Kestrel Owners'

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Constitution &
Class Rules

Revised August 2016


1.1 Title. The full title of the Association shall be:

1.2 Aims & Objectives.

1.3 Membership.

1.4 Subscriptions.

1.5 Management.

  1. The affairs of the Association shall be managed by a Committee consisting of a Chairman, Honorary Secretary, Honorary Treasurer, and a minimum of two members, all of whom shall be elected at the AGM. and Technical Advisors who may be nominated by the Committee.
  2. If, by the death or resignation of any member of the Committee, a casual vacancy occurs, the Committee may co-opt, by a majority vote, any member of the Association willing to fill the vacancy and may repeat this process for each vacancy so occurring. Members co-opted to fill such vacancies shall be entitled to full voting rights and shall be eligible for re-election. Co-opted members must be either re-elected or replaced at the following AGM.
  3. The Committee may, at any time, invite any members or non-members to attend its meetings for any special purpose. Such persons shall not be entitled to vote.
    (d) At an Annual General Meeting or an Extraordinary general Meeting the Chairman shall have no vote except a casting vote in the event of a tie.
  4. The Honorary Secretary shall be responsible for the keeping of the Minutes of Committee and General Meetings, a register of members and other relevant records. He shall also be responsible for communicating the decisions of the Committee and to members, other interested individuals and organisations. The Honorary Treasurer shall have charge of the funds of the Association, making payments as authorised by the Committee. He shall keep a record of the Association’s financial affairs and shall produce a Balance Sheet (audited by an Auditor appointed by the Committee) at the AGM. The Association’s financial year shall end on the 30th September in each year. The Association encourages the formation of overseas branches of the Association.

1.6 Meetings.

  1. The AGM of the Association shall be held concurrently with, and at the venue of, the National Championship, on a day fixed by the Committee.
  2. Not less than 14 days notice, which shall include the agenda, shall be given of an AGM or an Extraordinary General Meeting and items for the agenda shall be submitted by members not less than 2 calendar months before the AGM.
  3. The Secretary shall call an Extraordinary General Meeting on the direction of the Committee or on receipt of a written request signed by at least 12 members of the Association stating the purpose for which the meeting is to be called. Such a meeting shall be held within 28 days of it being called. Only that business may be transacted for which the meeting was called.

1.7 Postal Ballots.

1.8 Alteration Of The Constitution.


2.1 Introduction.

  1. To define the Kestrel One Design, by establishing certain measurements.
  2. To maintain a high standard of construction, quality and strength at moderate cost by enforcing adherence to this definition.
  3. To control development and to encourage refinements that tend to improve standards of quality, strength or functional efficiency and performance while preventing modification that would tend to change the character of the Kestrel or increase cost.



3.1 Control of Construction and Protection of One Design.



3.2 Hull Measurements.

3.2.1 Hull Shape.

3.2.2Length: overall, excluding fittings.476313
3.2.3Beam: 2134 mm forward of the transom 170213
3.2.4Centreplate Slot:
(a) Outside transom to forward end 261625
(b) Outside transom to after end 130825
(c) Width13 1
(d) Outside transom to pivot 252713
(a) Length from stemhead to aft edge 76 off entreline. 171413
(b) From stemhead to projection of aft edge of gunwale (Mk 1/2 Kestrels only)223513
(a) Height above the skin, 152 off centre line. 43213
(b) Width 14610
(c) Distance, outside transom to aft edge 193013
3.2.7Mast Step: Height of upper surface above inside of skin. 31713
(Boat numbers below 138 do not need to comply with this rule).
Rules 3.2.2 to 3.2.7 are considered once in a lifetime measurement and are guaranteed by the builder and should not require re-measuring.

3.2.8 Keelband:

3.2.9 Hull Weight.

3.2.10 Class Number:

3.2.11 Mast

  1. The mast must conform to the official drawing on page 18, be of light alloy and may be either Proctor ‘D’, Proctor Cumulus or Super Spar M7 (or the equivalent in characteristics and strength, subject to the prior approval of the committee).
  2. It is essential that wherever the mast foot is actually placed, the shroud plates will be fixed to the skin of the hull at deck level not less than 305 mm aft of mast step.
  3. Mast bend fore and aft may be controlled by fixings at gooseneck level or below provided that sideways bend is not restricted other than by mast gate and spreaders.

