Yeoman & Kinsman Association

Measurement Rules

The Measurement Rules have been moved to the member's area of the website. You can access the area from the menu on the left and you will require your user id and password.

For the convenience of sail makers and measurers the sail measurement rules are below.

17.0 Sails

17.1 The following sails are permitted, standard mainsail, high aspect genoa or standard genoa or jib, spinnaker (only one shall be carried in a race).

17.2 Sails shall be made and measured in accordance with the R.Y.A/I.S.A.F. Sail measurement instructions except where varied herein. The mainsail, genoa, jib and spinnaker shall be of woven polyester material having the same fibre throughout. Unwoven windows are permitted in both the mainsail and genoa. The transparent material of such windows shall not exceed 0.3m sq per sail. Windows shall not be placed closer to the luff, leach or foot than 150mm.

17.3 Sails may be made by any Sailmaker, the mainsail, jib and genoa shall be white, except that coloured draft stripes are permitted. Spinnaker to own choice.

17.4 The sail numbers, letters and class emblem shall be placed as laid down in the I.S.A.F. yacht Racing Rules. The emblem shall not be less than 565mm high or 310mm wide. Numbers and letters shall be of the following minimum dimensions:-

Height 300mm; width 95mm (except No.1) thickness 50mm. Minimum space between adjoining figures 60mm. All Yeoman sail numbers will be black with exception of numbers on the spinnaker when white will be accepted should black be insufficiently visible on the coloured background. The Yeoman and Kinsman insignia shall comply to the pattern of the Designer. The Yeoman insignia will be black and the Kinsman insignia and sail number will be red.

17.5 Mainsail

17.5.1 No part of the sail or headboard shall extend beyond the inner edge of the prescribed mast bands 'A' and 'C' and the boom band.

17.5.2 The length of the leech shall not exceed 7350mm (straight line measurement).

17.5.3 The mainsail shall have three battens of any material which shall divide the leech, the aft edge of the sail into four (equal) parts (+/-50mm). The outside length of the batten pockets shall not exceed; Top 765mm, middle 915mm, bottom 915mm. The inside width of the batten pockets shall not exceed 50mm.

17.5.4 The distance between the head point and the aft head point shall not exceed 115mm measured at right angles to the luff.

17.5.5 The distance from the 1/4, 1/2 and 3/4 leech points to the nearest point of the luff, including the bolt rope, shall not exceed 2155mm, 1600mm and 920mm respectively. Any hollows in the leech shall be bridged by straight lines. The 1/2 leech point shall be determined by folding the sail with the head point even with the clew point. The 1/4 and 3/4 leech points shall be determined by folding the clew and head points to the half leech point.

17.5.6 One set of reef points or cringles for slab reefing may be fitted. One on a line 1066mm up the luff and the other 1091mm up the leech.

17.5.7 For a reduced sail, there is no restriction on the position of the battens, provided the luff measurers no more than 5970mm, the leech measures no more than 6200mm and the foot measures no more than 2360mm. The distance between the head point and the aft head point shall not exceed 115mm measured at right angles to the luff.

17.6 High Aspect Genoa

17.6.1 The 'triangulation' method of measurement shall be used if the width of the sail at the head exceeds 30mm.

17.6.2 The length of the luff shall not exceed 6967mm.

17.6.3 The length of the leech shall not exceed 6425mm.

17.6.4 The length of the foot shall not exceed 2950mm.

17.6.5 The measurement from the head to the mid point of the foot (determined by placing the clew point above the tack point) shall not exceed 6665mm.

17.6.6 Battens are prohibited.

17.7 Standard Genoa

17.7.1 The 'triangulation' method of measurement shall be used if the width of the sail at the head exceeds 30mm.

17.7.2 The length of the luff shall not exceed 6325mm.

17.7.3 The length of the leech shall not exceed 5740mm.

17.7.4 The length of the foot shall not exceed 3355mm.

17.7.5 The measurement from the head to the mid point of the foot (determined by placing the clew point above the tack point) shall not exceed 5950mm.

17.7.6 Battens are prohibited.

17.8 Jib

17.8.1 The 'triangulation' method of measurement shall be used if the width of the sail at the head exceeds 30mm.

17.8.2 The length of the luff shall not exceed 6325mm.

17.8.3 The length of the leech shall not exceed 5820mm.

17.8.4 The length of the foot shall not exceed 2290mm.

17.8.5 The measurement from the head to the mid point of the foot (determined by placing the clew point above the tack point) shall not exceed 6050mm.

17.8.6 Battens are prohibited.

17.9 Spinnaker

17.9.1 The spinnaker shall be a symmetrical, three cornered sail. No headboard, battens or other stiffening device other than normal woven reinforcing is permitted.

17.9.2 The sail shall be measured folded along its centre line with the leeches together.

17.9.3 The length of the leeches shall be a maximum 6400mm measured along the edge of the sail from the head point to the clew point.

17.9.4 The half width measurement of the foot shall not exceed 2250mm measured around the edge of the sail.

17.9.5 The half width measurement at half height shall be a maximum of 2288mm and a minimum of 85% of the sails half width foot measurement. The measurement shall be taken between points on the leech and the centre fold midway between the head and the foot.

17.9.6 The length of the centre fold shall be taken as the distance between the head and the mid point of the foot, measured around the fold of the sail and shall be a maximum of 7300mm.