The Heavy Press Program was a Cold War-era program of the United States Air Force to build the largest forging presses and extrusion presses in the world. These machines greatly enhanced the US defense industry's capacity to forge large complex components out of light alloys such as magnesium and aluminium. The program began in 1950 and concluded in 1957 after construction of four forging presses and six extruders, at an overall cost of $279 million. Eight of them are still in operation today, manufacturing structural parts for military and commercial aircraft. They still hold the records for size in North America, though they have since been surpassed by presses in Japan, France, Russia and China.