The following amendments to the Class Rules have been approved to be effective 1st June 2007.
is a one-design class.
Except where variations are specifically permitted, boats of this class shall be alike in: hull, deck and keel form, construction, weight and weight distribution; shape of rudder and sails.
All boats shall be built in accordance with these class rules and the plans. Deviations from the plans are permitted for spars, standing and running rigging, sheeting arrangements, rudder stock bearings, tiller and tiller extension, lifting eyes, fittings on deck, details of hatches and certain parts of the accommodation. These items shall comply with the rules.
All boats, in respect of hull, deck, keel and rudder form and construction and spars, shall comply with either the current class rules, or the corresponding rules applying to them at the time the first measurement certificate was issued. Any alterations or replacements shall comply with the rules current at the time the alterations or replacements are made.
Sails shall comply with the current rules.
Interpretations of these rules shall be made by the ISAF which in coming to its decision may consult the International H-Boat Class Association and the original plans.
|1.2|| These rules
are complementary to, and shall be read in conjunction with, the plans measurement form and measurement diagram.
|1.3|| In the event of discrepancy between
these rules, the measurement form and/or the plans, the matter shall be
referred to the ISAF.
authority for the class shall be the ISAF which shall co- operate with the
International H-Boat Association in all matters regarding these rules.
where there is no National Authority or the National Authority does not
wish to administer the class, its functions as stated in these rules shall
be carried out by the International H-Boat Association or its delegated
representative (National H-Boat Association).
|1.5||Neither the ISAF nor the International H-Boat Association accept any legal responsibility in respect of these rules and/or the plans, or any claims arising therefrom.|
|2.1.1||The official language of the class
is English and in the event of dispute over interpretation the English text
|2.1.2|| The word "shall" is
mandatory and the word "may" is permissive.
The H-Boat shall be built only by builders licensed to do so by the ISAF. Applications for licences shall be made to the International Yacht Racing Union which may issue a licence to a builder considered to have appropriate production facilities, knowledge and experience and to be able to fulfil such other conditions as the ISAF may deem necessary. A licensed builder shall be required to bind himself to comply with the class rules, plans, specifications and measurements.
|2.3|| International class FEE
An International Class Fee (ICF) shall be paid by the builder to the ISAF for each boat built. As evidence of payment of the International Class Fee the ISAF shall issue an official plaque.
|2.4||Registration and Measurement
|2.4.1||No boat is permitted to race unless
it has an valid measurement certificate.
|2.4.2||ISAF Plaque. The ISAF Plaque
shall be obtained by the builder before the boat leaves his yard. The plaque
will carry an ISAF serial number. The builder shall insert on the plaque
the builder's name, serial number of plug and mould. The plaque shall be
fixed to the hull in an permanent manner in the position indicated in rule
2.7.1 (see also plan no. A.3.4)
|2.4.3|| The certificate is obtained as
follows: The owner applies to his National Authority for a sail number giving
the ISAF Plaque number and the builder's name. The National Authority shall
issue a sail number only on receipt of these details as evidence that ICF
has been paid. Each country shall start its numbering from "one",
and each number shall be used once only. The boat shall be measured by an
official measurer recognised by the National Authority of the country in
which measurement takes place. The completed measurement form shall be supplied
to the owner of the boat. The owner shall send the completed measurement
form to his National Authority together with any registration fee that the
National Authority requires. On receipt of this the National Authority may
issue a Measurement Certificate to the owner.
|2.4.4|| Change of ownership invalidates
the Measurement Certificate but shall not necessitate remeasurement. The
owner may apply to his National Authority for a new certificate, returning
the old certificate with any re-registration fee that may be required and
stating the necessary particulars. The National Authority may then issue
a certificate to the new owner.
|2.4.5||It is the owner's responsibility
to ensure that his boat, spars, sails and equipment comply with the class
rules at all times.
