Hello
As man interested in aeronautics I have two easy question for sail designers when look at windsurfing sail at first:

1)Why sail has rake if upright sail has better lift over drag ratio?
*why dont move mast track back and design upright sail with larger foot,you can gain more speed at Luderitz channel.
*swept wing at subsonic speed ,significantly reduce wing efficiency


2)Why battens are not parallel to the water/airflow when sail is raked during planning?
*battens gives sail ideal airfoil profile so air must follow batten path,look at any hang glider,they all have battens parallel to the airflow/parallel to longitudinal axis,why this is not case at windsurfing sail?

Noah