When U.S. codebreakers intercepted Admiral Isoroku Yamamoto's flight itinerary on April 14, 1943, they handed the Pacific Fleet a weapon more precise than any bomb: knowledge. On April 18, eighteen P-38 Lightnings of the 339th Fighter Squadron launched from Guadalcanal's Henderson Field, fitted with oversized 330-gallon drop tanks for the 1,000-mile round trip. Flying at wave-top level to avoid detection, they reached Bougainville at exactly 0934—the moment Yamamoto's G4M "Betty" bomber arrived. In the ensuing melee, both Japanese bombers were shot down. Yamamoto's body was found still strapped in his seat, clutching his samurai sword. It was the first time in history a military had deliberately targeted and killed an individual enemy commander by air. The P-38, already the most feared American fighter in the Pacific, had earned its place in the history of aerial assassination.