3.2.12 Boom:

3.2.13 Centre-Plate:

  1. Shape and hole positions must conform to the full size templates.
  2. Material must be either galvanised steel or light alloy.
  3. The plate shall be made from a maximum metal thickness of 10 mm (excluding packing as in ‘f’
  4. below).
  5. Weight is not to exceed 28 kg nor be less than 10 kg (Boats built in 1963 and earlier may use a 7 kg alloy plate).
  6. Non compressible stops to a minimum of 25 mm in diameter must be fitted to the horn of the plate in the hole supplied .
  7. The centre-plate may be packed above the keelband to ensurea better fit in the centre-plate case.

3.2.14 Spinnaker Pole ( or Jib Stick) :

3.2.15 Buoyancy:

Flotation Test:

Dry Buoyancy test:

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4.0 Rules primarily for the control of racing performance.

4.1 Measurement Certificate:

4.2 Sails:

  1. Any one boat may have certified as eligible for racing three mainsails, three foresails and two spinnakers.
  2. All sails must be marked indelibly with the makers registered number and, in addition, the mainsail must bear the Class Insignia: a symbolic wing 635 mm in length on each side of the sail at an angle of 45 degrees to the mast, the thicker end downwards and forwards, together with the boats registered number according to ISAF requirements.
  3. The spinnaker shall also bear the boat’s registered number on the outside of the sail when being flown. Such identifying marks may be in a contrasting colour.
  4. When sails (mainsail and foresail) are permitted to contain a window, the foresail will now only contain one window, but the mainsail may have two.

4.2.1 Measurement:

4.2.2 Mainsail Dimensions :

Luffuncontrolled, except by limit bands.
Footuncontrolled, except by limit bands. No part of the foot may be allowed to fall below the bottom edge of the boom.
Leach6401 mm
Widthhalf height (including bolt rope) 1981 mm three quarter height (including bolt rope) 1245 mm
Headboardwidth 102 mm
Top batten maximum length1219 mm
Lower battens maximum length838 mm
  1. Measures overall less than 5334 mm in the luff and less than 2210 mm in the foot, or
  2. has a combined length round the bolt ropes of less than 7467 mm then the number of battens may be reduced to three, dividing the leach in four approximately equal parts. There is no requirement to measure leach length, half height and three quarter height width; however, the requirements must still be met relating to: Batten length and width; Sail material; boat number and class insignia; window and headboard.

4.2.3 Foresail Dimensions.

Luff4115 mm
Leach4064 mm
Foot2413 mm
Window: maximum area of186040 square mm
Maximum roach on leach102 mm
Maximum distance from head to mid point on foot 4013 mm with the foot following a fair curve through the point from tack to clew

Jib Dimensions:
Luff3810 mm
Leach3454 mm
Foot1600 mm
The jib sizes are recommendations rather than legal restrictions and a window is permitted. The genoa rules will be applied to all foresails.


4.2.4 Spinnaker:

4.2.5 Setting a spinnaker:

Height4572 mm
Width2896 mm
Foot2896 mm

Half height width not less than three quarters of foot width.

4.3 Rig.

4.3.1 Type:

  1. The fitting of the forestay is optional.
  2. There shall be no adjustment of the shrouds whilst racing.

4.3.2 Control of Sail Plan & Limit Bands:

  1. A band shall be located on the mast with its upper edge 1295 mm ? 13mm above the inner skin of the hull. On boats No 139 onwards in which the height of the mast step is standardised at 317 mm this band can be located 990 mm ? 13mm from the shoulder on the butt of the mast (datum point). The upper edge of the boom shall not be set below the level of the upper edge of this band whilst racing.
  2. A band shall be located near the head of the mast with its lower edge not more than 5791 mm above the upper edge of the band specified in (a) above. No part of the mainsail shall be hoisted above the lower edge of this band whilst racing.
  3. A band shall be located on the boom with its forward edge 2730 mm aft of the after edge of the luff groove when the boom is assembled on the gooseneck. No part of the foot of the sail shall be extended aft of the forward edge of this band whilst racing.
  4. The extended line of the forestay and the luff of the jib shall meet the mast not more than 3885 mm above band (a).
  5. The spinnaker halyard exit from the mast shall not be more than 4013 mm above band (a).

4.4 Prohibitions.

5.0 General Rules.

5.1 Champion’s Insignia:

5.2 Racing Crew:

  1. The Kestrel shall be raced by two or three persons including the helmsman, unless specified in Sailing Instructions.
  2. In races organised by and for the Kestrel Owners’ Association, only Full or Associate Members of the Association may take the helm, except for brief emergency reasons.

5.2.1 Substitution of Crew:

5.3 Rudder:

5.4 Class warning Signal:

5.5 Measurement Form and Measurement Certificate:

6.0 Class advertising for the year 2000 onwards:




6.4 Advertising on sails:


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