An engineering history of the Manhattan Project

The Manhattan Project was more than a science effort; it was an unprecedented industrial undertaking that transformed America into a massive production facility. Engineers faced extraordinary challenges producing fissile material, developing multiple bomb designs simultaneously, and inventing new machines and techniques under extreme wartime pressure. The project pursued parallel paths—using both uranium-235 and plutonium, different separation methods, and multiple bomb designs—while building massive facilities at Oak Ridge and Hanford before knowing what would work.