|2.4.6||Changes and major repairs to the
boat, its spars, or equipment invalidate the certificate and require partial
remeasurement as the official measurer may determine.
|2.4.7||Notwithstanding anything in these
rules the ISAF or the National Authority shall have the power to withdraw
or to refuse to grant a certificate to any boat.
|2.5.1||Only a measurer officially recognised
by the builder's or the owner's National Authority shall measure a boat,
its spars, sails and equipment and sign the declaration on the measurement
|2.5.2|| Tolerances are given in these
rules and corresponding drawings to permit minor building errors or distortion
|2.5.3||The measurer may take supplementary
measurements in order to satisfy himself that the boat is in accordance
with the class rules. If the measurer considers that there is a departure
from the one design construction or these rules in any detail the National
Authority shall be informed. In such a case the National Authority shall
not issue a Measurement Certificate until the case has been investigated
and any necessary corrections have been made.
|2.5.4||All boats shall be measured using
the official templates supplied by the ISAF.
|2.5.5|| New or substantially altered
sails shall be measured by an official measurer who shall stamp affix a
licensed button or sign and date the sails near the tack.
|2.5.6||A measurer shall not measure a
boat, its spars or equipment owned or built by himself, or in which he is
an interested party or has a vested interest. Sails may be measured by sailmakers
licensed by their National Authority.
|2.6|| ISAF Measurement Instructions
Except where other methods of measurement are specifically indicated all measurements shall be carried out in accordance with the ISAF Measurement Instructions.
|2.7.1||The ISAF plaque shall be permanently
fixed to the bulkhead at the forward end of the starboard side cockpit locker
so that it can be clearly seen through the cockpit hatch.
|2.7.2||Sail numbers shall be carried on the mainsail and spinnaker in accordance with rule 18.104.22.168.|
CONSTRUCTION AND MEASUREMENT RULES
A master mould owned by the Finnish Yachting Association is available for obtaining plugs. This master mould shall be used unless permission not so to do has been given by ISAF.
In such a case a plug shall be made which shall be within tolerances which are one half of those for a completed boat and it shall be approved by the ISAF Chief Measurer before manufacture of moulds is commenced.
Before production is started
at the builder's premises the production moulds shall be checked and approved
by an official measurer recognised by the builder's National Authority.
|3.2.1||The hull, including the deck,
cabin, cockpit, hatches and inner hull moulding shall, unless otherwise
stated, be for glass reinforced plastic (grp) and shall be built according
to the plans and the laminate specification in Appendix 1.
|3.2.2||The deck moulding without fittings
or hatches shall not weigh less than 180kg. It shall be laminated to be
of uniform thickness.
|3.2.3||Hull measurements shall be taken
in accordance with, and shall be within the limits shown on the measurement
diagram and the measurement form.
the current rule as follows:
accommodation shown on the plan is the minimum that is required.
The design and location of the galley and locker may be changed subject to prior written approval being obtained from ISAF.
bulkhead with a hatch or a semi-bulkhead may be fitted forward of
station 9.5. The
minimum thickness shall be 6mm for plywood or 4mm for GRP.
|3.2.5||The forecastle hatch and a cabin
companionway hatch, hatches in the cockpit seats and a hatch for the aft
stowage space are compulsory.
|3.2.6||A well for an outboard motor may
be fitted in the aft stowage space.
|3.2.7||Lifting eyes may be permanently
fastened to two keel bolts. The total weight of the eyes shall not exceed
|3.3.1||The keel shall be of cast iron.
|3.3.2||The keel may be galvanised and/or
covered with any synthetic material.
|3.3.3||The weight of the keel shall be
725kg +/- 10kg including any coating.
|3.3.4||The keel shall be fastened to
the hull by seven 16mm diameter stainless steel or galvanised steel bolts.
|3.3.5||The shape of the keel including
any coating shall be controlled using the official templates.
