Theordore Van Kirk suddenly felt the Enola Gay surge upward as their nine-hundred-pound bomb left the bomb bay. “Immediately Paul switched off the autopilot and started to go into the turn to get away from it—160 degrees to the right. Steep as you can make it. Pushed the throttles all forward, put the nose down to get enough speed to get away in the forty-three seconds at which the bomb would reach its altitude where it would explode.”
Little Boy hurtled toward earth, heading for the Aioi Bridge. At five miles down, the bomb’s fin radar system activated the detonator. At 8:15 AM, some forty-three seconds after Ferebee had dropped it from the Enola Gay’s bomb bay, the weapon exploded at 1,890ft above the ground. Tibbets and his crew were by then approximately six miles away, having turned away as instructed by Oppenheimer. Ferebee’s aim, however, had been off, missing the bridge by approximately eight hundred feet. The atomic bomb detonated instead above the Shima Surgical Hospital. It didn’t matter for the men, women, and children of Hiroshima within the blast radius; the effect would be the same.
Van Kirk recalled, “Everyone in the airplane didn’t have a watch, they were counting, ‘1001, 1002, 1003, etc.’ I think we had concluded it was a dud, as it seemed to be a long forty-three seconds. Then suddenly, there was a bright flash in the air and very shortly after, the first shockwave hit the Enola Gay. The sound was worse than the shockwave. It sounded like a piece of sheet metal snapping. Somebody onboard [mistakenly] called out ‘flak!’ but George Caron in the tail gunner’s position confirmed it was a shockwave, and another one was about to strike, though less intensity than the first.
“It was then that Bob Lewis [exclaimed] second statement in the log [probably once he got on the ground at Tinian—‘My God, what have we done?’—it was a better quote]. What he actually said in the aircraft was: ‘Look at that son of a bitch go!’”
Aboard the Necessary Evil, Russell Gackenbach felt the sonic boom. “The echo just bounced off the nose of our plane because of streamlining. The other two planes were heading away from the blast, so their tails felt the blast. As a result, [the Enola Gay] were rocking for a little while until their tail gunner says, ‘Here comes another sonic bomb.’”