The International Radio Sailing Association (IRSA) formerly the ISAF Radio Sailing Division is an affiliate member of World Sailing that sanctions radio-controlled sailing competitions. It is authorised by WS to conduct up to three official World Championships each year.
Four classes of radio sailing boat are designated as IRSA classes, as follows from the smallest to largest:
The IOM class rules specify a monohull of maximum length 1000 mm, with maximum draught 420 mm. There is a minimum weight of 4000 g, which makes homebuilding of competitive boats possible. The IOM has three one-design rigs. To keep costs down, hull materials are restricted to either wood or glassfiber, while masts and booms are restricted to either aluminium or wood.
A Marblehead has a maximum length of 1290 mm and a maximum draught of ca 700 mm, but no minimum displacement. Up to six rigs are allowed.
At the I.M.Y.R.U. General Meeting at Dunkerque in 1982, it was resolved to adopt the IYRR and IYRU Measurement Instructions and to follow the IYRU Constitution and Regulations as closely as possible. For the next eight years a lot of very hard work was done by the I.M.Y.R.U., particularly by its then chairman, Norman Hatfield, to get Model Yachting accepted into membership of the full-size governing body, the International Yacht Racing Union (IYRU). This work culminated on 1 May 1990 when the I.M.Y.R.U. became the Model Yacht Racing Division of the IYRU (IYRU - MYRD). In its turn, in August 1996, the IYRU changed its name to the International Sailing Federation (ISAF) and IYRU-MYRD became the ISAF Radio Sailing Division (RSD). In 2009 the Division changed its name to International Radio Sailing Association to make it clear that it was an independent body and not a part of ISAF, now World Sailing. The two organisations have close links with World Sailing officially recognising its World Championships and using the IRSA to advise on developments of Appendix E of the Racing Rules of Sailing.
World Sailing (WS) is the world governing body for the sport of sailing recognized by the International Olympic Committee and the International Paralympic Committee (IPC).
The Star is a 6.9 metres (23 ft) one-design racing keelboat for two people designed by Francis Sweisguth in 1910. The Star was an Olympic keelboat class from 1932 through to 2012, the last year keelboats appeared at the Summer Olympics.
Sailing/Yachting is an Olympic sport starting from the Games of the 1st Olympiad. With the exception of the 1904 and the canceled 1916 Summer Olympics, sailing has always been included on the Olympic schedule. The Sailing program of 1908 was open for a total of five sailing classes (disciplines), but actually only four Sailing events were contested. The planned venue of all races, named matches, was Ryde, Isle of Wight.
The International 505 is a One-Design high-performance two-person monohull planing sailing dinghy, with spinnaker, utilising a trapeze for the crew.
The 12 Metre class is a rating class for racing sailboats that are designed to the International rule. It enables fair competition between boats that rate in the class whilst retaining the freedom to experiment with the details of their designs. The designation "12 Metre" does not refer to any single measurement on the boat, and is not referencing the vessels overall length, rather, measures the sum of the components directed by the formula which governs design and construction parameters. Typically 12 Metre class boats range from 65 to 75 feet in length overall; they are most often sloop-rigged, with masts roughly 85 feet tall.
The Universal Rule determined a yacht's eligibility to race in the America's Cup from 1914 to 1937 and for this the J-class was chosen. Boats built according to the rule reached their peak in the large J-class yachts. This Rating Rule is intended to calculate a rating for yachts, which can then be used to calculate its Time Correction Factor (T.C.F.) in order to have disparate yachts racing against each other. The first boat said to be built under the universal rule was Herreshoff's Doris built in 1905.
