IRC Wide Headfoils - Rig Factor

IRC Wide Headfoils - Rig Factor


WIDE HEADFOILS – RIG FACTOR

Extra wide headfoils are considered to be a way to gain ‘free’ un-measured sail area, and are therefore covered by IRC rule 21.2.2 (red highlight added): 

21.2.2   RF may be increased for: fractional, racing and lightweight rigs, high aspect ratio and efficient plan forms, wing and double luff sails, specialised sail stiffening, exotic sailcloth materials, large headboards/cranes, permanently bent or highly controllable spars, hi-tech rigging, exotic rig materials, advanced winch and deck gear arrangements, flush/efficient deck design, and any other feature which increases sailing efficiency that is not already rated through the rated dimensions. 

 
An example is a boat fitted with a partially fabric foil with a luff groove on the trailing edge, measuring a total of 75mm compared to a sistership’s standard 40mm foil. 
 
The IRC Technical Committee has agreed the following: 

Measurers and owners shall report the maximum dimension in millimetres of any luff groove device that is greater than 1 mm per 0.0033 x LH*. The maximum dimension is measured at right angles to its longitudinal axis.  *As a simple and practical first check only this approximately equates to 1 mm per 1 ft LH. 

IRC Technical Committee  20 April 2020 
 

You Can Receive Our Round Up News Email

OFFICIAL NOTICES

Any changes to syllabus, law or influences that effect training centres, clubs and classes
will be posted as OFFICIAL Notices or TRAINING NOTICES and listed here.