Operation Grapple facts for kids

Quick facts for kids Grapple
The Grapple 1 test in May 1957. It was called Britain's first hydrogen bomb test, but it didn't work as planned.
Information
Country	United Kingdom
Test site	Kiritimati (Christmas Island), Kiribati; Malden Island, Kiribati
Period	1957–1958
Number of tests	9
Test type	Air drop, balloon
Max. yield	3 megatonnes of TNT (12.6 PJ)
Navigation
Previous test series	Operation Antler
Next test series	NTS series

Operation Grapple was a series of British nuclear weapons tests that happened in 1957 and 1958. These tests involved early atomic bombs and powerful hydrogen bombs. They took place on Malden Island and Kiritimati (also known as Christmas Island) in the Pacific Ocean. These islands are now part of Kiribati.

The goal of Operation Grapple was for Britain to develop its own hydrogen bomb. After nine nuclear explosions, the United Kingdom became the third country to have these powerful weapons. This also helped to improve the special friendship and nuclear sharing between Britain and the United States, leading to the 1958 US–UK Mutual Defence Agreement.

Why Britain Needed the Bomb

A Secret Wartime Project

During World War II, Britain had a secret project called Tube Alloys to build nuclear weapons. In 1943, this project joined forces with the American Manhattan Project. Many top British scientists helped the Americans build the first atomic bombs.

After the War

After the war, Britain worried about losing its place as a powerful country. So, the government started its own atomic bomb project again, called High Explosive Research. In 1952, Britain successfully tested an atomic bomb in Operation Hurricane. This was a huge scientific achievement.

However, the United States had already developed even more powerful thermonuclear weapons, also known as hydrogen bombs. Britain was several years behind. In 1954, the British government decided that to remain a "great power," it also needed to develop hydrogen bombs.

Designing the Bombs

Scientists at the Atomic Weapons Research Establishment in Aldermaston worked on three main designs. These included a large fission weapon called Orange Herald and two types of hydrogen bombs: Green Bamboo and Green Granite. A hydrogen bomb works in two main steps. First, a small atomic bomb (called the "Tom") explodes. This explosion then triggers a much bigger fusion reaction in the second part (called the "Dick").

These new bomb designs had to be tested to make sure they worked. This is why Operation Grapple was planned.

Choosing a Test Site

Finding a Safe Place

Testing nuclear bombs is very dangerous. After a Japanese fishing boat was accidentally exposed to radioactive fallout from an American test, it became clear that a very remote test site was needed. Scientists looked at many islands in the South Pacific and Southern Oceans.

Malden and Christmas Islands

The survey ship HMNZS Lachlan helped survey the islands.

Eventually, Malden Island was chosen for the air-dropped tests. It was an uninhabited island claimed by both Britain and the United States. Kiritimati (Christmas Island) was chosen as the main base for the operation. It was also claimed by both countries and was very far from other places.

Christmas Island was a tropical island with grass and coconut trees. About 260 local people, called Gilbertese, lived there and worked on coconut farms. For their safety, many of them were moved to a nearby island during the tests.

Getting Ready for the Tests

Setting Up the Operation

The secret name for the test series was Operation Grapple. Air Vice Marshal Wilfrid Oulton was put in charge of the whole operation. Many different parts of the British military were involved, including the Royal Air Force (RAF) with its Vickers Valiant bombers and English Electric Canberra planes.

Building the Base

Royal Engineers building huts on Christmas Island.

The Royal Engineers and RAF worked hard to get Christmas Island ready. They improved the airfield so large planes could land and take off. They also made the port better and built new facilities. This included roads, power, water, and storage. The island's population grew to 3,000 people during this time.

HMS Warrior, an aircraft carrier, was the main ship for the tests.

Many ships were used to bring supplies and people. HMS Warrior, a light aircraft carrier, was the main control ship. HMS Messina, a large landing ship, became the headquarters ship.

The United States military also gave a lot of help. RAF planes could fly over the US, and ground crews stayed at US air bases. This cooperation was very important for the operation.

The Tests Begin

First Series: Grapple 1, 2, and 3

The first series of tests had three explosions. All the bombs were dropped from planes over Malden Island. They were set to explode high in the air to reduce nuclear fallout, which is dangerous radioactive dust.

A Vickers Valiant B1 XD818 bomber, like the one used in the tests.

• Grapple 1 (May 1957): The first bomb, called Short Granite, was dropped. Its explosion was much smaller than planned, about 300 kilotonnes of TNT (1,300 TJ). Even though it didn't work perfectly, the government said it was a successful hydrogen bomb test.
• Grapple 2 (May 1957): This test used Orange Herald. It was a very large fission bomb, not a true hydrogen bomb. Its yield was about 720 to 800 kilotonnes of TNT (3,000 to 3,300 TJ), making it the biggest single-stage nuclear device ever exploded. Britain kept this secret for many years.
• Grapple 3 (June 1957): This test was another try with a fixed Short Granite bomb, called Purple Granite. Its yield was only 200 kilotonnes of TNT (840 TJ), which was very disappointing. Scientists knew they had to try again.

Grapple X: The First True H-Bomb

The destroyer HMS Cossack helped keep ships out of the test area.

