Lowell North, a five-time world champion and Olympic gold medal-winning sailor who was also the founder of North Sails, the largest sailmaker in the world, died on June 2 at his home in San Diego. He was 89.

His daughter Julie North said he died a day after having a stroke. She added that he had had several strokes in the past.

Mr. North’s string of championships in Star Class sailboats began when he was a teenager. From the start, he approached sailing as an engineer as well as an athlete.