Kokura was the primary target for the Bockscar mission that ultimately bombed Nagasaki.
Bockscar took off from Tinian on August 9, 1945, carrying the Fat Man atomic bomb. The mission plan listed Kokura, an important industrial and military center, as the primary target. The crew made several attempts to find a clear visual approach, but cloud cover and smoke prevented the required bombing run.
With fuel running low, the aircraft diverted to Nagasaki, the secondary target. A brief break in the clouds allowed bombardier Kermit Beahan to identify the aiming point, and Fat Man was released at approximately 11:02 a.m. local time.
Kokura’s role created the later expression “Kokura’s luck,” referring to the city’s escape from the atomic attack because of weather and smoke. Kokura is often confused with Nagasaki because Nagasaki was the city actually struck during the mission.