Model yachting is the pastime of building and racing model yachts. It has always been customary for ship-builders to make a miniature model of the vessel under construction, which is in every respect a copy of the original on a small scale, whether steamship or sailing ship. There are fine collections to be seen at both general interest museums such as the Victoria and Albert Museum in London and at many specialized maritime museums worldwide. Many of these models are of exquisite workmanship, every rope, pulley or portion of the engine being faithfully reproduced. In the case of sailing yachts, these models were often pitted against each other on small bodies of water, and hence arose the modern pastime. It was soon seen that elaborate fittings and complicated rigging were a detriment to rapid handling, and that, on account of the comparatively stronger winds in which models were sailed, they needed a greater draught. For these reasons modern model yachts, which usually have fin keels, are of about 15% or 20% deeper draught than full-sized vessels, while rigging and fittings have been reduced to absolute simplicity. This applies to models built for racing and not to elaborate copies of steamers and ships, made only for show or for " toy cruising."
The International rule, also known as the Metre rule, was created for the measuring and rating of yachts to allow different designs of yacht to race together under a handicap system. Prior to the ratification of the International rule in 1907, countries raced yachts under their own national rules and international competition was always subject to various forms of subjective handicapping.
The A-Class Catamaran, often abbreviated to A-Cat, is a development class sailing catamaran for singlehanded racing.
A radio-controlled boat is a boat or ship model controlled remotely with radio control equipment.
The Moth is a small development class of sailing dinghy. Originally a small, fast home-built sailing boat designed to plane, since 2000 it has become an expensive and largely commercially produced boat designed to hydroplane on foils though many are still built at home, typically at much lower cost.
Sailing/Yachting is an Olympic sport starting from the Games of the 1st Olympiad. With the exception of 1904 and the canceled 1916 Summer Olympics, sailing has always been included on the Olympic schedule. The Sailing program of 1912 consisted of a total of four sailing classes (disciplines). For each class two races were scheduled from 19 July 1912 to 22 July 1912 off the coast of Nynäshamn at the Baltic Sea.
Skerry cruisers are yachts, usually wooden, which are constructed according to the Square metre rule. Originating from Sweden, they were historically most popular in the Baltic Sea, though some classes also saw popularity in other European countries and USA. Skerry cruisers are construction classes, meaning that though the boats are not identical with each other, they are all built according to same formula, making them broadly comparable in size and performance. Most skerry cruisers are slender boats, with low freeboards and tall rigs.
The International One Design is a class of sail boat developed in 1936 for yacht racing. It is a 33-foot open-cockpit day sailer used for day racing, rather than for overnight or ocean races. Popularised prior to the Second World War, the International One Design class is considered a classic one today.
The RS Tera is a one-man monohull dinghy in the RS Sailing range of sailing boats. It is recognised by the International Sailing Federation (ISAF) as an international class, and is a popular boat for beginners and for children to race.
The International One Metre (IOM) is a class of Radio Sailing Boat used for racing under the World Sailing - Racing Rules of Sailing. It is a measurement-controlled box rule originally created by the ISAF-RSD (now the International Radio Sailing Association) in 1988 in an attempt to harmonise the various one metre rules created around the world. The IOM Class Rules specify a standardised sail plan and control of the other major performance dimensions (displacement, length, and draught) while allowing some freedom in hull design. The IOM is now the largest and arguably most competitive of all radio sailing classes.
The Transpac 52 (TP52) is a class of yacht used for competitive 52 Super Series yacht racing, and the Audi MedCup previously, besides the world championship of the class. The class is recognised by the International Sailing Federation which entitles the class to hold an Official World Championships.
The International Marblehead is a class of radio controlled sailing yacht used for competitive racing. It is a measurement controlled class administered by the International Radio Sailing Association.
The International Radio A Class (RA) is a class of radio controlled sailing yacht used for competitive racing. It is a measurement controlled classes administered by the International Radio Sailing Association. The class is a designated IRSA International class entitled to hold World Championships officially recognised by the International Sailing Federation. A RA class of boat is a classic looking boat similar to that of the full sized metre class. The RA class rules are loosely based on the 5.5 Metre. Modern boats use the latest carbon fibre technology with displacements typically between 13 – 16 kg, making them substantial yachts.
World championships in sailing are world championships organised or sanctioned by World Sailing. As a sport, sailing has the largest number of world championships due to the diversity of equipment and disciplines.