The RNZN and Operation Grapple

When HMNZ Ships PUKAKI and ROTOITI, two of our Loch-class frigates, departed Auckland for Christmas Island at 0900 Thursday, 14 March, 1957 they became an essential part of Operation Grapple, Britain’s hydrogen bomb tests in the Pacific. Britain’s determination to retain its status as a great power in a Cold War context, demanded the development of nuclear weapons to deter the USSR and to have parity with the USA. After successfully developing an A bomb, the British resolved to build a Hydrogen bomb as the primary weapon of their deterrent jet V-bombers. Their search for an isolated test site led to the Pacific and Captain James Cook’s Christmas Island. Britain asked the New Zealand government to provide two RNZN frigates as weather ships to provide meteorological reporting for the British testing programme.
All of the four deployments by our two frigates during Operation Grapple were similar. Departing Devonport, Auckland they all had stops in transit at Fiji, Western Samoa or the Cook Islands, and often they dropped off stores or mail at Raoul Island.
As they closed on the equator and crossed it towards Christmas Island the lack of air-conditioning on the frigates made the increasing heat and humidity an escalating problem for all in the ships. The tedium of shipboard life at sea was relieved in the manner that only sailors know, with the combined effect of maintaining both morale and efficiency.
But in addition the internal preparations, drills and exercises relating to shutting down the ship when passing through a zone of radioactive fall-out were practised regularly. Action stations and damage control states were exercised frequently, usually followed by “shelter stations” which simulated the ship being covered in nuclear radiation. With the exception of the essential crew needed to maintain the ship’s cruising state, everyone went below the water-line – to avoid horizontal radiation – while the external air supply was closed down, re-circulating the air between decks in the ‘citadel’ and squeezing everyone into the confined areas of the lowest mess decks, storerooms and even in magazines.
The crew regularly exercised the routine to be followed when inside the Test Area with a nuclear explosion imminent. The upper deck hoses were used to pre-wet the decks as the ship went to the highest damage control state. The ship’s company was mustered on the upper deck with only the engine and boiler rooms running.
Everyone was dressed in their AWDs with their anti-flash balaclavas and gloves. Trousers were tucked into socks, cuffs of sleeves into gloves and sun-glasses donned to protect any exposed skin and eyes from flash. When the warning order came from the bridge they all sat down with backs to the rail or a bulkhead with their backs to the site of the explosion. They placed their hands over their eyes as the countdown began. At the conclusion of the weapon test the ship was covered in a shower of spray to wash away any radiation before monitoring teams in AWDs, face masks and breathing gear searched for radiation hot-spots. The drills became very serious business as the ships entered the Grapple Restricted Area around Christmas Island.
On arrival at Christmas Island the frigates joined the Royal Navy flotilla in the anchorage at London Roads. The ship went on to tropical routine and all faced the monotony of watch-keeping with the problem of filling in the spare hours at anchor. Officers and sailors hosted social occasions in their respective messes which established an easy rapport with the ships of the Royal Navy. The Task Force Commander regularly addressed each ship’s company prior to each Bomb Test while Royal Navy staff officers were frequent visitors to the frigates. Afternoon shore leave was granted for swimming parties, and canteen leave ashore granted to give sailors a break from the ship. The only place to visit was the wet canteen in Port London, a steel Nissan hut with steel tables and chairs and English beer served in tins, but it became a popular meeting place for sailors, soldiers and airmen from the UK and New Zealand.
The coral on Christmas Island was a major handicap for sporting contests as it caused nasty wounds which were slow to heal. On-board entertainment was primarily British films –the Grapple task force was well supplied with movies from the UK. But a considerable amount of time was spent perfecting the prime function of the RNZN frigates for the operation – weather reconnaissance and reporting.
The weather ships were supplemented by RAF Canberra bombers, which made high and low level flights to produce additional weather observations. Ideal Test requirements demanded weather conditions that ensured the mushroom cloud would disperse over the nearly 5,000 miles of empty sea, away from any Pacific Islands or Japan. So the ship’s task was essentially wind-tracking, which was carried out by launching hydrogen-filled meteorological balloons to a height of 60,000 feet which were tracked by the frigate’s height-finding Type 277 radar.
Weather balloon runs were carried out prior to each Bomb Test, when a balloon was launched every six hours from the balloon hut built aft on the upper deck of the frigates. The balloon ascended 6,000 feet (1.8km) every six minutes at which point it recorded wind direction and speed, air temperatures and barometric pressure which were transmitted to the Weather Centre on Christmas Island. Tracking terminated after an hour or so, when the balloon exploded at about 70,000 feet (21 km). It was an important function and demanded considerable expertise of the radar plotters responsible. At least one balloon was tracked to 119,000 feet!
The actual nuclear bomb tests occasioned considerable tension and excitement throughout the ships. As the vapour trail of the Vickers Valiant carrying the bomb loomed over the horizon the ship went into countdown to the explosion. The aircraft reported the bomb release. The flash was intense and many sailors recall that for a moment the bones of their fingers were visible through closed eyes. Then came the heat, like a warm breeze on everyone’s back. With the explosion, a ‘count up’ began, until the command came from the bridge to stand up and turn around. Typically there was an awed silence among the ship’s company, as they watched the gigantic fireball glowing intensely and growing larger as it rose into the sky – then the double crack of the explosion which came racing across the water with a dull thud. As the cloud rose it transformed into the characteristic white mushroom cloud, expanding until the upper atmospheric winds flattened off the top.
The Royal New Zealand Navy’s contribution to Operation Grapple came to an end when PUKAKI sailed into Devonport on Thursday, 9 October 1958. While the sailors willingly did their duty, we know now that few of the New Zealand sailors who were at the bomb tests have emerged unscathed from their experience.

