Alan Rimmer - Between Heaven and Hell

This, after all, was Britain’s ever biggest bomb. If ever there was a case where the dog should have been barking loudly and urgently, this was it. But the government of the day treated it as a matter of little importance. In fact the silence was deafening.

The press, was also uncharacteristically subdued. Instead of trumpeting it to the heavens, the following anodyne article that appeared in the Times (The government’s traditional mouthpiece) on April 30, 1958 was typical of the way the incident was reported at the time:-

A British nuclear device was successfully exploded at a high altitude over the central Pacific yesterday. It was announced last night that Mr Aubrey Jones, the Minister of Supply, had received a report from Air Vice-Marshal Grandy, task force commander, Christmas Island. It was stated scientific measurements were being collected for accurate evaluation, and that early indications were that fall-out would be negligible.

Considering that Grapple Y was the culmination of Britain’s H-bomb tests which the year before had been afforded banner headlines and spread across acres of newsprint as a “dress rehearsal for the death of the world”, this was a remarkably muted response.

The official record of the event was also notable for a complete lack of drama. Group Captain William Edmund Townsend of the Royal Australian Air Force, one of several official observers specially flown to Christmas Island for the Grapple Y test, reported:-

After breakfast, we were taken to witness the shot. It was learned this was a “clean” hydrogen bomb. The air burst precluded any water or dust being drawn up from the surface which may give possible radioactive fall-out and it was not anticipated that any fall-out from this bomb would occur.

He makes his glimpse of Armageddon sound like a stroll in the park. It is interesting to note, however, that Townsend reports he “learned” that it was a clean bomb; in other words he was acting on information received rather than what he observed.

There is no mention anywhere of the storm clouds that gathered after the burst, much less about any ensuing rain. Like the dog in the night-time, Townsend, a dyed-in-the-wool establishment figure later awarded the CBE, was curiously silent on that score.

In the absence of an inquisitive Sherlock Holmes, Grapple Y faded unheralded into history; an event of little consequence.

It was 50 years before it was brought blinking back into the daylight when John Large, a consultant nuclear engineer internationally respected for his work in assessing the risks posed by nuclear explosions, identified Grapple Y as a possible cause of contamination on Christmas Island.

His interest was aroused after one of the few photographs of the bomb was published in a scientific journal. It was a classic picture of a nuclear explosion complete with majestic mushroom cloud. But what made it unusual was the stem of the cloud which was oddly striated with a series of tooth-like ridges round the edges.

Large was convinced this was caused by the explosion sucking up large amounts of sand and sea water into the stem. This, of course, was contrary to the accepted wisdom that the bomb was exploded too high in the air to cause fallout. Large made a study of all the available photographs of Grapple Y together with rare video footage and reached the conclusion that the bomb exploded much lower than had been admitted by the Ministry of Defence.

He calculated, from a series of “timed, sequential photographs of Grapple Y” that the detonation height was 1,500 metres, and not the official height of 2353 metres. Large suggested that the troops could have been contaminated by the resulting fallout.

It was a convincing argument that was given a cameo role in the various court hearings. Unfortunately its importance was overshadowed by the Rowland Report which usually received star billing.

It was only after the debacle of the Supreme Court hearing that Grapple Y was re-examined as part of a general review of all the evidence to see what could be salvaged from the wreckage.

The review was undertaken on an ad hoc basis by Ken McGinley and a small group of researchers from the Open University who were looking for evidence which might be useful to nuclear veterans fighting for pensions through the notoriously slow Pensions Tribunals system.

The Australian tests, the so-called “dirty bombs” that had grabbed all the headlines in the 1980s, were once again examined, but there was little fresh evidence about these tests: it had all been said before, so it was decided to put the Christmas Island tests, of which little was known, under the microscope.

These tests had made only sporadic appearances in the headlines, and Grapple Y had made the least impression of all. Even in Lorna Arnold’s seminal work on the hydrogen bomb tests Britain and the H-Bomb published in 2001, Grapple Y is given the least billing. But she did make one very interesting observation: buried away in her account of the bomb is a passage about the task force commander Air Vice Marshal Grandy reporting to his political masters in Whitehall:-

Immediately after the shot the weather had deteriorated and had there been any further delay the operation could not have taken place during the rest of that week. As it was, cloud conditions reduced the number and quality of the photographs obtained.

She doesn’t say precisely what the “deteriorating weather” was but, Penney’s deputy, Bill Cook, reveals another strong clue in an interview he gave to the Bulletin of Atomic Scientists published not long after he returned from Christmas Island. The magazine’s correspondent notes:-

When the test took place Cook showed no sign of excitement. On one crucial occasion when the weather was highly doubtful he carried on seemingly unworried… when it was over, his characteristic smile broke, but only later did he admit that he had been concerned.

Does the weather being “highly doubtful” mean that it rained? And if it didn’t why had he been “concerned?” But these clues were slim pickings and too obscure for the nuclear veterans to make anything of.

Much more was needed. It was decided to probe deeper, and further signs of “suspicious behaviour” by Grapple Y were soon forthcoming.

A trawl of Hansard , the official parliamentary record, revealed that Grapple Y had been the subject of a fierce debate back in 1991. This followed allegations that something had gone wrong with the April 28, 1958 explosion, and that troops had apparently been caught in a deluge of heavy rain.

This had been denied by the Ministry of Defence, but Sapper Arthur Thomas told in an interview for a TV programme: “Suddenly over the loud-speaker system came the order to get under cover quickly and to clear the open ground. Apparently the wind had changed and the fallout cloud was heading back to Christmas Island. I dashed to my motor vehicle and sat in the cab compartment, closed the doors and windows and remained there for half an hour. Shortly afterwards, however, the wind direction reversed and the men were ordered back to their positions.”

Another soldier’s account of what happened is even more dramatic. Tom Birch told the Dispatches programme: “The explosion and the enormity of the cloud left me speechless. I thought, my God what the hell’s going on? We were all quite amazed, you were frightened; all sorts of emotions came out.

“As I walked back to the Port Camp I suddenly became aware of a very thick black cloud approaching inland from the sea. It was as black as pitch. The cloud came over part of the island then retreated back out to sea again. By that time we had all been showered in rain which was as big as ten-pence pieces.

“We all ran like mad to get away from the rain. Lots of men were caught out in the open though. Immediately after the detonation there was panic among the boffins. From the way they were acting it was clear that something had gone far wrong. The whole thing appeared abnormal, unusual.”