International Laser Class Association
LASER RADIAL SAIL CHANGES
The Laser Radial sail was originally designed for training and as an introduction to Laser sailing. Nobody, least of all Ian Bruce and Hans Fogh, instigators of the Laser Radial design, could have anticipated the current popularity and success of the Laser Radial as a serious international racing class. For some time there have been concerns over aspects of the Laser Radial sail design and construction in relation to the expectations of current owners, in particular the perceived short competitive life of the sail. Over the past 2 years, the World Council and the Laser builders have carried out an analysis of the Laser Radial sail and tested a number of different alternatives to improve the durability of the sail.
The design of the Laser Radial sail means that it works differently from the standard rig sail. Because of the panel design and cloth orientation the cunningham is not effective in pulling the draft forward and flattening the sail. The leech is closed and will not readily open in response to gusts. Very high cunningham loads have to be applied to the sail to effect adjustment to the sail shape, which accelerates the ageing process. The tight leech is exacerbated as the sail ages and the draft moves back.
Working with our sail makers, small changes in the sail were tested to try and achieve a more gust-responsive leech and better control of the draft without gaining or losing speed around the course. Small differences in the panel shapes in the back part of the sail produced a far more responsive sail, which was a lot easier to de-power. Most significantly, after ageing the leech continues to be as gust-responsive and the draft does not move back so quickly.
Larger corner patches were incorporated to eliminate some of the stress lines and give greater support to the relatively lightweight cloth in high stress areas. Modern straight batten pockets were also added to eliminate the problem of battens cutting through the batten pocket stitching. The sail area is unchanged.
The result of the programme is a sail that will de-power more easily with increased durability, without sacrificing performance around the course. The sail is more sensitive to vang and outhaul controls offwind, and smaller sailors will find the rig easier to manage. It is felt that sailors will easily adapt to this small difference in technique.
The World Council of the class have approved the introduction of the updated sail to come into effect from 1 August 2001. There will be no increase in prices attributable to the changes made to the sail.
Jeff Martin
Executive Secretary
21 September 2001