 Fat Man F31 was assembled on Tinian by Project Alberta personnel, and the physics package was fully assembled and wired.It was placed inside its ellipsoidal aerodynamic bombshell and wheeled out, where it was signed by nearly 60 people, including Purnell, Brigadier General Thomas F. Farrell, and Parsons.It was then wheeled to the bomb bay of the B-29 Superfortress named "Bockscar" after the plane's command pilot Captain Frederick C. Bock, who flew "The Great Artiste" with his crew on the mission.