There has been a great deal of discussion through the years on the issue of whether a loose footed main should be allowed. Proponents of the loose foot main prefer the ease of installation of the sail on the boom. The majority of opponents to the loose foot main are concerned with the potential for an unregulated foot dimension resulting in increased sail area.

In discussion with several of the Class’s sail makers, it is clear that the costs associated with fabrication of a loose foot main will not be any more than the current boltrope main. Likewise, it is clear that there is no compromise to the boom integrity with a loose foot main in use compared to the standard boltrope foot main. There are neither identifiable competitive advantages, nor disadvantages associated with use of a loose foot mainsail. Furthermore, after considering the typical dimensions of the foot shelf commonly found on the boltrope mains, it appears that the class can easily control the sail area with an easily measured foot roach dimension.

Therefore, I am recommending to the Executive Committee that the Class modify the Class Specifications, Section 3.5, Article V: Sails, 2.0 Mainsail, to allow the use of a loose foot main with appropriate changes to also control the foot roach. Attachment of the mainsail to the mast will remain the same for either type sail. Attachment to the boom for the boltrope foot main will remain as currently defined. Attachment to the boom for the loose foot main shall be by way of the existing tack pin and slug attached to the clew of the mainsail. Maximum Foot Roach shall be 4 inches.

1. General: San Juan 21's may carry mainsail, jib, genoa, and spinnaker, as shown in the sail plan and as herein specified when racing in Class Association races. Only two suits of working sails with genoa and spinnaker will be approved for use by a contestant in National Regattas.
2. Mainsail:
   1. The luff of the mainsail shall be attached to the mast and boom by arrangement of its boltrope (or slugs attached thereto) in the grooves of the spars. Loose-footed mains are prohibited allowed. The foot of the mainsail shall be attached to the boom by either its boltrope in the grooves of the spar, or if loose-footed, by the tack-pin at the tack and a slug at the clew.
   2. Luff and foot measurements shall be controlled by the band system.
   3. Sail measurements shall be made with sufficient tension to draw the cloth smooth and taut. The leech chord, measured from the aft corner of the headboard, shall not exceed 24 feet 6 inches. The girth, is measured at 90 degrees to the luff chord, at 6 feet 0 inches, and 12 feet 0 inches down from the head. At 6 feet 0 inches down from the head, the girth will not exceed 3 feet 11 inches. At 12 feet 0 inches down from the head, the girth will not exceed 6 feet 3 inches. All measurements will include the boltrope. Maximum foot roach is 4 inches.
   4. Battens shall divide the leech chord into equal sections with 2-inch tolerance to avoid seams on all but the top batten. The aft top corner of the top batten pocket will be a minimum of 56 inches from the aft corner of the headboard. Maximum batten lengths are: upper - 24 inches, two middle and lower - 36 inches.
   5. Hollows in leech between battens are not to exceed 3/4 inches in roach.
   6. Headboards shall be triangular, with the upper side of the triangle not exceeding 4 inches in length.
   7. The mainsail shall be made of 3.5 oz. or heavier woven material. Mylar or other film construction is prohibited.
   8. A Cunningham or sail control grommet is permitted.
   9. A reefing zipper on the mainsail is not permitted to be used while racing. Roller, slab or jiffy reefing is allowed.
   10. Windows in the mainsail are permitted.