Trident (UK nuclear programme) Agreement merged with the American Manhattan Project to create a combined American, British, and Canadian project. The British government expected that the United States would continue to share nuclear technology, which it regarded as a joint discovery, but the United States Atomic Energy Act of 1946 (McMahon Act) ended technical co-operation. Fearing a resurgence of United States isolationism, and Britain losing its great power status, the British government resumed its own development effort. The first British atomic bomb was tested in Operation Hurricane on 3 October 1952. The subsequent British development of the hydrogen bomb, and a fortuitous international relations
Soviet atomic bomb project CIA. RDS-3 was the third Soviet atomic bomb. On October 18, 1951, the 41.2 kiloton device was detonated - a boosted weapon using a composite construction of levitated plutonium core and a uranium-235 shell. Code named "Joe 3" in the USA, this was the first Soviet air-dropped bomb test. Released at an altitude of 10 km, it detonated 400 meters above the ground. RDS-4 represented a branch of research on small tactical weapons. It was a boosted fission device using plutonium in a "levitated" core design. The first test was an air drop on August 23, 1953, yielding 28 kilotons.