Demystifying Ratings and Handicaps for your yacht
By Dara Totterdell
Anyone who takes part in any level of yacht racing would find the concept of racing two different boats together without affecting some sort of equalising system both unfair and invalid. Rating and handicapping our boats so they can race together has been employed for as long as yacht racing itself. However, we have come a long way since simpler times and, to my mind, ratings and handicaps might just be the one last cause of confusion in a world where most things are explained by a quick trip to Dr Google!
For a displacement hull, the most important principal is that maximum speed is limited by waterline length. The waves created at both the bow and stern affect the ‘hull speed’ and this is demonstrably lower for shorter boats than longer boats. Other things affect the ‘hull speed’ too, such as the surface area of the hull, rudder & keel; the weight (or displacement) of the yacht and the sail area. A rating system is based on finding ways to measure & represent these variables numerically. A modern rating system will combine the variables mathematically depending on different designs, and the subsequent rating will be represented as a ‘Time Correction Coefficient’( TCC). In most systems it will be a number slightly more or less than 1. In a race which is scored with this system, the boat’s TCC is multiplied by the elapsed time, and thus the corrected time is calculated.
Handicapping systems take this to the next level. In a series of races where all boats race together, in the same wind and around the same course, it will become clear that, despite the application of a TCC for each yacht, some consistently do better than others. The difference, of course, is that one boat might be sailed more competently than others. A yacht handicap system tries to take account of this. ECHO, for example, takes account of a yacht’s performance throughout a series and after a few races, it changes the TCC to reflect the actual performance of the yacht AND the crew. The aim of a handicap system is to give every yacht in a mixed fleet an equal chance of winning. No rating or handicap system is perfect. There is now quite a collection of systems in use throughout Europe and US. As a consequence, Irish Sailing have established a Handicap & Ratings Steering Group (HRSG) to provide clarity to any club looking to try a system of their choice.
IRC and ECHO
Here in Ireland, most clubs will use IRC ratings; ECHO handicapping & now, increasingly, VPRS rating. It is expected that every yacht that races using these rating systems will have a valid certificate for that year which can be produced when asked for by event authorities.
IRC is a World Sailing recognised International Rating Certificate( IRC). Although all certificates are processed by RORC, Irish Sailing is the authorised administrator of the system here in Ireland. It provides a rating based on measurement and data input only, for boats with a minimum hull length of 5.00m. The IRC rating is calculated as a TCC to 3 decimal places. All boats are issued with an IRC cert with 2 ratings: spinnaker and non-spinnaker.
VPRS ( Velocity Prediction Rating System) offers yacht clubs a system based only on measurement data. This data is used to configure a Velocity Prediction Programme (VPP) which predicts a boat’s speed for a range of winds and directions, and with this data it calculates a TCC. It is currently being used here in Ireland by DBSC sportsboat class instead of IRC. A list of VPRS- rated boats is given on www.vprs.org website.
ECHO (East Coast Handicap Organisation) is a performance handicap system for yacht racing designed in Ireland. An ECHO handicap is derived from the performance of the boat and crew and assumes that past performance is a guide to future performance. A boat is issued with an ECHO opening handicap, (Standard ECHO: derived from historical IRC data and bears no relationship to performance) at the start of the event. Thereafter, following a race, the yacht’s elapsed race time is multiplied by a Time Corrected Factor( TCF) and the boat with the lowest corrected time is the winner. Progressive ECHO sees the TCF changing to reflect the performance of the yacht throughout the series. The premise of this system is that every boat should have a chance of winning an individual race & that the fastest boat should have the highest handicap. www.sailing.ie has a page dedicated to calculating this system. The HRSG, contacted through Irish Sailing, are available to help with problems which can arise with occasional participants or new boats entering under this system.
Other interesting new systems that are currently being watched by the Handicap & Rating Steering Group are the RYA YTC, which provides British sailors with a simple rating assessment which is both cheap and easy to apply. This is currently not available here but watch this space! Some of our more involved interested parties in this area would feel that ORC, used in Kiel Week as well as other prestigious international regattas, is the gold standard of ratings. Certainly, when it comes to multihulls or superyachts this would be the rating of choice. ORC (Offshore Racing Congress) systems use the International Measurement System (IMS) as a measurement platform alongside the ORC Velocity Prediction Programme (VPP) to rate boats. Needless to say, this consummately professional system comes at a cost which, for our needs, does not seem justified at present. www.orc.org has all the information regarding this system.
PHRF (Performance Handicap Racing Fleet) is very widely used in North America. The handicap number assigned to a class of yachts is based on the yacht’s speed relative to a theoretical yacht with a rating of 0. A yacht’s rating is the number of seconds per mile travelled that the yacht in question should be behind the theoretical yacht. Most boats have a positive PHRF rating, but some fast yachts may be negative.
PHRF races can sometimes take the form of pursuit races, or reverse handicap racing. Boats start in reverse PHRF order with start times staggered based on PHRF ratings. This means that theoretically, all boats should finish at the same time which makes for an exciting finish! This means that the boats cross the line in order of placement in the race.
Time on Distance (ToD) racing is not commonly employed in Ireland. For this to work, we need to accurately measure a distance to be raced, which is not as easy as it sounds. It is the time taken to travel that known distance that is multiplied by the TCC. Most event directors go with Time on Time ( ToT) racing which has a fleet racing over elapsed time. It is this figure which is multiplied by TCC to get the corrected time.
Irish Sailing Handicap and Rating Steering Group
For whatever reason, this area of sailing is utterly fascinating to us on your Handicap & Rating Steering Group! We have been in existence since 2020 and would acknowledge that no question is without merit. We meet a few times each year, usually outside racing months and we are delighted to help and support any club wishing to set up and run events using handicap systems anywhere in Ireland.
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