Dabchick Class Association


Class Rules (Last revised August 1998)

  1. The object of these rules is to establish a class of boat which is one-design in all matters which affect the basic speed. The rules shall be interpreted in this spirit. All boats shall be built to conform with the class rules.
  2. Builders shall not attempt to get around the spirit or the letter of these rules. The rules are complementary to the measurement form. In the event of any discrepancy between the rules and the measurement form, the matter shall be referred to the DASA Technical Committee for a ruling. In addition any items found by the measurer to be not specifically sanctioned by these rules shall also be referred for a ruling.
  3. It is the responsibility of the owner to see that the boat is properly measured and to see that it thereafter always remains in class even after alterations, additions or rebuilding have been carried out.
  4. Since it is unlikely that these rules can cover in detail every possible eventuality, builders are strongly advised to clear doubtful points with DASA Technical Committee before starting construction, to avoid the possibility of boats being subsequently outclassed.
  5. Measurers shall be appointed by SAS.
  6. Boats shall be complete in every respect with all necessary gear when presented for measurement, except that sails may be measured separately.
  7. The measurer shall complete the measurement schedule by filling in the blank spaces.

    The form shall be signed by the measurer and sent to DASA c/o SAYRA. Subject to the approval of the Technical Committee, SAYRA shall be requested to issue a measurement certificate.

    This certificate or photostat copy, shall be taken to all official Dabchick Regattas and is to be produced upon official demand. If the boat does not measure correctly, no certificate shall be issued. If it is impossible for an error to be corrected then the forms shall be submitted to the Technical Committee for its ruling. Owners shall endeavour to have the boat corrected and re-measured before submission of the form.

  8. New owners should satisfy themselves that they are buying a fully certified boat. A buyer of a second-hand boat shall take over the responsibility of keeping the boat in class and he must immediately inform DASA of his new ownership. The certificate does not become valid for the new owner until transferred by SAYRA.

  9. The boat's official number shall be permanently carved into the transom in figures not less than 20 mm high. After it has passed the measurement, each sail shall be stamped, signed and dated legibly by the measurer near the head of the sail.
  10. No boat is permitted to race in the class unless it has a valid measurement certificate.

  11. Only the owner of the boat, the measurer and the measurer's assistants may be present during measuring.
  12. A measurer shall not measure a boat built by himself, if he is the owner, or if he is in some way an interested party.
  13. Only members of DASA may race a Dabchick.
  14. Regardless of age, the helmsman shall have the option to race either one or two-up, providing always that the number of crew on board at the first race in a series shall not be changed during that series.
  15. Approved life jackets shall be worn when racing.
  16. No means of supporting the crew outboard, other than toestraps, are permitted.
  17. The mainsail shall be set between the coloured bands on the mast and boom when racing.


  18. Hulls shall only be constructed of wood and/or glass reinforced plastic No carbon fibre or kevlar materials may be used.
  19. Hulls shall follow the general arrangement shown in the plans except where added to or varied by these rules.
  20. All hull measurements are exclusive of any rubbing strakes.
  21. A general tolerance of +- 15 mm is allowed for all measurements unless otherwise stated.
  22. a} Overall length from transom to outside of bow - 3607 mm

    b) length from transom to centre of jib attachment - 3457 mm

    c) The length of the jib attachment fitting 40 mm maximum

    d) length from transom to centre of mast step - 2697 mm

    e) length of mast step - 150 mm. maximum

    f) The deck along-the centre line shall be straight from bow to transom.

  23. Beam Measurements

    a) at transom 641 mm
    b) 710 mm from transom 895 mm
    c) 1625 mm from transom 1100 mm
    d) 2235 mm from transom 1150 mm
    e) 2850 mm from transom 1073 mm
    f) 3300 mm from transom 915 mm

  24. Position of centreboard case - distance from transom

    a) to aft end of case 1651 mm

    b) to forward end of case 2210 mm

  25. Width of centreboard case 26 mm maximum.

  26. a) Perimeter of one half of bow, measured from centre line along outer edge of a deck to a point 3300 mm from transom - 635 mm maximum.

    b) Vertical height of bow measured in centre line - 50 mm maximum.

  27. Depth of hull at middle of centreboard case 267 mm.

  28. Any rubbing strake or deck overhang shall not exceed the following measurements - vertically 15 mm and horizontally from hull 30 mm.

