Deep Dives 11 (WikiLeaks Archive) – The Penney Report and How Britain Got the Bomb

I was recently looking into the nuclear programs of different nation states and was intrigued by a WikiLeaks page file named ‘United Kingdom atomic weapons program: The full Penney Report (1947)’ after specifically looking for more information on the British programme, by inputting the phrase ‘How Britain Got the Bomb’ into the search function. The resultant page file also includes an interesting email exchange between staff members from WikiLeaks and the Foreign and Commonwealth Office in the UK, over the publishing of this information on the WikiLeaks website.

In many ways the British scientific establishment was arguably more advanced in the theory and possible development of the atom bomb and conducted early research into the possibility and feasibility of such an exercise. This research was conducted by the formation of a scientific working group called the MAUD committee. Part of the 1941 report by the MAUD Committee and its general conclusions, can be found here at atomicarchive.com.

Here is an excerpt which shows the known implications and ramifications of building such a weapon well in advance of it being constructed:

We should like to emphasize at the beginning of this report that we entered the project with more skepticism than belief, though we felt it was a matter which had to be investigated. As we proceeded we became more and more convinced that release of atomic energy on a large scale is possible and that conditions can be chosen which would make it a very powerful weapon of war. We have now reached the conclusion that it will be possible to make an effective uranium bomb which, containing some 25 lb of active material, would be equivalent as regards destructive effect to 1,800 tons of T.N.T. and would also release large quantities of radioactive substance, which would make places near to where the bomb exploded dangerous to human life for a long period. The bomb would be composed of an active constituent (referred to in what follows as -U) present to the extent of about a part in 140 in ordinary Uranium. Owing to the very small difference in properties (other than explosive) between this substance and the rest of the Uranium, its extraction is a matter of great difficulty and a plant to produce 2-4 lb (1 kg) per day (or 3 bombs per month) is estimated to cost approximately 95,000,000 pounds, of which sum a considerable proportion would be spent on engineering, requiring labour of the same highly skilled character as is needed for making turbines.

In spite of this very large expenditure we consider that the destructive effect, both material and moral, is so great that every effort should be made to produce bombs of this kind. As regards the time required, Imperial Chemical Industries after consultation with Dr. Guy of Metropolitan--Vickers, estimate that the material for the first bomb could be ready by the end of 1943. This of course assumes that no major difficulty of an entirely unforeseen character arises. Dr. Ferguson of Woolwich estimates that the time required to work out the method of producing high velocities required for fusing (see paragraph 3) is 1-2 months. As this could be done concurrently with the production of the material no further delay is to be anticipated on this score. Even if the war should end before the bombs are ready the effort would not be wasted, except in the unlikely event of complete disarmament, since no nation would care to risk being caught without a weapon of such decisive possibilities.
         

These are the conclusions and recommendations at the end of the report:

(i) The committee considers that the scheme for a uranium bomb is practicable and likely to lead to decisive results in the war.

(ii) It recommends that this work be continued on the highest priority and on the increasing scale necessary to obtain the weapon in the shortest possible time.

(iii) That the present collaboration with America should be continued and extended especially in the region of experimental work.

This research and development into constructing an atom bomb, ‘officially’ started during World War II, which was a highly secretive and clandestine project codenamed ‘Tube Alloys’, and as such the project and its details were strictly classified at the time. Eventually the Tube Alloys project was merged and subsumed into the Manhattan Project, after the Quebec Agreement was reached between Britain, The United States and Canada, where they signed an agreement to pool their resources into a joint effort to produce the bomb.

William George Penney was a highly regarded physicist (an expert in ocean waves) in British scientific circles and was an integral part of, and head of the British delegation who contributed importantly to the much wider known and publicised nuclear programme of the United States, in the Manhattan Project at the Los Alamos National Labaratory. His expertise in his particular field was quickly noticed during his time at the Manhattan Project, and he was elevated in prominence and included as part of the inner circle of five, dubbed the ‘brains trust’ of Los Alamos. One of Penney’s unclassified reports on the optimal height of a nuclear explosion to cause maximum damage, can be found here.

This was also a position that resulted in Penney being a direct witness (from a plane), to the atomic bombing of Nagasaki during WWII.

blog.nuclearsecrecy.com

At the successful completion of the Manhattan Project and to the bemusement of the British establishment, The United States then refused to share all of its nuclear secrets with Britain, some of which they withheld throughout the process of constructing the bomb. Britain felt betrayed that the United States had broken the so-called special relationship they enjoyed to that point in time with its main ally. For this reason, the British were determined to create their own independent nuclear project in an endeavour to create its own bomb and remain in the league of the most powerful nations…and at any cost.

The new secret project, now called High Explosive Research was commissioned by the British government, directed by Charles Portal and William Penney was asked to head a scientific team in charge of bomb design, which would see the British constructing and testing its own bomb. It is during this time that William Penney, wrote The Penney Report. For this reason, Penney is widely acknowledged as being the ‘father of the British atom bomb’.

The Penny Report outlined the features of an atomic bomb based on the U.S Fat man pattern, and the tasks required to develop a working atom bomb as part of the British nuclear programme, including the illustrative diagram below.

WikiLeaks.org

Due to the expertise of William Penney and his team of scientists, the British were successful in reaching their goal of constructing their own bomb, and now it was time to conduct their first nuclear test in October of 1952, under the code name of Operation Hurricane.

historytoday.com

The test site was finally determined to be the uninhabited Montebello Islands, off the north-west coast of Australia. The tests were conducted by the Ministry of supply with close co-operation between the three armed forces and in full knowledge and co-operation of the Australian Prime Minister and its armed forces.

iwm.org.uk

At the conclusion of Britain’s first nuclear test, Winston Churchill informed the House of Commons that it was a successful operation, and Britain found itself as one of only three nations to successfully construct and test an atom bomb along with The United States and The Soviet Union.

Here is the archived video footage of Britain’s first atomic bomb test at the Montebello Islands: