Schiffer Publishing, 1993.