|3.3.6||The aft end of the keel shall
have a square edge. The minimum width shall be 5mm, the maximum 8mm (see
||3.4.1||The rudder shall be of grp and
constructed in accordance with the plans and the specification.
|3.4.2||The rudder stock shall be of
25mm diameter solid stainless steel.
|3.4.3||A bearing of phenolic laminate
(such as Tufnol) or equivalent material shall be fitted to the rudder stock
trunk at deck level.
|3.4.4||A bearing of bronze or of stainless
steel shall be fitted to the lower part of the skeg.
|3.4.5||The rudder stock shall be in
the position indicated on the measurement diagram and shall be vertical.
|3.4.6||The tiller and tiller extension
are not controlled by these rules.
|3.4.7||The aft end of the rudder shall
have a square edge. The minimum width shall be 4mm (see plan A3.3).
|3.5.2|| Mast and Standing Rigging
|22.214.171.124|| The mast shall be stepped on
the cabin top on the centreline of the boat.
|126.96.36.199||The forward face of the mast
shall be 843mm +/- 40mm aft of station 8.
|188.8.131.52|| Two easily discernible marks,
each not less than 50mm x 20mm, shall be painted on the deck so that the
forward edge of the aft marks and the aft and the aft edge of the forward
mark indicate the permitted limits for the location of the forward face
of the mast.
The mast shall be an aluminium alloy extrusion. The section shall have the following dimensions:
fore and aft 125mm
+/- 10mm including the groove for the luff rope
The radius of the leading edge
shall not be less than 20mm and the point of maximum width of the section
shall not be less than 40mm from the forward or aft edge of the mast.
|184.108.40.206||The weight of the plain extrusion
shall not be less than 2.20kg/m.
The mast shall be straight
and of constant section except as permitted below:
Measurement bands, not less
than 10mm wide, which shall be clearly discernible while racing shall
be painted or otherwise permanently marked on the mast as follows:
The standing rigging shall
|The diameter of the backstay
shall be 3mm minimum. The diameter of the other standing rigging shall be
The length of the backstay wire is a minimum of 9500 mm including terminals.
The attachment point on the
mast of the upper shrouds shall not be more than 100mm from the lower
edge of band No 2.
The attachment point on the
mast of the lower shrouds shall be not less than 3320mm and not more than
3620mm above the upper edge of band No 1.
|220.127.116.11||The attachment point of the
forestay on the mast shall not be above the lower edge of band No 2 nor
more than 100mm below it.
|18.104.22.168||The backstay shall be attached
to the mast as indicated on the plan. A backstay tensioning system is permitted.
|22.214.171.124||The forestay shall intersect
the deck 1580mm +/- 5mm forward of station 8. If the jib is attached to furling
gear this measurement shall be taken to the line of the forward edge of
the jib in its most forward position.
|126.96.36.199||The main and lower shrouds shall
intersect the deck not more than 75mm inboard from the sheerline. The attachment
points shall each be not more than 3250mm nor less than 2850mm from the
intersection of the centreline of the forestay with the deck, measured radially.
|188.8.131.52||The bearing surface of the sheave
for the spinnaker halyard shall not be more than 100mm above the lower edge
of band No 2.
The spinnaker halyard shall not be supported more than 60mm forward of the forward face of the mast.
|184.108.40.206||Spreaders as shown on the plan
shall be fitted. The spreaders shall be not less than 700mm long measured
from the face of the mast to the bearing surface of the shroud. The centreline
of the attachment point of the spreaders shall be above and not more than
200mm from the attachment point of the lower shrouds.
|220.127.116.11||A stop shall be fitted to the
mast to prevent the line of upper edge of the boom from being below band
|18.104.22.168||The mast complete with all standing
and running rigging and supported at band No 1 shall not weigh less than
12kg when it is weighed at band No 3. For the purpose of this measurement
the halyards shall be fully hoisted and the standing rigging secured along
the mast. The ends of the rigging below band No 1 may rest on the ground.
