I have been through a lot of training over the years. After a few beers, people sometimes ask about the toughest training I have ever seen. After you read this story, I think you will agree that the Combat Diver Qualification Course (CDQC) at the Special Forces Underwater Operations School in Key West, Florida, takes the prize.

I went through CDQC before it was a seven-week marathon — my hat is off to those guys who took the course after I did. The drills have since changed, but the objective remains the same. If you have any trace of claustrophobia or fear of drowning, the clever instructors will find it. They will push that button again and again until you forever ignore it or quit. The brain has special circuits to warn you that you are dying and cause panic. Key West teaches you to turn them off.

There is no try. Every man in my class who failed to graduate quit in pool week. Whereas in Ranger School, there were hours and miles between meals where you thought about how powerfully hunger sucked.

Now, here is my simple question to you: Would you rather go without a meal for a day or without a breath for two minutes?

The first week, they issued full open circuit gear, complete with twin 80-cubic-foot tanks. While we got plenty of experience donning and wearing these primitive behemoths, we did not turn on the air and use regulators until week two.

My least favorite exercise was bobbing, where you jumped up from the bottom of the deep end with your fins on your hands, got your head above the surface, took a breath, and went back down. Repeat until told to stop. The purpose of this drill was explained several times, but the story was never the same twice and never made any sense. I did this correctly only once, on test day.

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There was another drill called crossovers. Half the class would line up on each side of the long axis of the Olympic-sized pool. At that point, there were about 25 guys still in the class. They would push us into the deep end so everyone was crowded and with Twin 80s, BCD vests, mask and fins, and weight belts, we clung to the edge of the pool.

On the cadre’s whistle, you let go, pushed off and swam underwater to the other side. One side went low and the other went high. The low guys tried to stay as high as they could so they used less energy. The perils of this drill included running head-on into an opposite swimmer, causing both of you to lose all momentum, or having the guy next to you take your mask off with his push-off arm stroke.

Everybody wanted to get as far from the wall as possible to save on breath. But when they would put you in, you couldn’t move that way because you didn’t want to screw your buddies, so there was a natural rotation. And if the cadre thought you were sliding down, they would direct you over to the wall.

The cadre with the whistle controlled the pace. He could drive you as far into oxygen debt as he wanted. We almost cheered every time somebody lost a mask because they had to swim down and get it, and we all got an extra breath. The secret was to remain calm and breathe deeply with the time you had.

Hyperventilation prior to diving depletes carbon dioxide in the system, leaving a diver susceptible to shallow-water blackout. There is no warning sensation, and victims typically drown quietly. The cadre were very familiar with shallow-water blackout and watched for it constantly. There was a designated safety officer who counted heads and made sure everyone resurfaced. Problem was, he didn’t control the whistle.

Staff Sergeant Chuck Gates was an active-duty Green Beret from 19th SFG in Utah. He was quiet and in great shape. He blew through the PT test and had no fear of anything through pool week. I overheard the cadre mentioning that Chuck was a recycle. He had recycled because of crossovers. I asked him about it. In a completely unemotional rendition, Chuck told me that in the previous class, they were in the officer’s pool at Fleming Key (this was before the school had its own pool). The water was hazy, and they could not see the bottom of the pool. That is where he nearly died.

Chuck didn’t remember much about crossovers from that day, so I got another version from one of the cadre I knew:

On that day, as the class was crossing the pool, they somehow provoked the ire of the whistle guy by probably displaying too much affinity for normal breathing.

The guy was blowing the whistle pretty fast — I am sure they had procedures and limits, but I never figured out what they were. The safety cadre guy missed a headcount because the pace was so quick. The second count was one guy short, but the class was back underwater before he could stop them.

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Chuck sank peacefully to the bottom of the pool, his airway completely obstructed by a swimming pool full of water. They finally stopped the drill and pulled the lifeless body of Chuck Gates from the bottom. He was not breathing, had no pulse, and had water in his lungs.

If you have never worked with an SF medic, they are a wonder to watch. Cool under pressure, they move with no doubt that they can fix any medical problem from arterial bleeding to syphilis. With boring efficiency, they raised Chuck from the dead and got him breathing again. Just another day’s work.

Chuck remembers the story again from this point onward. He was resuscitated and saw a bright light approaching. Brought back from the dead, the first words he heard were, “Do you want to quit?”

Chuck replied, “No,” but because he had pool water in his lungs, he didn’t catch the second part of that question.

“Well, get back in the pool.”

Say what you want about any other class anywhere in the world. There are plenty of other classes in which students die. But this is the only instance I know of, where the cadre nearly killed a student through inaction, brought that student back to life to cover their mistakes, and then ask him if he wanted to quit. If you have a better story, I want to read it.

Now, I trust the Army and the John F. Kennedy Special Warfare Center, but I am only going to let them drown me once. If I am revived and offered a chance to quit, I am going to take it.

Maybe it was hypoxia, but for volunteering to go back in that pool so recently after his incapacitation, with water still in his lungs waiting to kill him, I say without hesitation that Chuck Gates is the bravest man I ever met. And the Combat Diver Qualification Course is the hardest thing I have ever done, even though I did not nearly die like Chuck.