'You can't panic,' boater says of how he survived Tropical Storm Debby while adrift in the Gulf

Veteran sailor Nathan Thomas said he and a friend survived a harrowing close encounter with Hurricane Debby off the Gulf Coast of Florida on Sunday after they lost the main sail of a sailboat he had just purchased and were suddenly adrift in 20-foot-plus waves.

The 69-year-old Thomas described the experience to ABC News on Monday as "like being in a washing machine" as he and his sailing partner, Adrian, waited for nearly three hours to be rescued by the U.S. Coast Guard after they made a desperate SOS call.

"I knew that if the Coast Guard didn't get to us, we had less than a 50% chance of surviving. I knew that," Thomas said in a telephone interview.

Thomas said he had just purchased the 34-foot sailboat for $5,000 and picked it up in Marathon, Florida, on Wednesday. He said he was sailing it back to the Tampa area where he lives and thought he could make it home ahead of Debby.

"The storm came across faster than I anticipated. I knew it was there, but I thought I could beat it," Thomas said. "I played the cards and guess what? I gamble wrong. I lost that hand."

He said his friend, a retired Merchant Marine, was operating the 40-year-old sailboat, which Thomas described as a racing-style boat that "pivots on a dime." He said his friend, who was not used to operating such a vessel -- which the previous owner christened the "S/V Journey" -- overcompensated as he steered it, causing a steel cable to suddenly snap. The main sail was then rendered useless, causing the men to be set adrift in 20-foot-plus seas.

"You can't panic. That's the last thing you can do," Thomas said. "If s--- goes wrong, maintain it. Be in control. Even though it goes wrong and stuff, you still have to maintain what's going on. The minute you panic, it's over for you."

Thomas said when they lost their sail at about 8 a.m. Sunday, he and Adrian were in the Gulf of Mexico about 35 miles northwest of Clearwater, Florida, and 35 miles southwest of Tarpon Springs, where they were headed. At the time, Debby was a tropical storm picking up speed as it approached the Florida Panhandle area.

U.S. Coast Guard officials said they had already launched rescue aircraft by the time Thomas was able to reach them on his radio on Sunday.

A friend of Thomas' contacted the Coast Guard station at St. Petersburg around 5 p.m. on Saturday to report the boaters had missed their check-in while sailing up from the Florida Keys to Tarpon Springs.

"Some of the most important factors in any rescue case is accurate information and safety equipment," said Lt. Cmdr. Christopher Hooper, a search-and-rescue mission coordinator for Coast Guard District Seven in Florida. "We received an updated satellite position from the boaters' friend, which led us to them being successfully located."

The Coast Guard confirmed to ABC News Monday that the two stranded boaters were found adrift in 15- to-20-foot seas and 50-knot, or about 60 mph, winds.

While visibility at the time was only about a half-mile, a fixed-wing rescue aircraft sent to search for the men was able to find them, according to the Coast Guard. An MH-60 Jayhawk helicopter arrived and completed the rescue.

"The fixed-wing found us and circled us until the helicopter snatched us out of the water," Thomas said.

As his friend was being hoisted to safety, Thomas said he went below deck and opened the seacock, or a valve on the hull of the vessel, to sink the boat, adding that it had diesel tanks and oil aboard, as well as about $10,000 worth of electronic equipment, including sonar. He said he sank the boat to prevent it from running aground in a protected nature preserve.

"I scuttled my own boat is what I did," Thomas said. "I'm not going to have my boat run ashore in some protected area."

Debby made landfall as a Category 1 hurricane with 80 mph winds around 7 a.m. Monday in Florida's Big Bend region.

"I never thought I would ever have to be rescued," said Thomas, who has been sailing since he was 17 years old. "When I was rescued, I told the Coast Guard, 'I never thought I'd be rescued by you guys. I've been through too many storms, and this storm actually got me.'"

Thomas said the ordeal has not dampened his love for the sea.

"I'm getting another boat, trust me," Thomas said.