The 5O5 is a double-handed boat that incorporates a light weight, high performance hull design with a powerful sail plan and one trapeze. The boat is unique in that it has outstanding performance in all conditions. In light air it is quick and responsive, and in breeze it just goes faster. Planing begins in 10 knots of wind.

The Class Rules are One-Design, with the emphasis on controlling aspects that most directly affect boat speed. The sailplan and hull shape are tightly controlled, while the rigging layout, spars, and the foils are open. This allows the boat to be set up in many ways to suit the sailors; there are several distinct types of sail and layout combinations from the US, Australia and Europe. The result is that, at any Worlds, all the types will be used by the top 10 finishers, and usually by the top 5. Most US boats currently have adjustable shrouds, forestay, and mast ram, which allows rig tension, rake and bend to be changed while racing. There are many ways to rig the boat; it still takes the best sailors to win.

Hulls are built of either fibreglass/polyester or of epoxy resin/Kevlar and honeycomb compo site. Both types are equally competitive when new, but twelve year old epoxy composite boats can still win major championships.

The ideal sailing weight varies with the prevailing local conditions, but most successful racers have a combined weight near 340 lbs (155 kg). The boat is difficult to sail in breeze with under 310 lbs (140 kg) and few teams are over 400 lbs (180 kg). The current World Champions’ combined weight is 325 lbs (147 kg). Two boats with women skippers have won North American titles.

The 505 class was started in 1954 when the French Yachting Association decided to establish a new One-Design racing class. The boat was designed by John Westell of Britain. The rules for the hull shape and sailplan have not been changed.

The best way to get a feel for the boat is to take a ride. 505 sailors are friendly people who love to take people sailing. Active fleets abound around the world. Visit your Country Site for Contacts.

Make a call. Take a ride. Never go slow again.


The development of the Class began at the IYRU trials in l953, held at La Baule to find the “best possible two-man centreboarder”, an 18 footer “Coronet” showed clearly superior to all her competitors.That winter the Caneton Association, the most important small boat racing body in France, asked the designer of “Coronet”, John Westell (UK), if he could modify her to suit their rules. Reducing the overall length, lightening the hull and modifying it a little, together with cutting the sail area to 17,24 sq. mtrs., produced a new design which retained the good features of the larger craft. By a remarkable far-sighted decision members of the Caneton Association, at their A.G.M. in Paris in January 1954, voted unanimously to adopt the new class, even before the first boat had been built. The Five-0-Five was born!

With strong organisation already existing in France, the 505 started life on an International basis. The Class expanded rapidly and in November 1955 the IYRU accorded it official International status. Fleets developed in many parts of the world, most of these are still very active today, 18 Countries have active fleets.Although any material and type of construction may be used, current boats are now using carbon fibre and epoxy resins. The hull shape is strictly controlled with minimum weights both for the bare hull and the complete boat in sailing trim.

By January 2007 8930 boats had been registered.

International 505 Class Association / keyed by Ali Meller / updated by Jean-Baptiste DUPONT (Feb 2007)

Length: 16’6″ (5.05 meters)
Beam: 6’2″ (1.88 meters)
Weight: 280 lbs (127.4 kilos)
Sail Area: main (12,30 sq. m.)
jib (4,94 sq. m.)
main & jib 175 sq. ft.
Spinnaker up to (27 sq. m.) approximately (220 sq. ft. original size)
Crew: Two people, one trapeze

The 5o5, popularly known as the Five Oh, is a two person racing sailboat designed in 1954. So why is it still raced so much around the world and why is it becoming even more popular in recent years?

The answer to this question will depend on who you ask. And that is the fundamental reason for its success! No matter if you are an Olympian, World champion or an enthusiastic club racer there is fun and challenge to be had. There is something for everyone.

Unlike many of the Olympic classes where sailors come and go, the 505 class has an extraordinary accumulated level of expertise and talent. People you will find at major events are Olympians, past Olympians, Pro Sailors and World Champions. They have been competing for many years so there is a continuously accumulating knowledge bank of all aspects sail boat racing. This keeps raising the bar to ensure the Worlds best are never short of a challenge and newcomers have access to probably the most complete encyclopedia of sail boat racing anywhere.

The newer foiling classes are awesome. We should all try it. However with minimal training you can enjoy all that 505 racing has to offer without being lapped around the race course. The 505 rewards a more complete set of sailboat racing skills.

470s, 29er, 49ers, moths and even the foiling classes, do have relatively restrictive crew weight limitations to be competitive. The strength of the 505 is the power controls it has while racing. Vastly different weight crews, male and female, young and old, can compete against each other in all wind and sea conditions which most dinghies and skiffs cannot handle.