Jan Jongkind began working as a sailmaker after World War II and eventually started his own business in that field. As his business expanded globally, he took up sailing himself, particularly in the Flying Dutchman and Dragon classes. He was the 1962 Dutch champion in the latter event and was selected to represent his country at the 1964 Tokyo Olympics. After two races, however, he got into an argument with his crewmate Wim van Duyl and exited the tournament. The Dutch team eventually placed 13th and both men were banned from international competition for two years by the national federation. Jongkind remained active in the sailing business for many years thereafter, but also engaged in a variety of other ventures and earned a pilot’s license.