Classic Moth Boat Association

Classic Moth Boats

Classic Moth Boats are a class of small fast singlehanded racing sailboats that originated in the US in 1929 by Joel Van Sant in Elizabeth City, NC. The Classic Moth is a monohull development class using a modified version of the International Moth rule in effect pre 1969. With an eleven foot over-all length, a maximum beam of 60 inches, a minimum hull weight of 75 pounds, 72 Sq Ft sail area, and very few other restrictions a Classic Moth can be a skiff, pram, scow, skinny tube, dinghy, or any combination thereof. The Classic Moth Boat is an ideal class for amateur designers builders and tinkerers, and can be easily built from inexpensive materials.

If you wake up in the middle of the night with a novel idea for hull shape, you can leap out of bed, race down to your garage, build it and then find out at the next regatta if your idea is hot or not. Freedom of design sets Moths apart from the clorox bottle (one-design) crowd. Instead of the one design controlling who sails successfully, we design and build Classic Moths that fit our size, ability, taste, skills, artistic expression, and pocketbook.

To broaden the appeal to race all types of Classic Moths, we have created three divisons within the class. At major regattas, all Classic Moths race together but are scored in three different divisions; a Gen 2 division for full on narrow waterline, low wetted surface designs, a Gen 1 division for more stable, higher wetted surface designs, and a Vintage division for restored Moths built before 1950.

Presently, Classic Mothboats race in many locations up and down the east coast of the United States. Regattas are currently held in Brigantine, NJ; Portsmouth, VA; Chestertown, MD; Cooper River, PA; Augusta, GA; Norfolk, VA; Elizabeth City, NC; Charleston, SC., and St. Petersburg, FL. Please refer to the regatta schedule on this site for dates and contact information.

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Measurement Rules

Details
  1. Classic Moths shall conform to the Equipment Rules of Sailing (ERS) as published by the International Sailing Federation (ISAF), except as modified by these rules. Definitions and figures from the ERS shall be used to interpret these rules as applicable. 
  2. Basic Definition: A Classic Moth is a monohull boat with one sail, mast, boom, rudder, and either one centerboard or one daggerboard, as further defined by these rules. 
  3. Hull:
    1. Hull length shall not exceed 11 feet exclusive of protuberances such as fittings or deck joining flanges.
    2. Hull beam shall not exceed 60 inches overall.
    3. Hull weight shall be a minimum of 75 pounds.
    4. Structural parts shall not be unreasonably increased in any area with the sole intent of improving the weight distribution of the hull.
    5. No ballast is permitted.
    6. No hollows or concavities that exceed 1 inch in depth shall exist below the sheerline and aft of the leading edge of the centerboard or daggerboard.
    7. Hiking boards, trapezes, trampolines, outriggers, or other devices to assist in hiking with the exception of foot straps are not permitted.
    8. The hull shall have sufficient flotation to allow bailing it out, if swamped.
    9. Hydrofoils are not permitted.
  4. Spars:
    1. Limit Marks: The Limit Marks shall have a minimum width of ¾ inch.
    2. Mast:
      1. The distance from the lower point to the upper point shall not exceed 15 feet.
      2. The mast section shall not exceed 3 and ½ inches in any direction.
      3. The distance from the upper point to the top of the mast shall not exceed 6 inches.
    3. Boom:
      1. The outer point distance shall not exceed 9 feet.
      2. The boom section shall not exceed 3 inches in any direction.
  5. Sail (Definitions and Diagrams of the ISAF ERS apply):
    1. Sail material is not limited.
    2. The leech length shall not exceed 17 feet 5 and 29/32 inches.
    3. The half width shall not exceed 66 inches.
    4. The three quarters width shall not exceed 36 inches.
    5. The Aft Head Point shall be within 1 and 5/8 inches of the Luff or Luff Extension.
    6. All sails will display the Moth Emblem consisting of a 12 inch outside diameter blue circle with inscribed red M. Circle and M width shall be 1 and ½ inches.
    7. All sails will display numbers as approved by the CMBA or local authority. Boat registration numbers of the IMCA will be honored, if known.
    8. If the sail is loose footed, the foot round shall not exceed 3 inches. If the sail is attached to the the boom along the foot, the attachment(s) shall ensure that no part of the foot shall drape more than 3 inches below the attachment(s).

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