By Susan DeGrane

On August 6, 1945, the Enola Gay dropped a uranium bomb nicknamed Little Boy on Hiroshima, killing 150,000. Fat Man, the plutonium bomb that hit Nagasaki, was a more powerful device than Little Boy. But due to weather conditions in Nagasaki and its mountainous terrain, which blocked the blast, Fat Man killed fewer people. The exact number of deaths is unknown; published estimates range from 28,000 to 80,000. A memorial at the site is dedicated to 73,884 killed and 74,909 injured. Then there are the many who died years later of radiation poisoning.

Best of Chicago voting is live now. Vote for your favorites »

“A lot of the kids you see alive today wouldn’t be here if their grandfathers had been killed. So you see, a lot of good things came from the bombs.”

He wanted to publish his personal account partly to preserve history, but partly for other reasons. “Over the years there were rumors that the guys who flew the plane had all cracked up,” he told the audience. “We didn’t. We were fine. I wanted to set the record straight.”

“Taking off,” he said, “we knew we carried enough explosive power to blow up the entire island, the equivalent of 20,000 tons of TNT.” Tinian Island is 42 square miles, about twice the size of Manhattan. “We didn’t even use the word ‘atomic’ because so little was known about it,” Olivi told his listeners. “We called it the gadget, the gimmick. . . . To me it was mind-boggling to think this could blow up an entire city.”

At Kokura, clouds and smoke from incendiary bombs obscured visibility completely. The bombardier had specific orders to drop only when he could see the target, and after three unsuccessful runs, using up even more gas, the plane went on to its secondary target: Nagasaki. Fuel levels were already low, and a trip to Nagasaki meant the plane would not make it back to Tinian. They’d have to land at the air base at Okinawa.

Several days after bombing Nagasaki, Olivi and the crew were sent up again, this time to drop a conventional bomb over Koromo. This one was filled with Torpex, an explosive used in torpedoes. “No one wanted to go back up,” Olivi said. “We wanted the war to be over.” On August 15, within hours of the crew’s return from the Koromo assignment, they got the news that the war had ended.