On 15th of May 1957 Great Britain tested its first hydrogen bomb near Christmas Island in the Indian Ocean.

There were to be three tests, named Grapple 1, Grapple 2 and Grapple 3.

 Local people were forced from their homes, at best; or were left in place potentially to be exposed to ionising radiation, at worst…About 20,000 British servicemen, 524 New Zealand soldiers and 300 Fijian soldiers were deployed to “Christmas Island” from 1956 to 1962. These men were unwittingly placed in harsh conditions with limited resources, while undertaking the work that would cement Britain’s place in history as a thermonuclear power.

The atomic history of Kiritimati – a tiny island where humanity realised its most lethal potential

All bombs were dropped and detonated over Malden Island, and exploded high in the atmosphere.

The Grapple 1 mission was flown by Wing Commander Kenneth Hubbard, in XD818, with Squadron Leader Barney Millett in XD824 as the “grandstand” observation aircraft.. The two bombers took off from Christmas Island at 09:00. The bomb was dropped from 45,000 feet (14,000 m) off the shore of Malden Island at 10:38 local time on 15 May 1957. Hubbard missed the target by 418 yards (382 m). The bomb’s yield was estimated at 300 kilotonnes of TNT (1,300 TJ), far below its designed capability.

Despite its failure, the Grapple 1 test was hailed as a successful thermonuclear explosion. The UK had become a third thermonuclear power in the world.