Both the Trinity test and Fat Man were implosion type weapons: http://en.wikipedia.org/wiki/Nuclear_weapon_design#Implosion-type_weapon http://en.wikipedia.org

Both the Trinity test and Fat Man were implosion type weapons: http://en.wikipedia.org/wiki/Nuclear_weapon_design#Implosion-type_weapon http://en.wikipedia.org/wiki/Nuclear_weapon_design#Implosion... I don't think Little Boy's design was tested prior to being dropped on Hiroshima.