Operation Grapple: The Race to Build an H-Bomb | History Hit

Operation Grapple: The Race to Build an H-Bomb

One of the mushroom clouds generated by the Operation Grapple tests in 1957.
Image Credit: Public Domain / Royal Air Force

The first nuclear bomb was detonated in the New Mexico desert in July 1945: a weapon of previously unimaginable destruction which would go on to shape much of the politics and warfare of the rest of the 20th century.

As soon as it became apparent America had successfully created and tested nuclear weapons, the rest of the world began a desperate race to develop their own. In 1957, Britain began a series of nuclear weapons tests on small islands in the Pacific Ocean in an attempt to discover the secret to making a hydrogen bomb.

Why did it take Britain so long?

Throughout the 1930s, major scientific discoveries relating to nuclear fission and radioactivity were being made, particularly in Germany, but with the outbreak of war in 1939, many scientists fled, already becoming aware of the potential power of their discoveries in a weapons-based context. Britain invested money in research for the early part of the war, but as it dragged on, it became increasingly clear they did not have the ability to continue doing so financially.

Britain, American and Canada had signed the Quebec Agreement in 1943 in which they agreed to share nuclear technology: effectively meaning America agreed to continue funding nuclear research and development with the help of British scientists and research. Subsequent revisions curtailed this and the discovery of a Canadian spy ring which included a British physicist seriously damaged the nuclear ‘special relationship’ and set Britain back considerably in its quest to develop nuclear weapons.

Dr Becky Alexis Martin spoke to James about the lasting impacts of nuclear weapons testing.
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Operation Hurricane

America’s development and understanding of nuclear weapons and technology advanced rapidly and they became increasingly isolationist. Simultaneously, the British government became more and more concerned about their lack of nuclear weapons, deciding that in order to retain their status as a great power, they would need to invest more heavily in a nuclear weapons testing programme.

‘High Explosive Research’, as the project was now termed, was eventually successful: Britain detonated its first atomic bomb in 1952 in the Monte Bello islands in Western Australia.

Australia was still closely linked to Britain and hoped that by ceding to the request, the road to future collaboration on nuclear energy and potentially weapons might be paved. Very few people from Britain or Australia were privy to the explosion.

The bomb was exploded underwater: there were concerns of a dramatic tidal surge, but none occurred. It did, however, leave a crater on the seabed 6m deep and 300m across. With the success of Operation Hurricane, Britain became the third nation in the world to have nuclear weapons.

Front page of West Australian newspaper from 4 October 1952.

Image Credit: Public Domain

What next?

Whilst Britain’s achievement was a significant one, the government were still fearful of lagging behind the Americans and Soviets. Just a month after the first British successful testing of nuclear weapons, the Americans tested thermonuclear weapons which were considerably more powerful.

In 1954, the Cabinet announced their desire to see Britain successfully test thermonuclear weapons. Work began at a research facility named Aldermaston under Sir William Penney to try and develop this. At this point, knowledge of nuclear fusion in Britain was rudimentary, and in 1955, the Prime Minister, Anthony Eden, agreed that if inadequate progress was made, Britain would try and save face by simply detonating an extremely large fission bomb in an attempt to fool onlookers.

Operation Grapple

In 1957, Operation Grapple tests began: this time they were based on the remote Christmas Island in the Pacific Ocean. Three types of bombs were tested: Green Granite (a fusion bomb which didn’t produce a big enough yield), Orange Herald (which generated the largest fission explosion ever) and Purple Granite (another prototype fusion bomb).

A second round of tests in September of the same year was significantly more successful. Having seen how their previous bombs had exploded and the yields each type had generated, scientists had plenty of ideas of how best to create yields of over a mega-tonne. The design this time was much simpler, but had a much more powerful trigger.

On 28 April 1958, Britain finally dropped a true hydrogen bomb, one whose 3 megatonne explosive yield largely came from its thermonuclear reaction rather than fission. Britain’s successful detonation of a hydrogen bomb led to a renewed co-operation with the United States, in the form of the US-UK Mutual Defence Agreement (1958).

Dan sat down with Julie McDowall to talk about Britain's plans in case of nuclear Armageddon during the Cold War. They also discuss the nuclear disaster at Chernobyl and its infamous legacy.
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Many of those involved in the nuclear testing programme in 1957-8 were young men on National Service. The effects of radiation and nuclear fallout were still not completely understood at the time, and many of the men involved did not have adequate protection (if any) against radiation. Many were not even aware before they arrived of what was happened on Christmas Island.

A significant proportion of these men suffered the effects of radiation poisoning in subsequent years, and in the 1990s, several men sued for damages in a case which split the European Court of Human Rights. Those affected by the radioactive fallout of Operation Grapple have never received compensation from the UK government.

In November 1957, shortly after the earliest part of Operation Grapple, the Campaign for Nuclear Disarmament was founded in Britain. This organisation campaigned for unilateral nuclear disarmament, citing the terrible destructive power of nuclear weapons, which ultimately could not be used in warfare without leading to potential annihilation. Possession of nuclear weapons remans a hotly debated, and often controversial, topic today.

Sarah Roller