Fierce winds ripped at the sails, pushing his vessel harder into the crashing swells. For hours, Stamm endured life-threatening conditions.
His body took a beating, his mind pushed to the limits as he fought for survival. Ice cold splashes of seawater helped Stamm stay awake. Veins pulsing with adrenaline helped keep him on top of each task.
When sailing in the Velux 5 Oceans--a nearly 30,000-mile, solo, around-the-world sailboat race currently on layover in Norfolk--the wrath of Mother Nature is the obvious enemy.
But the real beast in the belly of the boat is sleep deprivation.
Fatigue: The Real Enemy at Sea
"Sleep is what messes with my head...with everything," said Stamm, who won the previous edition of the race five years ago. Stamm leads this year's field that departs Sunday for the final leg.
The second leg took Stamm just short of 49 days. Other competitors have sailed for more than 75 straight days.
"Being too tired transforms reality. It is something that always exists in this race," said Stamm, his hands roughened and his skin tanned from months at sea. "That transformation can be scary."
Stamm, of Switzerland, knows as much as anybody how scary such situations can be.
As seas started to calm after that frightful day in the first leg of the current race, things really started to get bizarre for Stamm.
He was exhausted from the relentless battle with the sea. It had been nearly a day since he had snuck in one of the 20- to 40-minute catnaps that keep him functional.
Stamm had hung his foul-weather gear on the mast boom to dry before getting ready for another short nap. But before he closed his eyes, he glanced back at the gear and thought he saw another person on board.
"Where did this person come from and what were they doing on my boat?" Stamm recalled thinking. "I got angry because he wouldn't answer me when I yelled, 'Who are you?'
"I was hallucinating. I guess it lasted about 10 seconds. It seemed like much longer."
Stamm managed to pull himself together, rest and put the scare behind him.
Others in similar endeavors haven't been so lucky. Sailors have had to be rescued at sea.
While competing in the 1968 Golden Globe solo race, Donald Crowhurst committed suicide. A lack of sleep, race officials at the time said, likely was a key factor.
Delirious, Crowhurst realized that he and his vessel were ill-prepared for the journey. So he set in motion a wild scheme to make it look like he had been sailing around the world. In actuality, he merely had been sailing in huge circles in the Atlantic, trying to avoid contact with any other vessel that might identify him.
After weeks of writing a bogus logbook, Crowhurst concluded that he likely was going to be caught. In notes left on the boat, he said the humiliation of what he had done was too much to endure.
So he simply walked off his boat and drowned.
His boat was found months later, adrift in the Atlantic.