Built according to the International Third Rule for the 196419th America?s Cup. The aim of Olin Stephens was to have in Constellation an improved version of Columbia with a further refinement of the keel area and an improvement of the equipment as lightweight as was admitted by the rule. She had the boom, the mast tip and also the winch drums in titanium; strain gages were placed over the entire boat in order to measure the dynamic loading under sail; mast and boom bent more than those of her competitors thus allowing a greater control on sails according to wind conditions. The relatively short keel was really the only thing extraordinary about Constellation lines; combined to a long waterline allowed to have a good speed in light winds. The first results of the defender trials were rather disappointing with American Eagle dominating the other competitors in the first half of the trials. The results came up thanks to a direct involvement of the Stephens brothers and the change of the skipper from Eric Ridder to Bob Bavier; in the second part Constellation faced up and dominated American Eagle in the final series easily defeating in the America's Match by 4-0 the British Challenger Sovereign.