10 Rater

 

This monohull development class, is recognized by the ISAF (formerly IYRY)'s Model Yacht Racing Division and is sanctioned by more than 20 individual Ten Rater Class Associations, which gives Ten Rater owners democratic control of the Class Rules.

The Ten Rater Class of model yachts is based on the length by sail area rule of 1887. Shortly after this rule was adopted for racing full size yachts, models began to use the rules as a basis for new classes. With a one inch to the foot, or 1/12th scale difference, the Ten Rater size of model yacht was a popular choice for its ease in transporting and reliable performance. The early days were all free sailing under progressively better devices for automatically controlling the rudder to hold the yachts to a straight course. While hull and sail design underwent similar development, the Class gradually gained a reputation for speed.

This tradition continues today under radio control, with modern Tens employing the most advanced design innovations and construction materials. The present rating Rule allows the greatest freedom to experiment with performance improving design and technology, within the size limitations of the Rule. This allows the Class to offer fair competition, between designers, builders and skippers. The Ten Rater Class is unique in its method of "rating" yachts. 

The only two parameters that matters are the waterline length of the hull and the total sail area. It would be more appropriate to say "rig" area as Tens are not limited to using only soft sails, but may use rigid wings, or a rotate, as is common on multihulls, but their contribution to propelling the yacht is not overlooked, as even the mast area is included in the yacht's rating. This approach is consistent with all aspects of the rig, with no design or material restrictions imposed nor any free areas given. The result of this unique rating method is the unparalleled efficiency with which Ten Raters extract power from the wind.

Below these powerful rigs, Ten Rater hulls are wide open to experimentation, except to the use of multihulls, tunnel hulls and off-centre or retractable appendages. Only the waterline length controls the size of the hull and that may vary in reverse proportion to the size of the rig. This allows Ten Raters to be highly specialized for exceptional performance in even the most extreme sailing ocean waves with strong gusts or local waters. 

Hull construction materials and techniques are often hi-tech and state-of-the-art, although modern wood construction may still be used by fine craftsmen, to produce competitive yachts. The greater emphasis is on design innovation, with a steady stream of new ideas coming from the drawing boards, or computers of both amateur and professional designers.