The International Seven Metre Class is a construction class, meaning that the boats are not identical but are all designed to meet specific measurement formula, in this case International Rule. At their heyday, Metre Classes were the most important group of international yacht racing classes, and they are still actively raced around the world. "Seven" in class name does not, somewhat confusingly, refer to length of the boat, but product of the formula; 7 m boats are, on average, 13 meters long.
History The 7 m was used as an Olympic class during the 1908 and 1920 Olympics. The International Rule was set up in 1907 to replace earlier, simpler handicap system which were often local or at best, national, and often also fairly simple, producing extreme boats which were fast but lightly constructed and impractical. The rule changed several times in history. About 200 boats were ever built.
Rule development
1907 rule
Used from 1907 to 1917.
where = waterline length (LWL) = beam = chain girth = difference between girth and chain = sail area = freeboard
1919 rule Used from 1920 to 1933.
where = waterline length (LWL) = chain girth = difference between girth and chain = sail area = freeboard
Olympic results 1908 London Great Britain (GBR)Charles Rivett-CarnacNorman BingleyRichard DixonFrances Rivett-Carnac The second competitor failed to make it to the start. No further competition
1920 Antwerp Great Britain (GBR)Cyril WrightRobert ColemanWilliam MaddisonDorothy Wright Norway (NOR)Johann FayeSten AbelChristian DickNeils Neilsen No further competitors
References