He followed Bruce Farr in challenging accepted notions of offshore racing yacht design. World Sailing recognizes eleven classes of racing yacht. The result is a quicker, faster hull than more traditional racing yacht designs. He named it after the "Bona", his racing yacht. The Longtze is a Chinese design of racing yacht, of carbon composite construction. Numbers 725 to 767 were built by Oliver Lee Racing Yacht. He proposed to bring a 90-foot racing yacht for his challenge boat. Partridge is documented as being the world's oldest, still fully operational classic racing yacht. With any racing yacht, the largest contributor to variable costs are the sails. International America's Cup Class racing yacht. Lulworth is a racing yacht that was built in Southampton in 1920. The aluminium-hulled racing yacht was commissioned by the Swiss Ocean Racing Club. Customers include racing yacht builder Farr Yacht Design, and SpaceShipTwo builder Scaled Composites. Columbia was an American racing yacht built in 1899 for the America's Cup races. Volunteer was an American racing yacht built in 1887 for the America's Cup races.