Thirty years ago in 1988 the Channel Handicap System, now named IRC, introduced its own Safety and Stability Screening (SSS) system to help race organisers decide on a boat’s suitability for a race from a stability perspective. All IRC rated boats still have a calculated SSS value printed on the certificate, with a higher number indicating a more seaworthy boat.

The SSS value was never a pure ‘stability’ factor and CHS/IRC has never directly measured stability and avoids expensive inclining tests. The SSS calculation includes factors derived from principal dimensions and design characteristics that influence stability. One of the Rating Office Directors used to describe it as “How well would this boat take care of its skipper and crew in the event of an emergency?”.

"Wise words from James Dadd, director of the RORC Rating Office, who recently took a detour from his Australia/New Zealand tour to stop over in Samui during the Samui Regatta and talk with sailors and event organizers about the IRC rating system prevalent in this area of the world..."

Duncan Worthington reports for The Phuket Gazette from James Dadd's recent visit to Samui Regatta in Thailand, read the full report here:



rc600 timwright1The recent announcement of the 2017 Western Caribbean Series reinforces the position of the International IRC rating rule in the Caribbean and southern USA. With the easing of travel restrictions to Cuba for American sailors in December 2014 after 50 years, clubs in the area are welcoming the new opportunities for offshore races.  

IRC sailors will be spoiled for choice in the north western Caribbean in early 2017 with different offshore options to choose from after Quantum Key West Race Week in January.

During James Dadd's recent trip to New Zealand, Australia and SE Asia, yet again the question of course types came up, and in some areas a reduction in entries for windward/leeward style races.

Here is an extract from the Advice for Race Organisers on this and other issues:


There has been much discussion in recent years concerning the dominance of windward/leeward courses and that many competitors find these either boring or not suited to their boats and crews. The IRC Technical Committee also considers that if all races were windward/leewards designers would inevitably optimise designs for this style of racing, eg. heavy, narrow designs with poor reaching performance.

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Header images by:

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