SAN FRANCISCO – A century-old tradition, the Full Crew Farallones Race has never been for the faint of heart: Winds averaging 10 to 20 knots and churning 14-foot Pacific Ocean swells are among the rough conditions typically braved by yachts and their crews during the daylong regatta, a spring favorite of skilled sailors.

But on Saturday, powerful waves and a disastrous series of events brought rare tragedy to the august race and the San Francisco Bay area’s large sailing community.

One crew member died and four others remained missing at sea Sunday after two strong waves swept them from their boat near the rocky Farallon Islands, the halfway point of the 54-mile race that began at daybreak in San Francisco and had 49 entrants.

It was the first known fatality in the 143-year history of the San Francisco Yacht Club, which managed the race for the Offshore Yacht Racing Association and where the yacht involved in the accident, the 38-foot Low Speed Chase, was based, club director Ed Lynch said.

“The race community is a very tight-knit group of people, and obviously this tragedy has reached far and wide around the world,” he said. “It’s an event that will give everybody pause.”

Low Speed Chase’s owner and captain, James Bradford, 41, of Chicago, was among the three survivors whom the Coast Guard, aided by National Guard helicopters, pulled from one of the islands about 300 feet from their damaged craft, Lynch said.

Bradford and another crew member were briefly treated at a hospital, while the third survivor remained hospitalized with a broken leg and bruises, he said.

The eight people on board ranged in age from their 20s to their 40s, Lynch noted. He said the San Mateo County Coroner’s Office has identified the crew member whose body was pulled from the water as Marc Kasanin, 46, of Belvedere, Calif.

The crew members who are still missing are: Alan Cahill of Tiburon, Calif.; Jordan Fromm of San Rafael, Calif.; Elmer Morrissey, who is from Ireland; and Alexis Busch of Larkspur, Calif., the only woman aboard the Low Speed Chase, Lynch said.

Lynch said the yacht club, which is just over the Golden Gate Bridge from San Francisco in Belvedere, has 1,400 members and is a place where “lawyers, carpenters and doctors can all have a beer together and talk about their love of sailing.” But Saturday’s race was likely to attract the most dedicated recreational sailors, he said.

The Farallon Islands are “certainly some of the toughest conditions around in a sailing environment,” Lynch said. “It’s not for everybody, but for the people who do it, it’s a thrill.”

The conditions during Saturday’s race were typically rough, but Low Speed Chase ran into trouble when it was broadsided by a large wave and some crew members were swept overboard, he said.

As the boat was turning around to get them, a second wave flung all but one of the remaining crew members into the water and the yacht aground, Lynch said. The crew of another boat in the race witnessed the accident, but was unable to render aid, he said.

A mayday call went out about 3 p.m. Saturday, Coast Guard Petty Officer Levi Read said. On Sunday, three helicopters, a surveillance plane, two patrol boats and a larger cutter were searching a 15-mile-by-30-mile swath of water around the islands, as well as shoreline areas.

The entire crew was believed to have been wearing life vests and cold weather gear, making rescuers optimistic they may find more survivors, Read said.

The Farallon Islands are a series of steep, rocky outcroppings that are uninhabited except for a manned research station. Part of a national wildlife refuge and closed to the public, the islands are home to vast numbers of sea birds and are surrounded by waters rich with seals and sea lions, as well as the sharks that feed on them. Search crews have not reported seeing sharks, Read said.

The wreckage of the Low Speed Chase remains grounded on one of the islands while the search for survivors was continuing at least until sunset Sunday, he said.

University of California, Davis chemist R. David Britt, who skippered his sailboat, Split Water, in the Full Crew Farallones Race for the third time Saturday, described the sailing by the islands that day as “pretty intense.”

Swells nearing 20-feet-high were breaking far enough from the craggy outcroppings that Britt says he steered farther around them than he otherwise might have to avoid getting swamped by a wave or dashed onto the rocks.

“The worst thing is to have a wave break on you,” he said. “You can go up and down, up and down, but if a wave breaks on the cockpit on top of the crew, that’s how somebody could get swept out of the boat.”

Britt thinks he was not far ahead of Low Speed Chase as they rounded the islands, and thought it strange when he looked back later and no longer saw his competitor.

During the day Sunday, people dropped roses and tulips by the entrance of the San Francisco Yacht Club, which hosted a members-only candlelight vigil and prayer service Sunday evening to honor the four missing crew members as well as the crew member who died.

Anne Kasanin, the mother of the sailor who died, attended the service and was touched by how many people knew her son, who started sailing at age 7 and lived his whole life on the cove where the yacht club is located. He was a well-known local artist whose landscapes in acrylic and oil reflected his love of the water, she said.

“He was a very dear son to me and a tremendous help, and I’m going to miss him very much,” she said.