|
International Measurement System
The International Measurement System (IMS) is a system of handicapping sailboats for the purpose of racing that replaced the earlier International Offshore Rule (IOR) system in the early 1990s. It is managed by the Offshore Racing Congress (ORC). In the sailing world it is usually referred to simply as 'IMS'. Synopsis IMS was the first yacht racing rule developed around the central idea of a Velocity prediction program (VPP). The VPP was a complex computer program that integrated continuous hullform information in order to predict a given boat's speed potential in a given wind velocity. Details on the VPP were openly available to the yachting community, in contrast to the earlier IOR system. Designers and boat owners much preferred this as they were able to design new yachts to maximise performance under the rule with a degree of certainty they had not enjoyed under the IOR rule. IMS is generally believed to have made significant leaps of progress forward from the IOR rule it di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Handicap (sailing)
Handicap forms for sailing vessels in Yacht racing, sailing races have varied throughout history, and they also vary by country, and by sailing organisation. Sailing handicap standards exist internationally, nationally, and within individual sailing clubs. Typically sailing vessel classes are defined by measurement rules, which categorise vessels accordingly into classes of vessels, and vessels compete within their class. Handicapping allows vessels to compete across classes, and also allows vessels and crews to compete based on performance and equipment on an equal basis, by adjusting the race outcome data, to declare a ''handicap'' (adjusted) winner as distinct from a ''line honours'' (first over the finish line) winner. For some national, international, and other yacht racing events, rules such as those of the International Racing Certificate known as the International Measurement System (IMS) or the Sportsboat rule (SBR) may be specified. Others exist in different countries. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Offshore Rule
The International Offshore Rule (IOR) was a measurement rule for racing sailboats. The IOR evolved from the Cruising Club of America (CCA) rule for racer/cruisers and the Royal Ocean Racing Club (RORC) rule. Rule context - past and present rating systems The IOR was superseded (in the early 1990s) by the International Measurement System (IMS) and CHS (since renamed IRC). While some IOR yachts race at club level under IRC in more or less their original form, others had major surgery to make them competitive within the new rules. Rule components The IOR concentrated on hull shape with length, beam, freeboard and girth measurements, foretriangle, mast and boom measurements, and stability with an inclination test. Additionally, the IOR identified features which were dangerous, or it couldn't fairly rate, and penalized or prohibited them. The measurements and penalties were used to compute the handicap number, called an ''IOR rating'', in feet. The higher the rating, the faster the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Offshore Racing Congress
The Offshore Racing Congress (ORC) is an international body for the sport of competitive sailing and is responsible for the establishment and maintenance of rating and classification standards used to define offshore, that is marine as opposed to inland, yacht racing handicap categories. Ratings and Classification The ORC was established in 1969 to create a single international handicap standard to combine the two pre-existing dominant handicap standards - that of the Cruising Club of America which covered North and South Americas, and the standard of the Royal Ocean Racing Club for Europe and the Antipodes. The combined ruleset, the International Offshore Rule or IOR, was initially successful. The ORC developed International Measurement System (IMS) in the early 1990s and it was widely used to the early 2000s. This made use of a Velocity prediction program or VPP. While still maintained, the IMS has been largely superseded by the Offshore Racing Congress Rule in its Internatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Velocity Prediction Program
A velocity prediction program (VPP) is a computer program which solves for the performance of a sailing yacht in various wind conditions by balancing hull and sail forces. VPPs are used by yacht designers, boat builders, model testers, sailors, sailmakers, also America's Cup teams, to predict the performance of a sailboat before it has been built or prior to major modifications. Background The first VPP was developed at the Massachusetts Institute of Technology during the early 1970s when Commodore H. Irving Pratt funded research to predict the performance ''"of a sailing yacht, given knowledge of its hull, rig and sailplan geometry"''. Methodology VPPs are iterative programs which require educated guesses of initial parameters to begin operating. Generally VPPs are composed of two mechanisms, a ''boat model'' and a ''solution algorithm''. Initial guesses of parameters including boat speed (Vs), heel angle (Φ), number of reefs and sail flatness are input into the ''bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IRC (Sailing)
IRC is a system of handicapping sailboats and yachts for the purpose of racing. It is managed by the Royal Ocean Racing Club (RORC) in the United Kingdom through their dedicated Rating Office, and the Union Nationale pour la Course au Large (UNCL) in France. IRC stands for International Rating Certificate. Originally, “IR” was an abbreviation for International Rule. However, since the Rule at that stage was not recognized under International Rule (sailing), that name was not permitted. So RORC simply decided to keep the initials as the name, and the name remained simply IRC until 2016. The IRC rule is not published, meaning the only bodies capable of calculating an IRC rating are the RORC Rating Office and UNCL Centre de Calcul in Paris (they are joint owners of the Rule). This prevents designers from attempting to design 'to the rule'. The earlier IOR was published, and often amended, resulting in widespread criticism for several reasons. Firstly, as the rule effectively d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Offshore Racing Congress Rule
The Offshore Racing Congress Rule is a system of handicapping sailboats for the purpose of racing. It is managed by the Offshore Racing Congress (ORC) and is usually referred to in the sailing community simply as "ORC". ORC is an enhanced version of the earlier IMS handicapping system that was used globally from the early 1990s to the early 2000s. Synopsis The ORC rule uses essentially the same concepts as the earlier IMS system but with a much more sophisticated velocity prediction program performing the handicapping calculations than was available in the IMS era. This improved program is designed to eliminate the problems that led to IMS falling out of favour with yacht clubs in the early 2000s. IMS is (as of 2008) gaining support among the premium ocean racing clubs around the world as it is an open system, where all the details of the handicapping formula are available to designers and boat owners. This allows a greater degree of certainty when designing boats than closed, sec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |