The next break in the weather over Japan was due to appear just three days after the attack on Hiroshima , to be followed by at least five more days of prohibitive weather. The plutonium implosion bomb , nicknamed "Fat Man," was rushed into readiness to take advantage of this window. No further orders were required for the attack. Truman's order of July 25th had authorized the dropping of additional bombs as soon as they were ready.
At a. From this point on, few things went according to plan. The aircraft commander, Major Charles W. Sweeney, ordered the arming of the bomb only ten minutes after take-off so that the aircraft could be pressurized and climb above the lightning and squalls that menaced the flight all the way to Japan. A journalist, William L. Laurence of the New York Times , on an escorting aircraft saw some "St. Elmo's fire" glowing on the edges of the aircraft and worried that the static electricity might detonate the bomb.
Sweeney then discovered that due to a minor malfunction he would not be able to access his reserve fuel. The aircraft next had to orbit over Yaku-shima off the south coast of Japan for almost an hour in order to rendezvous with its two escort Bs, one of which never did arrive.
The weather had been reported satisfactory earlier in the day over Kokura Arsenal, but by the time the B finally arrived there, the target was obscured by smoke and haze.
Two more passes over the target still produced no sightings of the aiming point. As an aircraft crewman, Jacob Beser, later recalled, Japanese fighters and bursts of antiaircraft fire were by this time starting to make things "a little hairy.
