Nuclear Weapons and The United Kingdom - Weapons Tests

Weapons Tests

The United Kingdom independently tested its first nuclear weapon 'Hurricane' on 3 October 1952, on the Montebello Islands off the coast of Western Australia. Seven further nuclear tests were held at Emu Fields and Maralinga between 1955 and 1963.

The first British hydrogen bombs were tested during Operation Grapple at Malden Island and Christmas Island in the Central Pacific Ocean. The operation consisted of nine tests in the period 1957-1959, ultimately proving that the UK had developed thermonuclear weapons.

Different sources give the total number of test explosions that the UK has conducted as either 44 or 45. The 24 tests from December 1962 onwards were in conjunction with the United States at the Nevada Test Site with the final test being the Julin Bristol shot which took place on 26 November 1991.

Because Britain did not test as often as the United States due to financial and political reasons British weapons design depended more on theoretical understanding, with potential for both greater advances and risks between tests. The low numbers of UK tests is misleading when compared to the large numbers of tests carried out by the US, the Soviet Union, China, and especially France; because the UK has had extensive access to US test data, obviating the need for UK tests: and an added factor is that many tests required are for 'weapon effects tests'; tests not of the nuclear device itself, but of the nuclear effects on hardened components designed to resist ABM attack. Numerous such 'effects' tests were done in support of the Chevaline programme especially; and there is some evidence that some were permitted for the French programme to harden their RVs and warheads; because most French tests being under the ocean floor, access to measure 'weapon effects' was nigh impossible. An independent test programme would see the UK numbers soar to French levels.

The UK government signed the Partial Test Ban Treaty on 5 August 1963 along with the United States and the Soviet Union which effectively restricted it to underground nuclear tests by outlawing testing in the atmosphere, underwater, or in outer space. The UK signed the Comprehensive Test Ban Treaty on 24 September 1996 and ratified it on 6 April 1998, having passed the necessary legislation on 18 March 1998 as the Nuclear Explosions (Prohibition and Inspections) Act 1998.