The J Class

J Class yachts were originally built to the specifications of the Universal Rule. The J Class really represents the golden age of racing for the America’s Cup in the 1930s when this Universal Rule was used as the determining measurement system.

About the Class

Designers had to produce a J Class yacht which had a rating of between 65 and 76 feet. That was not the length of the boats but a product of the limiting factors of the rule’s equation. Any of the determining factors such as length, displacement or sail area could be changed but such changes required proportionate change in other factors to compensate. This allowed them to be raced on a level basis. Stability was not taken into account. Limits were set on measurements for waterline length, draft, freeboard and so on.

The three original surviving Js - Velsheda, Shamrock and Endeavour - have been refitted for worldwide cruising and racing. Their displacements have increased and the yachts no longer rate as a J under the Universal Rule definition, with the exception of Shamrock V, which was the smallest of the Js.  

In total nine J Class yachts are active now with six replicas having been built since 2003; Ranger, Rainbow, Hanuman, Lionheart, Topaz and Svea.

The J Class Association

The J Class Association (JCA) was founded to protect the interests of the Class, present and future. Among its responsibilities it monitors and agrees the veracity of designs to which new replica boats can be built to, the build materials and specifications, which since Hanuman and Lionheart have included aluminium alloy.

It’s objective is to keep the J Class fleet and races alive and to encourage new build yachts (replica builds from original plans) to join the Class. The intent is to race the surviving Js, new existing Js, and potential new replica Js together in such a manner that has a fair handicap, to ensure that.

The racing will be both sporting and safe, respecting the historic background of the Class
The racing will be with boats potentially ‘close’ together
The differences in speed potential will be handicapped in such a way that the best sailed boat should win
The rules will allow the boats to sail at their best
The racing will be competitive

The Rules

The Rules are kept as short and simple as possible, in order to meet the objectives.  The Rules are written in the proper gentleman’s spirit, not to be bypassed to gain advantage, which is not in the spirit of the Class.

The original late 20th Century refits of the three surviving Js were used to help respect the tradition and guide the structure of these rules.

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