Masterpiece: Olin Stephens’s Radical Yacht — Dorade is 75; its maker is 98 — and they both remain (sea)worthy of admiration

OLIN STEPHENS’S obsession with sailboats took hold shortly after World War I during a childhood visit to Cape Cod. He didn’t just admire them. He studied them with what he later described as “great concentration,” sketching any he thought might be worth emulating and imagining how he might do things differently.

By the time he was 20, Mr. Stephens had dropped out of M.I.T., had brief apprenticeships with several leading yacht designers, drawn up plans for a handful of small boats, and formed his own company, Sparkman &Stephens. On the basis of Olin’s early promise, his father, who had recently sold the family coal-supply business, placed an order for a relatively large yacht, a 52-foot yawl. When Dorade, named for the dolphin that is correctly spelled Dorado, was launched in 1931, it sparked a revolution.

It was strikingly slender, its beam just 10-foot-3. It was also, by the standards of the day, extremely lightweight, in part because the frames that supported the hull were made from steam-bent sections of wood weighing far less than conventional and much bulkier sawn frames. Until then, it was believed that ocean-going stability could not be achieved without a much broader and heavier hull. Dorade’s stability came from a different source — a lengthy lead keel that put the ballast far below the waterline, where it would be much more effective in counterbalancing the force of the wind.

Thanks to the combination of a streamlined hull and “outside ballast,” Mr. Stephens was certain Dorade would be fast. It was also strikingly beautiful. Like most designers of that time, he believed boats that were pleasing to the eye were also faster than unattractive ones. Dorade’s bow and stern rose from the water with curvaceous grace, creating the elegant overhangs that are hallmarks of classic sailing yachts.

BUT DORADE REPRESENTED a major risk. Mr. Stephens had created a radical new design without the computer analysis and tank testing that is now commonplace. He had relied upon instincts alone, intuitive judgments of how a vessel’s lines would affect its performance. The lack of precision was obvious the moment Dorade was launched: The white stripe that had been painted around the hull to mark the waterline disappeared as it sank three inches below the surface. When Mr. Stephens announced that he was going to enter Dorade in a trans-Atlantic race, many yachtsmen thought he was foolhardy.

Mr. Stephens was the skipper and navigator during the race, which set out for England from Newport, R.I., on July 4, 1931. His seven-man crew, which included his younger brother Rod, who had overseen the yacht’s construction and would become a partner in Sparkman &Stephens, was young: Even with the inclusion of the Mr. Stephens’s 46-year-old father, the average age was just 22.

Olin Stephens was at the helm when Dorade crossed the finish line on July 31. Longer sailboats generally go faster than shorter ones, but Dorade, the third smallest of the 10-yacht fleet, reached the line more than two days before the second-place boat. When the times were handicapped, or “corrected,” to reflect the differences among the yachts, Dorade’s time was almost four days better than its closest rival. Dorade went on to win the Fastnet Race by a wide margin. When the crew returned to New York City, where Sparkman &Stephens had its office, they were rewarded with a ticker-tape parade, a first for sailors.

And yacht design would never be the same. The assumptions that had limited naval architects to incremental advances were abandoned and the modern age of racing design, defined by an endless quest to produce lighter but more powerful yachts, commenced. No one benefited from this more than Mr. Stephens, who became the most successful designer of the 20th century, creating plans for six successful America’s Cup defenders, two of which were two-time winners.

Dorade also became a legend. The Stephens family sold it in 1936, but successor owners have underwritten the ceaseless work of maintaining an aging wooden vessel. In recent years, it was based in the Mediterranean, where an Italian owner competed in Europe’s active classic yacht racing circuit. But since it was acquired by Edgar Cato, an accomplished American yachtsman, about a year ago, it has been based in Newport. “It was a piece of history that I had read about for most of my life — and I decided that I wanted to bring it back to the United States,” Mr. Cato explained.

Over Labor Day weekend, he and Mr. Stephens, now 98 but still traveling to yachting events around the world from his home in Hanover, N.H., boarded Dorade to compete in the Museum of Yachting’s annual Classic Yacht Regatta in Narragansett Bay. Although Mr. Stephens himself advised the crew on the most favorable sail combinations, Dorade placed second after a section of the rigging failed in winds gusting to more than 30 knots. “We would have won otherwise,” said Mr. Cato, who plans to continue racing Dorade in the Caribbean and New England.

Unfailingly modest, Mr. Stephens is reluctant to rate Dorade as a masterpiece. When I spoke to him a couple of weeks ago, he said it was too narrow, that it would go even faster, and be less “rolly,” if he had given it just a bit more breadth. But he acknowledged that Dorade was a breakthrough — or, as he put it, “a kind of awakening” — for yachting design. “I knew that a lighter boat with outside ballast was the way to go, and that a deep and narrow hull would go through the sea nicely. It was obvious. It was like taking candy from a baby. It just had to win.”

Mr. Knecht is a Journal reporter and the author of “Hooked: Pirates, Poaching and the Perfect Fish.”