The post-war revival
After the Second World War, the America's Cup had to reinvent itself. The last Cup took place in 1937 and was raced on the expensive J-Class, monsters of almost 120 feet and displacing nearly 160 tons.
The post-war economic reality requires trade unions to shift their choice to a cheaper class. In 1958, at the instigation of the British, it was proposed to compete for the Cup on 12m JI (International Class) yachts. The JI, or metric gauge, is an international racing gauge developed in 1906, allowing the performance of competition sailing boats to be evaluated.
12m JI, what does that mean?
12m JI does not correspond to a hull length, but to the result of a mathematical formula to be obtained by taking into account several criteria. The overall length of a 12m JI is between 18 and 21 m, for a displacement of approximately 30 tons.
Like other classes of the International Tonnage Measurement System, boats must comply with a measurement formula that takes into account the waterline length, the sail area and measurements taken on the hull dimensions. The result of the calculation according to this formula gives a theoretical length expressed in metres, which in this case must not exceed 12m.
The architectural and sporting quintessence
The 12m JI gauge will be used for the America's Cup from 1958 to 1987. This relatively free gauge will allow many architects to express their talents. Olin Stephens, Clinton Crane, William Fife III, Philip Rhodes, Philippe Briand and Ben Lexcen used the Cup as a laboratory to develop the best hulls. These numerous researches have allowed the validation of many innovations, which will be taken up in the world of yachting.
It is also at the helm of the 12m JI that match-racing acquired its letters of nobility. The world's best helmsmen have been competing at the helm of these boats for nearly 29 years, offering everyone duels of anthology.
The first edition on 12m JI is won by the yacht Columbia, which is helmed by Briggs Cunningham, inventor of the mainsail trimming system of the same name. The United States would then take all the victories for several decades. The New York Yacht Club will manage to impose its best helmsmen and lawyers until the early 1980s. The unthinkable happened in 1983 when a well-inspired Australian crew managed to take the Cup from American skipper Dennis Conner.
Led by the excellent John Bertrand, the 12m JI Australia 2 is equipped with a revolutionary winged keel, which will bring the Cup back to the southern hemisphere for the first time. If history has shown the interest of the fin keel on a 12m JI, its development on cruising yachts has not revolutionized the world of yachting.
A regatta format in place for 30 years
It was during the reign of the 12m JI that the Cup defined its current regatta format. For lack of having brought back the silver ewer in the hexagon, it is a Frenchman who is at the origin of it. It was under the impetus of Frenchman Marcel Bich, creator of the eponymous pen, that it was decided to organise a series of preliminary regattas aimed at choosing the challenger capable of facing the defender.
For two decades, this event was partnered with Louis Vuitton, before this company changed its business strategy and was replaced by Prada (which has also been involved as a challenger since 1999).
What happens to the 12m JI?
Nowadays, the 12m JI continue to sail on several circuits around the world. Of the 200 vessels built in this class, it is estimated that approximately 110 units are seaworthy around the world. On the French coastline, the boats led by Baron Bich often pass by Hyères or the Bay of Quiberon. The second-hand market offers a few units, for prices ranging from 60,000 to 300,000 euros.
