Pumpkin bomb

Pumpkin bombs were aerial bombs used in preparation for the use of the first atomic weaponry. Originally concrete dummy bombs, they mimicked the weight and size of the explosives nicknamed Fat Man and Little Boy that would be dropped on the cities of Hiroshima and Nagasaki. They were used to test the logistics of using atomic weaponry, like taking off, dropping the weapons, and escaping the blast safely without using atomic weaponry on American soil.  Although later pumpkin bombs contained high explosives and were used in practice aiming at targets in Japan, they never contained any plutonium. The nickname “Pumpkin Bomb” was earned from their large bulbous shape.