Op Grapple – the bomb tests
Test Date Type Yield RNZN Ships
Grapple 1 15 May 57 Air dropped bomb 300KT* PUKAKI & ROTOITI
Grapple 2 31 May 57 Air dropped bomb 700KT** PUKAKI & ROTOITI
Grapple 3 19 Jun 57 Air dropped bomb 200KT PUKAKI & ROTOITI
Grapple X-ray 08 Nov 57 Air dropped bomb 1.8MT*** PUKAKI & ROTOITI
Grapple Yankee 28 Apr 58 Air dropped bomb 3.0MT PUKAKI
Grapple Zulu 1 22 Aug 58 Suspended from balloon 24KT PUKAKI
Grapple Zulu 2 02 Sep 58 Air dropped bomb 1.2MT PUKAKI
Grapple Zulu 3 11 Sep 58 Air dropped bomb 800KT PUKAKI
Grapple Zulu 4 23 Sep 58 Suspended from balloon 25KT PUKAKI
Notes:KT = kilotons; thousands of tons of TNT equivalent
MT = megatons; millions of tons of TNT equivalent
* Grapple 1 was a failure, no fusion reaction occurred, only a fission explosion.
** Grapple 2 was a fission weapon (A-bomb) Britain’s largest ever.
*** Grapple X-ray was Britain’s first successful H-bomb.
Subsequent tests proved variations of weapon design

11 thoughts on “The RNZN and Operation Grapple

  • My Brother Boyd Wilcox was one of those crewmen who was standing on the front of the ship while the first H Bomb had exploded.. He was on the Frigate Pukaki and was involved with the first atomic bomb.

    Reply
  • Merehora Taurua

    Arohamai Charlotte. Ngapuhi will be giving evidence against the crown in its treatment of our grandfathers, fathers, brothers, uncles, cousins and nephews used in their plotted warfares and experiments thereto. I had cousins in the thick of the Mururoa Atoll testing. None of them are alive and were my age.

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  • D Watson

    LT Douglas Bamfield was the Navigator of HMNZS Rotoiti at the time of the tests. He was on the upper bridge at the time of the tests measuring the speed of the ascent of the cloud at the time of the explosion. Apparently all of the crew had protective gear on at the time except himself. Apparently the reason he had no protective clothing on was because he was handling instruments such as sextant and chronometer to complete his tasks. Apparently about six months later all exposed crew were medically assessed and some were found to have radiation effects. Although the vessel was approximately 200 nautical miles from the test site immediately after the cloud had dissipated the vessel steamed directly towards ground zero. He remembers the that he went ashore later at Christmas Island. Now at nearly 93 years of age he has clear recollections of this event and is in good health.

