10 Seconds That Shook the World
Cathcart, Brian, The Independent (London, England)
THE MONTE BELLO Islands lie off the north-west coast of Australia. About the size of the Scilly Isles, they are in fact desert islands, the last afterthought of the great arid wastes that dip beneath the sea 80 miles away. Over the years they had seen the occasional shipwreck, turtle hunters and pearl divers had stopped off there, but no one had ever really settled. In 1952, however, their peace was broken by the arrival of a party of military engineers. Roads, jetties and camps suddenly appeared, cables were laid and odd buildings sprang up. In August an aircraft carrier HMS Campania delivered about 100 British scientists - from Fort Halstead in Kent, Woolwich Arsenal in London, Shoeburyness in Essex and Aldermaston in Berkshire, all military research establishments. Along with them came a frigate, HMS Plym, which was anchored securely in a lagoon at the centre of the islands. Inside the Plym was an atomic bomb.
The second half of September was taken up by painstaking rehearsal of the elaborate procedures of a nuclear weapon test: the priming of equipment, evacuation of personnel and the countdown itself. On Wednesday 1 October, unfavourable winds forced a day's delay, but by the next morning the forecast was improving.
At 6.30am Leonard Tyte, the technical director for the test, and Rear Admiral David Torlesse, the naval commander, decided to gamble on the weather. The signal "Tare Dog" went out to the task force, meaning: "Today is D-1 Day" and with this began Phase Mercury, the first stage of the countdown, which involved the final preparation of scientific apparatus and the evacuation of personnel. The centre of communications was divided between the flagship Campania, where Torlesse, Tyte and William Penney, the director of Britain's atomic bomb project, were in charge, and the control centre on the islands, H1, where two senior scientists, Charles Adams and Ieuan Maddock, were monitoring the build-up. After another favourable weather forecast, four of the five ships of the task force - all except the Plym - began their withdrawal from the islands leaving 60 men behind.
At H1, strung along a bluff near the south tip of the islands, a fretful night was beginning. This would be the only land site occupied when the bomb went off; the nearest manned point to ground zero. "It was cold and windy in the camp that evening and conditions superficially did not seem to be suitable for the trial," wrote John McEnhill, a scientist who acted as the operation's historian. "A sense of tenseness was evident in the mood of the company. However the repeated rehearsal of final activities was now paying dividends and there was no sign of panic or last-minute chaos."
Late in the evening there was a short lecture in the mess hut to explain to anybody in need of reassurance what they were likely to experience. A bank of knowledge had already been built up from Hiroshima and Nagasaki and from American test explosions. H1 was nearly seven miles from the Plym, a range considered safe from radioactive contamination provided there was no dramatic change in the wind direction immediately after the blast. And those at the site would be evacuated on to the task- force ships after the bomb went off.
That was assuming it did. Any minor hitch could cause a postponement and, given the vagaries of the weather, this could mean no other opportunity for a test that year. There was also the chance that it might not work at all. The British bomb was the closest possible imitation of the American plutonium bomb dropped on Nagasaki, but the United States, jealous of its atomic monopoly, had refused to help, and inevitably the design had diverged in various ways from the original. As a result, what lay in the hold of the Plym was an unproven design and no one was certain that the components were up to standard. All they could do was go through the prescribed motions and hope. …