Sonic Boom Squadron.On August 5, 1945, a Japanese squadron of Betty bombers, each carrying an Ohka and escorted by A6M2 Reisen fighters, attempts a raid on an American aircraft carrier battle group in the Pacific Ocean. As the raiders are attacked by American carrier-based aircraft, Ensign Nogami, a young Ohka pilot, demands to be launched in his Ohka, even if it means he misses his target, but his Betty's crew refuses, and he is knocked out and tossed off the plane with a parachute. He awakens in time to watch his fleet explode before his very eyes. He returns to base, where he meets the crew of the Betty who will fly him on a mission the following day, as well as two surviving Reisen pilots who vow to help him succeed in his mission if it costs them their lives. On board the American carrier, the pilots receive news from their captain that the attacking Betties were carrying Ohkas which are much faster than their own F6F Hellcats. The next day, August 6, the Japanese attempt a second raid on the same battle group. An intense aerial dogfight ensues as the American carrier aircraft attempt to thwart the raiders from launching their Ohkas. Nogami begs his crew to cut him loose, but the plane isn't close to the American fleet just yet and holds off on letting him go. A US Navy Hellcat pursues Nogami's bomber, and inflicts serious damage, but the latter is saved by the intervention of one of the Reisen pilots, who crashes his aircraft into the Hellcat, destroying both planes. This enables the Betty to get within visual range of the battle group, and Nogami is launched in his Ohka just before the wing of the bomber disintegrates and explodes. He flies through a wall of anti-aircraft fire thrown up by the escorting vessels and crashes into the American aircraft carrier. Just before the carrier's superstructure explodes, the battle group's commander receives word that an atomic bomb has just been dropped on Hiroshima.