Operation Greenhouse (1951)

"This test took place in the spring of 1951. It was carried out by the 8500 members of Joint Task Force Three; men drawn from the Atomic Energy Commission, its contractors, military, industrial, and educational laboratories, and from the Army, Navy, and Air Force."

Operation GREENHOUSE was conducted in April and May of 1951.

This test series consisted of four weapons related test shots from the 300-foot level on towers on the Enewetak Atoll, Pacific Ocean, two of which greatly aided the pursuit of a hydrogen, or thermonuclear device.

Carried out by the Atomic Energy Commission, the shots were:

Dog, April 7, 81 kilotons
Easy, April 20, 47 kilotons
George, May 8, 225 kilotons
Item, May 24, 45.5 kilotons

The George experiment proved an thermonuclear bomb was possible and led to a crash development program of the "Super." The fusion contribution was roughly 25 kilotons equivalent yield.

Item was the first test of the boosting design principle, which involved increasing the yield of a fission implosion weapon. The effect often approximately doubled the yield for the same amount of fission fuel, effectively revolutionizing efficiency in weight versus yield of each warhead, excluding a dirty casing effects option of fast fission of uranium 238-lined weapon casings.