When Robert Bates and the other crewmen on the USS Navarro were ordered to Hawaii in 1963 it seemed like a vacation.
"It was basically an R&R cruise," says Bates.
There was rest, relaxation and a mystery.
"There were people with chemical suits on the ship with some kind of apparatus apparently monitoring what was going on," explained Bates.
"They wouldn't talk to you," he added. "You'd try to carry on a conversation, try to find out what was going on, they just flat ignored you. It always bothered me."
The Hawaii mission was code-named Autumn Gold. A similar operation off Newfoundland was called Copper Head.
According to a Pentagon briefing film obtained by CBS News, the goal was to test the vulnerability of Navy ships to germ warfare attack.
Nine times within a month jets sprayed clouds of a biological weapons simulant in front of the ships.
According to the film, "A biological tracer, BG, was disseminated by a 4-C jet aircraft."
BG, a bacteria considered harmless by the military, is used to simulate the deadly anthrax germ.
The briefing film explains, "Immediately following the BG release another plane flying the identical flight path released fluorescent particles."
"I remember an airplane flying over and I could see it sprayed something and then a little later I felt this mist on my face," says George Arnold who was on the deck of the Navarro during Autumn Gold.
Arnold wonders why didn't the military spray empty ships? Why were men on board? He thinks he has the answer.
"They were doing that just to see how much they could get stuff absorbed into our body, probably in the amount it would take to kill us if they were to use something like anthrax," says Arnold.
Most of the test reports remain classified but in documents obtained by CBS News, sailors on the "target ships" are called "test subjects." Only eight men wore gas masks. They were the "control group" in this experiment. Other crewmen including Arnold were ordered to give throat swabs or gargle samples.
"They would call back from the bridge and tell us to take out a specific bottle and use it as a mouthwash or a gargle then spit it back into the jar and seal it up," says Arnold.
In a written statement the Pentagon tells CBS News the sailors "were not exposed to any harmful chemical and biological compound" and they all "were fully informed about the details of each test." That's news to the dozens of sailors we spoke with.
"We weren't given any information, we didn't know anything," says Bates.
If, as these men tell CBS News, they were not informed and never gave their consent, then it doesn't matter that the military thought the materials were harmless. The tests violated government policies in place for the last 50 years which state: "The voluntary consent of the human subject is absolutely essential."
"I don't think when a person joins the armed forces they're giving their body up for science. I don't think that's suppose to be done. I'm very, very mad about them doing this. Its not right," says Bates.
"I think you're in there to serve your country do what needs to be done to protect it, and I don't think being used as a guinea pig..." says Arnold, "is one of those jobs."
Thirty-five years later much about the tests remains classified. More is known about the substances used.