9th February 2015

With so many varied handicap and rating rules around the world it would be no surprise if owners in some countries feel as though they are pulled in all directions when it comes to making a choice. Of course the rating or handicap needed depends upon that selected by the event, which again may be a tough decision. So, why should owners and event organisers choose the Spinlock IRC rating rule?

IRC has stood the test of time and is truly global. It is a 30 year old International rule, used in over 30 countries on all six continents, and issues over 8200 certificates a year to 6200 boats. The certificate is valid not just for a club’s own races but also for open events at other clubs. For the globetrotters, a boat holding an IRC certificate in Europe can race with the same certificate in the USA (or Australia, Japan or South Africa or anywhere else in the world …). All certificates are processed either by the RORC Rating Office in the UK or the UNCL Centre de Calcul in France, ensuring a high degree of consistency. We are proud to offer a top class service to owners and event organisers.

NeillRoss 3boat s

photo: Neill Ross

IRC never stands still.   IRC is a ‘live’ rule and the formulae are developed annually to take account of design trends and adjust for fairer rating of generic features. IRC is a forward-thinking rule and over the last three decades has led the way in permitting new features. IRC will rate virtually any single or twin masted, ballasted monohull, and will rate as equitably as possible features such as asymmetric spinnakers and bowsprits, canting keels, twin, triple, wing and drop keels, gaff rigs, rotating masts, water ballast, canting keels, ‘code zero’ headsails, composite rigging, lateral daggerboards and DSS… the list goes on!

Of course, most of the fleet are cruiser/racers with relatively standard features and configurations, and those owners can remain confident that IRC protects the fleet and boat values as it is an unpublished rule. There will always be critics of the fact that the IRC formulae are vigorously protected and claim it as a weakness in a rating rule. The truth is the exact opposite!

The unpublished nature of IRC prevents designers taking advantage of the rule when designing new boats and very substantially increases the competitive lifetime of IRC rated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, from classics through IOR designs to modern cruisers, cruiser/racers, and full-on racers.

six14-1813 quokka8 rc600 cred s

photo: RORC/Tim Wright/photoaction.com

IRC produces balanced boats and caters for diversity. All rating rules typeform to some extent and IRC encourages well balanced all-round designs without ugly distortions, suited to both inshore and offshore racing and with a reasonable interior for those non-racing needs. IRC also actively discourages modifications to production boats, believing that owners should not have to strip furniture out of their boats to remain competitive. Recently there have been suggestions in the media that IRC cannot cope with a diversity of design types at particular lengths. Catering for all ages and types of sailing boat is what IRC does very well for the vast majority of the fleet. The problem for any rating rule that is trying to rate a wide variety of boats of the same size, is that budgets between, for instance, an old 50 footer and a relatively new TP52 are so different that this alone is going to make as much, and probably more, difference than the choice of rating rule.

It is simple to calculate results.   An IRC rating consists of a single number Time Corrector that applies no matter what the course, wind speed or tide. Therefore both owners and event organisers can very quickly and easily calculate corrected times, both at the end of the race and on the water at points around the course. We encourage event organisers to set a variety of courses so that no one type of boat is favoured.

Application is simple and does not usually require official measurement. Owners simply fill in the form and submit it to their local IRC Rule Authority. We hold standard hull data for over 1000 designs. Rig data will come from the boat’s specification and the sailmaker will be able to supply the sail dimensions. Unless an event or Rule Authority require Endorsed (i.e. officially measured) certificates, NO official measurement is required.

irl rbateman cred s

photo: R Bateman

Event organisers - join the list of popular regattas around the world! As a taster, as well as the thousands of local club races, IRC is used at (among many others) well known events such as: JPMAM Round the Island Race, AAM Cowes Week, Rolex Fastnet Race, Volvo Cork Week, Voiles de St Tropez, ARC, Rolex Middle Sea Race, Rolex Sydney Hobart Race, Audi Hamilton Island Race Week, Dubai-Muscat Race, Rolex China Sea Race, RORC Caribbean 600, Raja Muda Selangor International Regatta, New York YC Annual Regatta, Phuket King's Cup, Spi Ouest France, Maxi Yacht Rolex Cup and Maxi 72 Rolex World Championship, Volvo Dun Laoghaire Regatta, Block Island Race Week and the RORC's Brewin Dolphin Commodores' Cup. Notes for race organisers in the annual IRC Yearbook and daily updated rating lists available on our website make running races easy. If you need further advice, we are always here to help.

If you are an event organiser or ISAF Member National Authority and would like to find out more about Spinlock IRC rating, please see www.ircrating.org and contact the RORC Rating Office on or call +44 1590 677030 with any specific enquiries.

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Header images by:

John Crawley (CAN IRC)  
Jinno (c/o JPN IRC)
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