Supermaxi

A maxi yacht usually refers to a racing yacht of at least 70 feet (21 m) in length.

The term maxi originated with the International Offshore Rule (IOR) rating system, which in the 1970s and 1980s measured offshore racing yachts and applied a single-number rating to each boat. This number was approximately equal to the sailing waterline length in feet, plus or minus speed enhancing or reducing factors in the design. A yacht with a rating of 40 feet (12 m) was generally about 47 to 52 feet (14 to 16 m) in length overall. The IOR had upper and lower rating limits of 16 feet (4.9 m) and 70 feet (21 m), so a yacht designed and built to the maximum limit of 70 feet (21 m) rating was known as a maxi.

Being the biggest sailing yachts afloat, Maxis have always had the best chance of finishing first. They were sufficiently fast and seaworthy to cross oceans and became the craft of choice of pioneers of the Whitbread Round the World Race. The racing giants in the Maxi Yacht Rolex Cup 2005 are the modern descendants of those early aquatic thoroughbreds.

The IOR Maxis were generally 75 to 82 feet (23 to 25 m) long overall, and raced boat-for-boat without handicap, unlike the rest of the IOR fleet which raced with a time correction factor depending on the boat's rating. In the 1980s they were the most glamorous, exciting, expensive and high-visibility racing yachts in the world, with regular appearances at most of the great races such as the Fastnet, Sydney-Hobart, Bermuda Race, and their own private series of regattas in the Mediterranean and Caribbean seas. The maxis were also prominent as line honour contestants in the Whitbread Round the World Race from 1973 to 1993.

Modern Maxi yachts are usually custom-designed and built to the IRC rule but regardless of handicap in order to achieve line honour victories. In 2001 however two 86 ft Reichel/Pugh boats were built to the "maxZ86" class in order to match boat speed evenly, but the class did not generate further interest. For the 2009 Sydney to Hobart Yacht Race, the Cruising Yacht Club of Australia increased the IRC rating upper limit for length of hull from 98 ft to 100 ft, and most 98 ft yachts have been lengthened to this size. In order to achieve higher speeds, Maxi yachts were early adopters of modern materials and technologies such as carbonfiber, thermoformed sails, rotating wingmasts, water ballasts and canting keels. Previous smaller Maxi yachts are still raced with corrected time class victories in mind whilst the 72 ft "mini-maxi" yachts now have a class of their own. Maxi yachts are raced in both inshore and offshore races.

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