|22.214.171.124||The main boom shall be an aluminium
extrusion of continuous section and shall have a continuous groove for a
boltrope. The dimensions shall be: depth 90mm +/- 15mm and width 75mm +/- 15mm. The weight of the extrusion shall not be less than 1.25kg/m. Tapered or
permanently bent booms are prohibited. However, a set due to distortion
not exceeding 30mm between inner edge of the measurement band and the inner
end of the boom is permitted.
|126.96.36.199||A measurement band, clearly
discernible while racing, shall be painted or otherwise permanently marked
on the boom with its inner edge not more than 3000mm from the mast measured
with the boom in its lowest position and perpendicular to the mast. The
measurement shall be taken from the line of the aft edge of the mast (shown
on the diagram of the mast section) projected downwards excluding any local
curvature due to the sail entry.
When attached to the mast the outer end of the spinnaker boom shall not be capable of extending more than 2415mm from the face of the mast. It shall be attached to the mast 950mm +/- 30mm above band No 1.
The sails shall be made and measured in accordance with Section G of the ISAF Equipment Rules 1997 - 2000, except where otherwise specified.
|188.8.131.52||The sails shall
be made of synthetic woven material. The cloth weight of the mainsail and
jib shall not be less than 200g/m², and of the spinnaker not less than
35g/m². Unwoven transparent panels with total area not exceeding 0.3m²
are permitted both in mainsail and jib. Windows shall be less
than 150mm from any edge of the sail.
|184.108.40.206||The class emblem,
national letter(s) and the yacht's sail number shall appear on both sides
of the mainsail. National letter(s) and sail-number(s) shall be on both
sides of the spinnaker, touching a horizontal centreline created by folding
the spinnaker in half horizontally at the half height of the leeches and
at the half of the vertical centre fold.
Letters and numbers shall be of the following minimum dimensions:
Width (excluding number one and letter I) 250mm
Space between adjacent letters and numbers 75mm
The class emblem shall be of a colour clearly discernible and contrasting with the sail or be of two colours in accordance with the plan and shall be of the following minimum dimensions:
Width 440mm overall
|220.127.116.11||Each sail measured
after 1st of January 2001 shall have permanently fixed near its tack an
official red IHA button. No sail shall accepted for its first measurement
without this button. The measurer shall sign next to the button. The button
shall be available from the IHA.
|18.104.22.168||The mainsail shall
not extend above the lower edge of band No 3 nor beyond the inner edge of
the band on the boom. The upper edge of the boom shall not be below the
upper edge of band No 1.
The length of the
leech shall not exceed 9190mm.
As an exception to the interpretation under 22.214.171.124 above the mainsail leech length shall
be taken as in the diagram and not in accordance with the ERS 1997-2000. That is the
shall be taken between the aft head point to the clew point.
The total width
of the mainsail (including the luff rope) between points on the luff and
leech at half and three quarter heights shall not exceed 1910mm and 1110mm
respectively. Any hollow in the leech shall be bridged.
The three-quarter leech height shall be taken as the three-quarter leech point.
The half luff height shall be taken as the point on the luff found by folding the head point to the tack point.
quarter luff point shall be taken as the point found by folding the head
point to the point to be used as half luff height.
|126.96.36.199||The horizontal and
vertical measurements of the headboard shall not exceed 120mm.
|188.8.131.52||The total width
of the mainsail (including the luff rope) measured at right angles to the
luff 400mm from the head shall not exceed 320mm.
Not more than four battens
are permitted in the mainsail. The batten pockets shall divide the leech
into equal parts +/- 100mm, measured to the lower edge of each pocket. The
length of the lower three pockets shall not exceed 850mm measured from
the aft edge of the sail. The upper batten pocket may extend to the mast.
The leech parts shall be taken as:
The distance from the clew point to the intersection of the leech and the centreline of
the lower batten pocket.
The distance between the intersections of the centrelines of two adjacent batten
pockets and the leech.
