Tube Alloys - Post-war

Post-war

The Atomic Energy Research Establishment (AERE or the Harwell Laboratory) near Harwell, Oxfordshire was established by John Cockcroft in 1946 as the main centre for military and civilian atomic energy research and development in Britain. Former RAF bases were selected for AERE and AWRE as they were isolated, with large hangars. Hans von Halban was invited back to the UK by Frederick Lindemann (Lord Cherwell) to lead a team at the nearby Clarendon Laboratory in Oxford University, and worked there for eight years until 1955.

William Penney returned from the United States and appointed for the professorship (for Mathematics) at the Imperial College. Rather, Penney accepted the directorship position at the Armament Research Department (ARD) in 1946.

At the end of the war the British government had blindly trusted and thusly believed that America would share the (nuclear) technology, which the British saw as a joint discovery. However, the passing of the McMahon Act (Atomic Energy Act) by the President Harry Truman and his administration in August 1946, made it clear that Great Britain would no longer be allowed access to United States' atomic research. This partly resulted from the arrest for espionage of Alan Nunn May in 1946. On January 8, 1947, British PM Clement Attlee formed a secret "GEN.163 Cabinet committee", consisting of six civilian ministers of his government, charged with proceeding the efforts for Britain's nuclear progamme.

Prime Minister Clement Attlee's government decided that Britain required the atomic bomb to maintain its position in world politics. In the words of Foreign Secretary Ernest Bevin - "That won't do at all .. we've got to have this .. I don't mind for myself, but I don't want any other Foreign Secretary of this country to be talked to or at by a Secretary of State in the United States as I have just had in my discussions with Mr Byrnes. We've got to have this thing over here whatever it costs .. We've got to have the bloody Union Jack on top of it." Penney did not have any knowledge of such committee until he was approached by Charles Portal, Marshal of the Air Force as well as the Chief of the Air Staff of the Royal Air Force, to lead the clandestine efforts.

The project was code-named High Explosive Research (or HER). In May 1947, Penney was appointed as the director to lead the programme, based at the Royal Armament Research Development Establishment (RARDE) at Fort Halstead and the Royal Arsenal at Woolwich (AWE). In short span of time, Penney assembled a team to initiate the work on atomic weapons, firstly preparing a report on describing the feature, science and idea of the U.S. plutonium implosion bomb (codename Fat Man). Penney broke down the development tasks required to replicate it, and identifying outstanding questions that required further research on nuclear weapons. The report entitled, "Plutonium Weapon - General Description" was roughly equivalent in terms of scientific data and reports that were provided to Soviet Union for their nuclear program by Klaus Fuchs.

In April 1950 an abandoned World War II airfield, RAF Aldermaston in Berkshire was selected as the permanent home for Britain's nuclear weapons programme. This was to become the Atomic Weapons Research Establishment (AWRE). On 3 October 1952, under the code-name "Operation Hurricane", the first British nuclear device was successfully detonated off the west coast of Australia in the Monte Bello Islands. In 1958 the US-UK Mutual Defence Agreement was signed, providing for resumed nuclear weapons cooperation with the United States.