Olympic triangle

The Olympic triangle is a sailing course used in racing dinghies, particularly at major regattas like State, National and World Titles and was used at the Olympics. (Olympic sailing now uses quadrilateral courses)

The remainder of this article should be read in conjunction with Sailing Instructions for the specific regatta or the International Sailing Federation (ISAF) Race management page, the Racing Rules and particularly Appendix L.

The traditional Olympic triangle course consists of a lap (starting with a beat or work to windward from the starting line to the top, weather or windward mark, a first reaching leg to the wing mark (also known as the gybe mark), a second reaching leg from the wing mark to the bottom or leeward mark), a hot dog (a beat to the top mark with a square run back to the bottom mark), another lap and then a beat to the finish line, which may have one end at the top mark, or may be set beyond the top mark. When the finish line is set beyond the top mark, the sailing instructions need to specify whether the top mark remains a mark of the course on the final leg or whether it is to be ignored. There are generally 9 legs, 5 equal to the length of the windward leg (4 beats and a run) and 4 reaching legs (2 of each reaching leg), so once the leg lengths are known the total course length can be calculated. Roundings are generally to Port. Many sailing instructions only specify the length of the windward leg and the total course length, but see below on the use of the law of sines, trigonometry table and spreadsheets to calculate the angles and other leg lengths.

The angles of the triangle may not always be perfectly sharp, either, since it is a course.

Traditionally the configuration of the triangle is an equilateral triangle (3 equal sides and 3 equal angles of 60 degrees) with a ratio of the windward leg to a reaching leg being 1:1. In that case the course length for the 9 legs described above is 9 times the length of the windward leg. The angle at each point of the triangle is 60 degrees. The windward leg is generally aligned with the average wind direction.

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