The distance from the aft head point to the intersection of the leech and the centreline
upper batten pocket.
|184.108.40.206||Reefing gear, Cunningham
and other tensioning devices are optional.
The jib shall be made and measured in accordance with the ISAF Sail Measurement Rules 1993 except where varied herein. Where a term or a measurement given in the ISAF Sail Measurement Rules is used, it is printed in 'italic' type.
“ISAF Sail Measurement Rules 1993” shall be taken as the “IYRU Sail Measurement
As no terms in the class rules are printed in italic type, the IYRU Sail Measurement
Rules 1993 definitions shall be used when a term used in the class rules is the same,
similar words, as one defined in the IYRU SMR 1993.
The construction shall be: Soft sail, single ply sail.
The sail shall have 3 batten pockets in the leech.
The following are permitted: Stitching, glues, tapes, bolt ropes, corner eyes, hanks, batten pockets elastic, batten pocket end caps, leech line with cleat, two windows, sailmaker label, royalty label, sail button, tell tails.
Head Point to point on foot 750mm from Tack Point...........
Head Point to point on foot 750mm from Clew Point...........
Upper width between points on luff and leech respectively 2450mm and 2300mm from the Head Point.........................
Lower width between points on luff and leech respectively 5020mm and 4720mm from the Head Point.........................
Primary reinforcement from corner measurement points.....
Secondary reinforcement from corner measurement points
for flutter patches......................................................................
for batten pocket patches........................................................
Top batten pocket inside length..............................................
Middle batten pocket inside length.........................................
Bottom batten pocket inside length........................................
the head point to the clew point, and not as shown in the diagram.
Aft “Head Point to Point on Foot”
In the diagram the point on the foot shall be 750mm from a point on the foot below the
clew cringle while in the CR text the point shall be 750mm from the clew point. The CR
text shall be taken to be correct.
top of the jib shall be straight at an angle of 90° to the luff.
The sail shall be taken to comply with this rule if the top is approximately straight and at
approximately 90° to the luff.
furling gear is optional and can be installed with its mechanism below or
above the deck. When installed below deck the forestay shall have a sealed
radial bearing system at the intersection point of the deck. If a tube is
used on the forestay it shall be enclosed in the luff of the sail.
spinnaker shall be a three cornered sail symmetrical about its centreline.
It shall not embody any device capable of altering its shape.
The sail shall be taken to be symmetrical about its centreline if, when folded in half, the
halves look to be approximately of the same shape.
These interpretations should be superseded by class rules amendments as soon as
lengths of the luffs shall not exceed 7300mm. The half width of the foot
shall not exceed 2400mm. The half width measured between points on the luffs
and the centrefold 3500mm from the head shall be 2650 +/- 50mm. The total distance
from the head to the centre of the foot shall not exceed 9000mm. This measurement
shall be taken with the sail opened out, laid on a flat surface and with
sufficient tension applied at the head and the centre of the foot just to
remove the wrinkles across the line of the measurement.
total weight of the boat shall not be less than 1450kg. Corrector weights,
if any of lead shall be laminated to the lower surface of the deck, evenly
divided, at stations two and eight.
following parts and equipment shall be include in the total weight:
following equipment shall not be included in the weight:
following parts shall, if they are permanently fixed to the boat, either
be removed before weighing or their weight shall be estimated and deducted:
position of the attachment points of shrouds and stays shall not be adjustable.
|220.127.116.11||The length of shrouds and
stays shall be altered only by turnbuckles, which shall be above the
It is permitted to adjust these while racing.
|18.104.22.168||Sail trimming devices, except the jib luff adjustment (Cunningham) and the backstay,
shall not pass through holes in the deck.
Support for crew
|A competitor's clothing and
equipment shall not weigh more than 10kg, excluding clothing (including
footwear) worn only below the knee.
