What is a rating ?
Boats who wish to race need to obtain either a "handicap" or a "rating" so that they can race fairly with boats of different designs.
A "handicap" is a system, usually locally administered, which allocates a time allowance to a boat to reflect its performance on the water. This allowance can be reviewed based on actual performance and race results.
A "rating", on the other hand, is a time corrector based on the measurements of the boat, rig and sails, and takes no account of crew ability or race results.
What is the IRC rating rule
IRC is a rating rule to handicap different designs of keelboats allowing them to race together. Each boat’s rating (her ‘handicap’) is calculated using measurements of the boat; her length, weight, draft, sail area, etc. The resulting time corrector, the boat’s ‘TCC’, is her handicap. After a race, each boat’s elapsed time (the time she has taken to complete the course) is multiplied by her TCC to calculate her corrected time (her race time making allowance for the characteristics of the boat). The boat with the shortest corrected time is the winner of the race.
IRC is for keelboats of all size and shapes
IRC is aimed at a very wide range of keelboats of all sizes and shapes including modern production cruisers and cruiser/racers through dedicated one-off race boats, older cruisers and racers to classic yachts and superyachts. IRC is continually developed to encompass new developments in both cruisers and racers while at the same time protecting the interests of the bulk of the fleet.
IRC is a permissive rule
It is open to all types, sizes and ages of boats. IRC permits features such as asymmetric spinnakers, bowsprits, water ballast, canting keels, ‘code zero’ headsails, etc, and deals with these features as equitably as possible alongside more conventional boats.
IRC is a secret rule
The methods used for the calculation of IRC TCCs are kept secret by the IRC administrators. This prevents designers taking advantage of the rule when designing new boats and very substantially increases the competitive lifetime of IRC rated boats. As a result, boats of all ages and types win races under IRC. Everything from classics through IOR designs to modern cruisers, cruiser/racers, and racers.
IRC is a simple rule
IRC is structured to be as simple as possible for both sailors and race administrators: there is no requirement for boats to be officially measured. IRC accepts owner declaration of a boat’s measurements. All an owner needs to do is fill in the application form and send it to us.
IRC is popular
IRC is used for a huge number of races and regattas. Apart from local races, IRC is used at (among many others) Cowes Week, Fastnet Race, Cork Week, Voiles de St Tropez, Key West Race Week, Atlantic Rally for Cruisers, Middle Sea Race, Sydney to Hobart Race, Hamilton Island Race Week, China Sea Race, Philippines Presidents Cup, Phuket Kings Cup, and the Commodores’ Cup. In 2008 nearly 7500 boats in 30+ countries on all 6 continents held IRC certificates.