To add to the sense of urgency, public opinion across the world was hardening against the testing of H-bombs. But Penney was used to pressure and he put all his energies into the project. His small, but dedicated team responded in kind and gradually designs for their super-bomb began to roll off the drawing board. Their most pressing task was to test the new weapon before a proposed ban on atmospheric nuclear testing came into force.
But after a year, the prospect of failure still loomed large and in desperation the Conservative Government led by PM Anthony Eden visited Aldermaston in September 1956 and agreed a top secret plan with the atomic weapon scientists to fool the world into thinking Britain had a thermonuclear capability.
Given the problems of making an H-bomb and the pressure of time, they had to make sure that if the ‘super’ failed there was an alternative fail-safe method of ensuring a big bang at the forthcomings tests. Britain could not afford to lose face. They decided to build a massively enlarged version of the existing A-bomb, which the scientists were much more confident about, and pretend it was an H-bomb. This wouldn’t fool the Americans of course; cloud sampling aircraft would soon spot the ruse. But it would fool most of the international community and buy time for the scientists to sort out any production delays or design faults in the real H-bomb.
Penney and his team had come up with three designs, two were experimental hydrogen bombs which they knew could easily fizzle out; the third was the massive atomic device, which they were confident would give the big bang necessary to convince the world. This ‘political bomb’ enabled the Government to confidently announce that tests of Britain’s hydrogen bombs would take place in the central Pacific Ocean in early 1957.
After much debate, a small uninhabited atoll called Malden Island was chosen as the site to test Britain’s H-bomb. Logistics and support troops would be based on Christmas Island, 400 miles to the north; it was infrequently inhabited by about 100 natives from nearby islands who harvested copra. A disused airfield, last used by the Americans in World War 2, had to be completely rebuilt and a site prepared for at least 3,000 troops and RAF personnel. The aircraft carrier HMS Warrior would be the command ship for the naval fleet. Hawaii, 1,200 miles away, was the nearest civilisation.
The codename ‘Grapple’ was chosen for the forthcoming trials, its four prongs a symbol of cooperation between the three armed services and the Aldermaston bomb makers.
Preparations began at once. Army sappers from 35 Field Squadron, the Royal Engineers, on their way home from a year’s posting in South Korea were suddenly diverted; the only information they were given was that their destination was “somewhere in the Pacific.” The troops, kitted out in cold weather clothing in preparation for Britain’s more temperate climate, found they were sweltering in 100 degrees heat as they clambered ashore at Christmas Island.
It was weeks before the supply ships arrived with tropical gear and the equipment they needed to get on with the task in hand. Meanwhile many men ‘went native’, walking about half naked and spending their days fishing and swimming in the warm waters. There were shortages of certain foodstuffs such as bread and milk, but their diet was supplemented by the plentiful supply of fish and coconut milk. One thing they were not short of was beer: a huge amount had been off-loaded from their troop ship in preparation for the setting up of a NAAFI. The men naturally made good use of this unexpected largesse, and often went swimming in the lagoons afterwards, with inevitable consequences. Although the waters looked calm enough, they were deceptive and the reefs just offshore hid a treacherous drop-off point into very deep water. Several men lost their lives as they were sucked into the abyss, or by being attacked by sharks.
Finally the supply ships arrived and order was restored; the men were soon hard at work building the base camp for the imminent arrival of thousands of troops from Britain. In a few months, a 7,000-foot runway for the Valiant aircraft that would drop the bomb was built; 25 miles of tarmac roads followed, and special buildings for the bomb assembly were erected. With little natural fresh water, a sea water distillation plant was also installed.
By May 1957, the scientists were ready for their first test, but international opposition was growing. The Japanese, who had more reason than most to oppose the bombs, threatened to stop the test by sending a ‘suicide fleet’ to the danger zone.
To avoid embarrassment, the Air Ministry entered into an elaborate subterfuge with a journalist from the Daily Express who agreed to fake a story implying that the tests had been delayed and that William Penney was flying to Australia on a special mission. The flight plans as well as the code name, ‘Mr Elmhurst’, that Penney habitually used to avoid unwanted publicity, were also leaked to convey the impression the scientist was planning more bomb tests in Australia. A body double was used to impersonate Penney at several high-profile gatherings. Whether the Japanese were fooled is not known, but there were no ‘suicide protesters.’
The task force ships, led by HMS Warrior, moved into position a few miles off Malden Island and the British Government announced that a vast area of ocean covering 750,000 square miles was a no-go zone. It was a clear signal to the world that the bomb tests were imminent. The passage of several Valiant bombers, resplendent in bright white livery to deflect heat, through Hickam U.S. air force base in Hawaii was another certain indication.
With the eyes of the world now on a tiny dot in the middle of the Pacific Ocean, the government was most anxious to avoid looking foolish. But Penney under enormous pressure was forced to admit that he still couldn’t know for sure whether their bomb would work, and to avoid any embarrassment, it was decided that no newspapers would be invited to witness the first test.
The device chosen was a two-stage (Tom and Harry) prototype H-bomb, designed to produce a thermonuclear yield as close as possible to a million tons of TNT, one megaton. The components were manufactured at Aldermaston and then taken by convoy to RAF Wittering in Lincolnshire, prior to being flown to Christmas Island for final assembly.
But things went far from smoothly; there were annoying problems from the start. The aircraft carrying the ‘ball’ of radioactive material for the bomb, enclosed in a 700 pound lead container, for some reason lost radio contact on route to Hickam airport where it was to be collected for the final leg of its journey to Christmas Island. Inexplicably there had been problems with communications all the way from Canada and the crew were unable to contact the Americans who, after giving special permission for the Hastings aircraft and its ‘special’ cargo to fly over its territory, insisted in being informed of progress every step of the way.
This led to fears the aircraft was lost, and the ensuing panic saw the entire US air force being put on ‘red alert.’ And although contact was eventually made, the USAF was taking no chances. When the Hastings finally landed at Hickam with its top secret cargo, it was met by a flotilla of fire engines and military vehicles that accompanied the plane, bells clanging madly right into the hangar.
With secrecy blown out of the window, the operation had to continue in the full glare of publicity from local radio stations and newspapers who broadcast sensational stories about the “doomsday flight.” Plans were quickly re-drawn and the operation’s scientific director, William (Bill) Cook, had to be smuggled humiliatingly into Christmas Island like a sack of potatoes on the weekly supply flight.