ADDITIONAL RULES APPLICABLE WHILE RACING
specified in the notice of race there shall be at least two and not more than four
persons on board. The crew shall consist of the same number of persons during an
event of less than 7 consecutive days. In a World Championships the
total weight of the crew in underwear shall be a maximum of 300 kg.
|4.2||The following equipment
shall be carried on board:
anchor of minimum weight 7kg,
30 metres of 12mm minimum diameter synthetic fibre rope,
personal buoyancy for each member of the crew.
An outboard motor may be carried on board while racing.
|A.1.1||Lines drawing||A.1.2||Sectional drawing|
|A.3.5||Alternative main bulkhead|
|A.4.1||Sail Plan||A.5.1||Measurement Plan|
APPENDIX 1 - LAMINATE SPECIFICATION
|1.||HULL (SEE ALSO PLAN 3.1)
|1.2||300g/m² surface mat over whole moulding.
|1.3||2 x 450g/m²
CSM (chopped strand mat), over whole moulding.
WR (woven roving), over whole moulding.
|1.5||450g/m² CSM, over whole moulding.
|1.6||680g/m² WR, over whole moulding.
1200mm below the sheerline there shall be a 150mm wide overlapping joint.
|1.7|| 450g/m² CSM below the joint.
WR below the joint.
|1.9|| 450g/m² CSM over the keel 400-500mm wide according to plan.
|1.10||680g/m² WR as 1.9 above.
|1.11||450g/m² CSM as 1.9 above.
One 100mm wide strip of 450g/m² CSM shall be laid between floors or bulkheads and the hull.
|1.12|| The layers
shall be in the above given sequence. No layers shall be omitted nor their
|1.13||The pocket formed
by the skeg and rudder may be filled with plastic or
surfaces to be painted.
|1.15|| For assembling
of the berths to the hull a support can be used which is laminated to the
hull. This support shall consist of one fibre-glass matt 450g/mē and shall
have a maximum extension of 70 x 70mm alongside of the hull.
|2.1|| 5 x 450g/m² CSM. Construction according to plan. Flange 30mm wide.
|3.2||300g/m² surface mat over whole moulding.
|3.3|| 450g/m² CSM over whole moulding.
|3.4|| 680g/m² WR over whole moulding.
|3.5||450g/m² CSM over whole moulding.
|3.6||15mm Airex or equivalent material as indicated on plan.
|3.7||450g/m² CSM over whole moulding.
|3.8||680g/m² WR over whole moulding.
|3.9||450g/m² CSM over whole moulding.
|3.10||Deck beams to be covered with 3 x 450g/m² mat with 50mm overlap on both sides of beam.
|3.11||Sandwich construction may be substituted by a construction with deck beams in accordance with the plan and paragraph 3.10.
|3.12||Visible inner surfaces are to be painted.
|4.|| ACCOMMODATION MOULDING
|4.2||4 x 450g/m² CSM over whole
|4.3||2 x 450g/m² over the section
which forms a bulkhead.
|5.||FORWARD ACCOMMODATION MOULDING
|5.2||4 x 450g/m² CSM over whole
|6.||AFT MOULDING AND BULKHEAD
|6.2||3 x 450g/m² CSM over whole
|6.3||2 x 450g/m² CSM over bulkhead.
|6.4||Bulkhead may be made of marine
bulkheads attached to hull with 3 x 450g/m² mat on both sides.
|7.2||GRP bulkheads as in paragraph 7.1
mouldings attached to hull with 2 x 450g/m² mat.
to hull joint to be according to detail on plan.
Attachment of floors to hull to be as in paragraph 7.1 above.
|8.1||Gelcoat (can be omitted).
|8.2||300g/m² surface mat.
|8.3||5 x 450g/m²
|9.2||4 x 450g/m² CSM on both
|9.3||To be filled with Airex or equivalent
|Glassfibre of E-type glass. Resin shall be polyester suitable for marine use. All fillers are prohibited.|