Fred Towler was keen to go. He was 23 and his ship had government orders to steam 4300km from Auckland to patrol off Mururoa Atoll in French Polynesia.
"I was navy to do things for New Zealand, no matter what. I had agreed with nuclear weapons because then - in 1973 - we were under the American and British defence umbrella. But we knew this was not firing nuclear weapons - but a protest," recalls Mr Fowler, now 64.
Waiting weeks for the French to detonate a nuclear warhead, the ship's company, off duty, amused themselves with a Miss Otago contest, games of poker and bingo and a naval version of snakes and ladders called "uckers".
French military planes flying overhead were greeted by the sailors on deck with "brown eyes".
Their ship was to see one test on its assignment.
"When the test was about to happen we were below at battle stations with doors and hatches tightly closed. We knew where we were and were told it was a safe zone - and sat there while the bomb went off.
"We waited 10-15 minutes and then the captain broadcast we could look. We raced up top and could see the cloud slowly coming up the horizon."
Forty years on, Mr Towler is unsure whether he and his mates were exposed to radiation.
"You expected your boss to know you were going into atmosphere that was safe and you'd be fine."
But the belief of many Mururoa veterans that they were using desalinated sea water contaminated by nuclear fallout appalls Mr Towler.
"We showered in it twice a day."
That there could be a sinister side to a peaceful gesture by his Government did not dawn on him until well after he left the navy in late 1986.
Two of his three children, born some years after he came ashore, needed operations for a deformed gullet - the tube to the stomach.
His eldest son had slight cerebral palsy.
The medical specialist treating the gullet problem told him his was the only family in New Zealand to have that happen twice.
Also disturbing was the number of naval friends dying of cancer. "I can count on two hands the people who had cancer."
He had considered the possibility that "science got it completely wrong" when it came to assurances to the ships' officers that their crews would not be exposed to fallout risk and later, that they were not exposed.
"It is time that the Government looked into deformities of the children related to the crews on HMNZS Otago and HMNZS Canterbury," he said. "Some type of financial benefit to assist them in their life as disabled. At least, the Government should cover their medical costs."