It was a just few weeks since the first and only nuclear weapon test yet conducted. The Little Boy bomb had been immediately dispatched to the Pacific theatre by the USS Indianapolis. The final decision on its use had ben taken by President Truman during the Potsdam conference.

Colonel Paul Tibbets had practiced the special procedure for dropping the bomb in the B-29 bomber. On 5th August he selected the aircraft to undertake the mission and decided to name it after his mother, Enola Gay – it was then that the aircraft was given the simple nose art that was to make it so famous.

After a six hour flight from Tinian island in the Pacific to the port of Hiroshima on the Japanese mainland. Then it became a simple technical process, beginning with an eleven minute bomb run:

Up to this point it was common practice in any theatre of war to fly straight ahead, fly level, drop your bombs, and keep right on going, because you could bomb several thousands of feet in the air and you could cross the top of the place that you had bombed with no concern whatsoever.

But it was determined by the scientists that, in order to escape and maintain the integrity of the aircraft and the crew, that this aeroplane could not fly forward after it had dropped the bomb. It had to turn around and get away from that bomb as fast as it could. If you placed this aeroplane in a very steep angle of bank to make this turn, if you turned 158 degrees from the direction that you were going, you would then begin to place distance between yourself and that point of explosion as quickly as possible.

You had to get away from the shock wave that would be coming back from the ground in the form of an ever expanding circle as it came upwards. It’s necessary to make this turn to get yourself as far as possible from an expanding ring and 158 degrees happened to be the turn for that particular circle.

It was difficult. It was something that was not done with a big bomber aeroplane. You didn’t make this kind of a steep turn — you might almost call it an acrobatic manoeuvre — and the big aircraft didn’t do these things. However, we refined it, we learned how to do it.

It had been decided earlier that there was a possibility that an accident could occur on take-off, and so therefore we would not arm this weapon until we had left the runway and were out to sea. This of course meant that had there been an accident there would have been an explosion from normal powder charges but there would not have been a nuclear explosion.

As I said this worried more people than it worried me because I had plenty of faith in my aeroplane. I knew my engines were good. We started our take-off on time which was somewhere about two-forty-five I think, and the aeroplane went on down the runway. It was loaded quite heavily but it responded exactly like I had anticipated it would. I had flown this aeroplane the same way before and there was no problem and there was nothing different this night in the way we went.

We arrived over the initial point and started in on the bomb run which had about eleven minutes to go, rather a long type of run for a bomb but on the other hand we felt we needed this extra time in straight and level flight to stabilize the air speed of the aeroplane, to get everything right down to the last-minute detail.

As I indicated earlier the problem after the release of the bomb is not to proceed forward but to turn away. As soon as the weight had left the aeroplane I immediately went into this steep turn and we tried then to place distance between ourselves and the point of impact. In this particular case that bomb took fifty-three seconds from the time it left the aeroplane until it exploded and this gave us adequate time of course to make the turn.

We had just made the turn and rolled out on level flight when it seemed like somebody had grabbed a hold of my aeroplane and gave it a real hard shaking because this was the shock wave that had come up. Now after we had been hit by a second shock wave not quite so strong as the first one I decided we’ll turn around and go back and take a look.

The day was clear when we dropped that bomb, it was a clear sunshiny day and the visibility was unrestricted. As we came back around again facing the direction of Hiroshima we saw this cloud coming up. The cloud by this time, now two minutes old, was up at our altitude. We were 33,000 feet at this time and the cloud was up there and continuing to go right on up in a boiling fashion, as if it was rolling and boiling.

The surface was nothing but a black boiling, like a barrel of tar. Where before there had been a city with distinctive houses, buildings and everything that you could see from our altitude, now you couldn’t see anything except a black boiling debris down below.