  29. At transom

    a) Depth of transom centre excluding skeg 114 mm

    b} Depth of transom sides 64 mm

    c) Skeg, if fitted, maximum length, depth below keel 30Omm, 30 mm

  30. Hull upside down

    Distance from transom (mm) 710 1625 2235 2850 3300
    Depth from keel to gunwale (mm) 184 235 242 203 118
    Depth from keel to chine (mm) 95 133 140 114 73

  31. The hull shall be weighed with permanently attached fittings, toestraps and hatch covers included, cordage excluded. The minimum hull mass shall be 38,6 kg.
  32. If the hull weighs less than 38,6 kg, correctors shall be attached, adjacent to the mast step either above or below deck. The mass of the correctors shall not exceed 5 kg.

  33. Daggerboard - shall float and be rectangular in shape except that the corners may be rounded.

    a) Width - 279 mm maximum.

    b) Thickness 100 mm from any edge - 16 mm minimum.

    c) Depth below keel when fully lowered perpendicular to deck centre line - 647 mm maximum.

    d) The daggerboard shall be attached to the hull by a lanyard.

  34. Rudder - the rudder may be lifting or fixed and may be constructed of aluminium or wood. It may be covered with glass reinforced plastic.

  35. Thickness below the waterline 50 mm from any edge of the rudder. 3 mm minimum for aluminium 9 mm minimum for wood

  36. a) Rudder depth below bottom of transom - 410 mm maximum.

    b) Rudder width - 203 mm maximum.

  37. There shall be a fitting to prevent the rudder falling off if the boat is upside down.

  38. a) Mast and boom-the spars may be made of any materials except carbon fibre or kevlar.
  39. b) The mast rake shall not be altered during a race.

    c) Permanently bent spars are prohibited.

    d) Rotating masts are optional.

  40. Spars, excluding fittings, must be able to pass through a tube of 78 mm inside diameter, 300 mm long. ( For the purpose of this rule - a sail track which is not an integral part of the spar, i.e. it is for example riveted on, and which does not project more than 25 mm above the mating surface, will be considered to be a fitting.)

  41. Bands of contrasting colour to the spar, minimum 15 mm wide, shall be painted round the spar as follows :
  42. a) Mast

    from deck to top edge of lower band measured perpendicular to deck centre line - 762 mm maximum.

    from lower band top edge to upper band lower edge - 3480 mm maximum.

    b) Boom

    from aft face of mast excluding sail track to forward edge of band - 2159 mm maximum.

  43. Miscellaneous items: Breakwaters are optional.

  44. Transom holes are optional. The maximum number in the transom is two, maximum diameter 30 mm.

  45. a) Mainsheet travellers are optional.

    b) All fittings shall be attached to the external surfaces of the hull and may not be recessed in any way, except the following :

    (1) chain plates, which must be fitted within 10 mm from the external- side the hull.

    (2) forestay fitting may pass through the deck.

  46. Buoyancy

    a) Hatches are optional but if fitted shall be of a threaded type and the hull shall remain watertight under sailing conditions.

    b) Boats constructed of glass reinforced plastic shall have the same positive buoyancy as that of a wooden boat.

  47. Sails

    a) The sails shall be made of woven cloth.

    b) Headboard in the mainsail, excluding bolt ropes shall not exceed 115 mm measured square to the mast. No headboard is allowed in the jib.

    c) Only the jib may have a transparent window.

    d) The sails shall be measured as per the IYRU sail measurement instructions.

    e) Mylar may not be used in the cloth of which the sails are made.

  48. Mainsail

    The mainsail shall conform to the following measurements

    a) half height width excluding luff bolt rope - 1485 mm maximum.

    b) leech - 3810 mm maximum.

    c) battens: 3 in number, approximately equally spaced along the leech. Length of batten - 610 mm maximum.

    d) Dabchick insignia and number shall be not less than 200 x 140 x 30 mm.

    e) loose footed mainsails are not permitted.

    The numbers shall conform to the requirements of the IYRU Racing Rules.

  49. Jib

    The jib shall conform to the following measurements :

    a) luff and leech - 2667 mm maximum.

    b} Foot - 1473 mm maximum.

    c) Centre measurement - 2720 mm maximum. ( from highest point of sail on the luff to the lowest edge of the sail at the mid point of the foot. )

    d) Optional window, size - 1500 sq.cm maximum.

  50. A single track adjustable fairlead may be fitted on the port and starboard deck. No barber haulers are allowed.

  51. Sails and spars used in the first race of a series shall not be changed during the series. In the event of irreparable damage the written permission of the race committee shall be obtained before substitution.

  52. a) The Dabchick may be built by any professional builder.

    b) Professional builders shall be responsible for supplying boats complying with the class rules.

    c) The builder at his own expense shall arrange for the measurement of the hull/spars/sails supplied by him prior to the end user taking possession of the boat.