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    • Nina

      Yes and he is still going strong.His memory is fading but we’ve chatted quite a lot about this event.He can’t recall a D Watson but contact me if you wish him to know more about you. I am caring for him at the moment while his wife is away.Nina

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  • My poppa was involved in this! I wish he was still around to tell me about it – I was too young to care back then. He was involved later in trying get get compensation for all these sailors due to the exposure and the fact most were riddled with cancer. Unfortunately, he was not successful and died of cancer in 2001.

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  • vincent wright

    My Father Noel Stephen Wright was on board the Pukaki (in the engine room).
    My youngest sister died of a heart defect when she was 16 months old.
    My younger sister now has ovarian cancer which is now untreatable and has been referred to palliative care..
    Me myself are ok to date.
    I would not wish anyone to be exposed to nuclear radiation or Fallout and try to live a healthy life, ,have children etc..
    Thanks for the efforts of Roy Sefton for his efforts to raise awareness for the sailors and their families which have been affected.
    Vincent 2017

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  • Alan Kerr

    What stage are we with claims against the British government? Has any progress been made? My father who was on the Rotoiti died of cancer and now 2 of my 3 daughters and I have unusual health problems. My sister also had a huge battle will cancer. We don’t know if there is a connection as yet as we don’t have enough info.
    Alan
    2017

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  • ken mccann

    My father was onboard the Pukaki during these tests and died of Alzheimers. I believe Roy Sefton was the lead on hiring a British law firm to commit to recompense for all those on board at the time. So far – nothing!!

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  • Alan Kerr

    I think the full truth hasn’t come out about this. My father told me of his time on the Rotoiti through these tests but there are no pay records or any other record. From what I can gather he was involved in the revolt, mutiny, protests or whatever label you want to paint it within Auckland over pay and conditions. My understanding is many were dismissed from official service but a deal was done where some of them returned but probably not as registered servicemen I presume. This could explain lack of records where his pay records show very little time on the Rotoiti where in fact he told me it is where he served the longest. He showed me photos of what they wore, he was a pompom gunner and from my childhood memory, they had similarities. He told me they anchored 25 miles from ground zero with backs to the detonation and hands over closed eyes and still saw the bones in his hands. He left the navy after the tests then I was born end of 58. He did two tours of Korea but records don’t show this, told me about how they landed NZ navies first group of commando type squad that the captain had organised after spending time with Americans. He spent time in Japan during this period and he had photos of him at famous Japanese landmarks and brought back many Japanese souvenirs. He must have spent a good amount of time with the Americans because as a child we visited in Lyttleton both a US Coastguard icebreaker who he was friends with the captain and onto a US submarine where again he was friends with the captain or first who took us out on the harbour. I remember them talking about the Korean War. Another time I remember was I presume it was a frigate anchored off the heads of Okains Bay where every Christmas the same group of league boys who also served through Korea holidayed with our families. I always presumed but don’t know for sure they were exposed during grapple also. They must have known the skipper very well on the navy ship anchored off the bay and arranged this earlier in Christchurch. The frigate sent a boat into the bay to pick up Ray Philpot, Ivan Pimley my father Dave Kerr and a couple of others whose names escape me at the moment. I think another league boy Hapi October was also shipmates with them. Someones hiding something when I am told my memories aren’t real, my father was dismissed after the Auckland strike and I imagine his shipmates who struck records are also missing. What is the agenda here? Is the navy trying to hide to identities of as many as they can? Something isn’t right. All but Hapi died of nasty cancers, coincidence or not? We won’t know but it is time the navy showed these servicemen some respect and tell the families the truth.

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    • Alan Kerr

      I would have edited this but can’t see how so will add this footnote:
      after detonation, the frigate would then sail into ground zero to run some tests. I am thinking they were the rats being tested. Also, why does the NZ Navy not support these servicemen for compensation? Other nations paid their guinea pigs compensation. The navy should be ashamed of itself not supporting these victims.

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      • m b roche

        Usually it is a govt (cabinet) decision to send troops anywhere. The meetings between senior armed forces (in this case navy) and govt ministers would be sealed and top secret. – no records.
        Govt does not wish to admit anything , armed forces require funding from govt so will deny, deny, deny.
        NZ govt have always been willing puppets of USA and UK.

        Reply

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