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IRC and its origins
Like all rules, the IRC is designed to organize fleets of heterogeneous yachts taking part in a regatta. The IRC (International Rule Club) is an international rule of English origin. In France, the Union Nationale de la Course au Large (UNCL) promotes it, and supervises the rules and controls. Abroad, the Royal Ocean Racing Club (RORC) manages the IRC.
The IRC has its roots in the Anglo-Saxon metric measurement culture, and in particular the Channel Handicap System (CHS), which was devised by RORC and UNCL in 1983. The IRC replaced the CHS in 1999, and in 2003 the International Sailing Federation recognized the IRC as an international racing rule.
This system of time compensation has become the norm at major national and international events. Admittedly, it doesn't affect many sailors, but you'll be able to use the same measurement certificate for all IRC events worldwide.
In France, there are regional IRC championships, the three main ones being the Atlantic Trophy, the Channel Trophy and the Mediterranean Trophy.
In Northern Europe, the Commodore's Cup is a national team race organized every two years by the Royal Ocean Racing Club (RORC). It brings together some of the best crews from England, France, Ireland, the Netherlands and Germany.
Nearly 7,000 boats race in the IRC worldwide. In Europe, most of the fleet is based in Great Britain. If you want to race in different countries, this is the most relevant gauge.
How does it work?
If you decide to enter one or more IRC regattas, you'll need to fill in an online form to obtain your boat's rating. This will be calculated on the basis of your boat's basic data and design details.
A mysterious mathematical formula will give you your TCC (IRC time correction coefficient), which is your IRC rating. It is rounded to the third decimal place, e.g. 0.973 or 1.055. Each boat's compensated time is calculated by multiplying its actual race time by its TCC.
Let's take a look at a practical case to understand. The UNCL issued me an IRC certificate with a TCC of 1.042. On 1 hour of real course, with the TCC corrected, we will in fact retain 62minutes 31seconds for the final ranking (60 minutes x 1.042 = 62 minutes and 31 seconds).
My playmate has a Bateau2 theoretically a little faster than mine, with a TCC of 1.055. Over 1 hour of real racing time, with the TCC corrected, he will have 63 minutes and 18 seconds of racing time for the final ranking (60 minutes x 1.055 = 63 minutes and 18 seconds).
In the jargon we say that Bateau2 me "must have time . So for Bateau 2 to be ranked ahead of me, it has to arrive at least 1 minute and 13 seconds before me. Have a good start! On your calculatorsâeuros!
A secret formulaâeuros?
The IRC gauge formula is said to be secret, because the methods and formulas used to calculate IRC TCCs are not published.
However, with experience, architects around the world have learned to identify the characteristics of a "good IRC boat", and can type sailboats so that the rating is as favorable as possible. It's fair to say that this rating influences the design of certain boats: "racing-cruising boats".
When you look closely, the ideal IRC boat is fairly conservative, and it rarely pays to deviate from the "average boat". For example, the system doesn't favor modern boat characteristics such as wide hulls and light, gliding displacements.
It's a gauge that can evolve, but at the moment, we recognize that the IRC is rather favorable:
- For boats with a narrow waterline
- With bow-tips rising out of the water and skimming arches
- Medium- and heavy-duty travel
- For moderately stable boats at the usual angles of heel
How to obtain your IRCâeuros measurement certificate?
With the IRC system, there is no referencing of standard boats that would have a corresponding rating, as is the case with the OSIRIS system. For example, if you have a Sun Odyssey 32i, there is no â??standardâ? IRC rating, so you'll have to measure and declare everything as if it were a new boat.
This is a prerequisite for the mathematical equation that will deduce the theoretical potential of your yacht. To fill in your online certificate, you'll need tape measures and plumb bobs to provide the required information: weight, hull length and beam (at waterline and overall), strakes (fore and aft), rig, appendages, sails... However, if your boat comes from a well-represented series, UNCL has standard hull data. This will save you some costly and time-consuming measurements, but you'll still have to go through the rig and sail measurements. Fortunately, your yacht master will be on hand to help and advise you on both the choice of sails and the measurements to be supplied for the measurement.
To shine in regattas, you need to optimize your TCC. With the 'Endorsed' certificate option, the data is verified - weighing and official measurements - by a certified measurer. In the vast majority of cases, having your boat measured with the option of an 'Endorsed' certificate enables you to reduce your TCC, but it does represent a significant additional cost.
An attractive new formula has recently been launched. You can now try your hand at IRC at a very modest price (?20) thanks to the SER certificate. It allows you to take part in a first IRC regatta before making up your mind.
Membership of PROPIRC, the association of owners of IRC-rated boats in France, is a prerequisite for obtaining your IRC certificate.
