IRC (sailing)

IRC is a system of handicapping sailboats and yachts for the purpose of racing. It is managed by the Royal Ocean Racing Club in the United Kingdom through their dedicated Rating Office.

Technically, IRC does not officially stand for anything. Originally, “IR” was an abbreviation for International Rule. However, since the Rule at that stage was not recognized under International Rule (sailing), that name was not permitted. So RORC simply decided to keep the initials as the name, and even after IRC received International Rule recognition, the name remained simply IRC.

The IRC rule is not published, meaning the only bodies capable of calculating an IRC rating are the RORC Rating Office and UNCL Centre de Calcul in Paris (they are joint owners of the Rule). This prevents designers from attempting to design 'to the rule'. The earlier IOR was published, and often amended, resulting in widespread criticism for several reasons. Firstly, as the rule effectively dictated the nature of boat designs, amendments to the rule could result in older designs gaining less favourable ratings compared to their real world speed, making racing competitively more expensive. Also, the pressure to produce designs which performed well under the rule resulted in designers producing yachts with certain dimensions intentionally extreme, in order to gain an unfairly favourable rating. The production of yachts which were excessively light and beamy - what became the classic 'diamond' plan form of the IOR - was believed to impact safety, and was cited as a factor in the 1979 Fastnet race disaster. In theory, the IRC avoids these problems.

An IRC yearbook is made available at the beginning of January each year to holders of certificates from the previous year together with a rating revalidation form. Apart from the IRC rule, the yearbook provides help to owners applying for their certificates by way of diagrams and definitions, race management recommendations, useful names and addresses, articles from invited authors and much other relevant information.

IRC can apply a rating to any mono-hull yacht. It considers such features as asymmetric spinnakers, carbon masts, canting keels, and water ballast, all of which have been permitted for several years. Furthermore, the rule is reviewed annually in light of new developments and past results. On this front, RORC seeks and actively welcome input and comment from the users.

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