A second test, called Grapple X, happened in November 1957. To save money, this bomb was dropped near Christmas Island, only 20 nautical miles (37 km; 23 mi) from the airfield. This meant building new shelters and facilities on Christmas Island.

The bomb, called Round A, was dropped by a Valiant bomber. Its explosion was about 1.8 megatonnes of TNT (7.5 PJ), which was even bigger than expected! This was the first real hydrogen bomb that Britain had successfully tested. The large explosion caused some damage to buildings and helicopters on the island.

Grapple Y: The Biggest Test

The Grapple Y test on 28 April 1958.

Scientists at Aldermaston kept working to improve their designs. They came up with a new bomb called "Dickens." The test for this bomb, called Grapple Y, happened in April 1958.

This bomb had an explosive yield of about 3 megatonnes of TNT (13 PJ). It remains the largest British nuclear weapon ever tested. This test was very successful because most of its power came from the fusion reaction, making it a true hydrogen bomb. Also, its yield was very close to what the designers predicted, showing they understood how to build it.

Grapple Z: Final Tests

An Avro Shackleton aircraft helped patrol the test exclusion zone.

In August 1958, the US President announced a one-year break from nuclear testing, starting in October. This made Britain and the Soviet Union rush to do as many tests as possible before the deadline.

The final series, Grapple Z, had four tests. These tests explored new ways to make bombs smaller and lighter. They also looked at how to make bombs immune to damage from other nearby nuclear explosions.

The East Point balloon anchor on Christmas Island. Some bombs were lifted by balloons for testing.

• Pendant (August 1958): This bomb was lifted into the air by four large balloons instead of being dropped from a plane. It had a yield of about 24 kilotonnes of TNT (100 TJ).
• Flagpole (September 1958): This bomb was dropped by a Valiant bomber using radar, not by sight. It exploded with a yield of about 1.2 megatonnes of TNT (5.0 PJ).
• Halliard (September 1958): This was an unusual three-stage bomb design. It was also dropped by a Valiant and had a yield of about 800 kilotonnes of TNT (3,300 TJ).
• Burgee (September 1958): The final test was another balloon-borne bomb. It had a yield of about 25 kilotonnes of TNT (100 TJ).

These tests helped British scientists learn everything they needed to build powerful, modern hydrogen bombs. The international break in testing began on October 31, 1958, and Britain never tested nuclear weapons in the atmosphere again.

Summary of Tests

What Happened Next

Working with the United States

US President Dwight D. Eisenhower and British Prime Minister Harold Macmillan meeting in 1957.

After the Soviet Union launched the first satellite, Sputnik 1, in October 1957, the United States was shocked. This made them more willing to work with Britain again. British Prime Minister Harold Macmillan suggested that the two countries share their knowledge.

Because Britain had successfully developed its own hydrogen bomb, the US government changed its laws. This allowed them to share nuclear technology with Britain again. In 1958, they signed the 1958 US–UK Mutual Defence Agreement. Macmillan called this "the Great Prize."

This special relationship helped Britain a lot. Britain started using American bomb designs, like the Mark 28, which became known as Red Snow. Britain also received nuclear materials from the US. Later, the British Navy even used American missiles with British nuclear warheads.

Other Tests and Independence

The United States also used Christmas Island for its own nuclear tests in 1962, called Operation Dominic. Twenty-four nuclear bombs were exploded near the island during this time.

In 1979, the islands, including Christmas Island and Malden Island, became the independent country of Kiribati. The spelling of Christmas Island's name was changed to Kiritimati, which is how it's written in the local Gilbertese language.

Health Concerns

Over the years, there have been concerns about the health effects on the servicemen who were part of Operation Grapple. Some studies have looked at the health of these veterans. One study found that some veterans had a higher rate of certain changes in their blood cells.

The UK Ministry of Defence has stated that few people were exposed to much radiation. They also say that studies have shown little or no health effects. However, some veterans believe that their illnesses, and even health problems in their children, are a result of being exposed to radiation during the tests.

Many veterans have tried to sue the Ministry of Defence for damages. In 2012, the Supreme Court did not allow a group of British ex-servicemen to sue. However, in 2015, the Prime Minister of Fiji announced that the Fijian government would give compensation to the Fijian servicemen who took part in Operation Grapple. In 2022, British nuclear test veterans were awarded a medal after many years of campaigning.

Images for kids

• 

  Grapple 1 test in May 1957. Hailed as Britain's first hydrogen bomb test, it was in fact a failure.

• 

  Royal Engineers assemble huts on Christmas Island

• 

  HMS Warrior, a Colossus-class light aircraft carrier, was the headquarters ship for Britain's atom hydrogen tests on Christmas Island.

• 

  View from an RAF Handley Page Hastings transport flying over Christmas Island in August 1956.

• 

  HMS Messina, the headquarters and communications ship for Operation Grapple

• 

  Royal Engineers construct the airfield runway.

• 

  The destroyer HMS Cossack

• 

  An Avro Shackleton

• 

  The East Point balloon anchor on Christmas Island. The bombs for Grapple Z1 and Z4 were hoisted by balloons from here.