The delivery program , codenamed Project Alberta , got underway under Ramsey 's direction in October 1943 . Starting in November , the Army Air Forces Materiel Command at Wright Field , Ohio , began Silverplate , the codename for the modification of B-29s to carry the bombs . Parsons arranged for a test program at Dahlgren using scale models of Thin Man and Fat Man . Test drops were carried out at Muroc Army Air Field , California and the Naval Ordnance Test Station at Inyokern , California using full-size replicas of Fat Man known as pumpkin bombs . The ungainly and non-aerodynamic shape of Fat Man proved to be the main difficulty , but many other problems were encountered and overcome . Parsons , wrote Oppenheimer , " has been almost alone in this project to appreciate the actual military and engineering problems which we would encounter . He has been almost alone in insisting on facing these problems at a date early enough so that we might arrive at their solution . " In July 1944 , Parsons joined Jack Crenshaw , who was investigating the Port Chicago disaster . The two men surveyed the disaster area , where 1,500 tons of munitions had exploded and 320 men had lost their lives . A year later , Parsons watched the Trinity nuclear test from a circling B-29 . Afterwards , Parsons flew to Tinian , where the B-29s of Colonel Paul W. Tibbets ' 509th Composite Group were preparing to deliver the weapons . En route , he stopped off in San Diego to visit his eighteen-year-old half-brother Bob , a marine who had been badly wounded in the Battle of Iwo Jima . Parsons also met with Captain Charles B. McVay III , the skipper of the cruiser , in Purnell 's office at the Embarcadero in San Francisco and gave McVay his orders : Parsons was in charge of scientists and technicians from Project Alberta on Tinian , who were nominally organized as the 1st Technical Service Detachment . Their role was the handling and maintenance of the nuclear weapons . Parsons was joined by Purnell , who represented the Military Liaison Committee , and Brigadier General Thomas F. Farrell , Groves ' Deputy for Operations . They became , informally , the " Tinian Joint Chiefs " , with decision-making authority over the nuclear mission . Before Farrell left for Tinian , Groves had told him : " Do n't let Parsons get killed . We need him ! " In the space of a week on Tinian , four B-29s crashed and burned on the runway . Parsons became very concerned . If a B-29 crashed with a Little Boy , the fire could cook off the explosive and detonate the weapon , with catastrophic consequences . He raised the possibility of arming the bomb in flight with Farrell , who agreed that it might be a good idea . Farrell asked Parsons if he knew how to perform this task . " No sir , I do n't " , Parsons conceded , " but I 've got all afternoon to learn . " The night before the mission , Parsons repeatedly practiced inserting the powder charge and detonator in the bomb in the poor visibility and cramped conditions of the bomb bay
Trinity nuclear test
Trinity (nuclear test)
William Sterling Parsons