1.

GENERAL

1.1

Purpose of the Measurement Rules

1.1.1

The One Metre is a Development Class with One Design Rigs.

1.1.2.

The intention of these class rules is to give freedom to develop the hull, keel rudder within these rules, but to ensure that rigs are as alike as possible in respects affecting performance.

1.1.3

Anything in regard to the rig not specifically permitted by these rule PROHIBITED

1.1.4

Anything in regard to the hull, keel and rudder not specifically restricted or prohibited is PERMITTED

1.6

Materials

1.6.1

Except for remote control equipment, material of higher density than lead (11.3 kg/dm3) is prohibited.

1.7

Weight and Draft

1.7.1

When measured in sailing trim and drained of water:

(a) The weight shall be 4.0 kg minimum.

(b) The draft in fresh water shall be 370 mm minimum and 420 mm maximum.

(c) The depth of the hull, measured from the waterline in fresh water to lowest point of the hull. shall not exceed 60 mm.

3

HULL

3.1

Definitions

3.1.1

The hull is defined as the boat including all equipment but excluding the rig, the keel and the rudder.

3.1.2

The structure of the hull is defined as those items which contribute to the strength and watertight integrity of the hull and includes; the hull shell, transom, keel trunking, mast trunking, bulkheads, deck, deck beams, hatch coamings, hatch covers, similar structural items, and their stiffening or reinforcement; and excludes plastic or readily removable containers of remote control equipment.

3.2

Identification Marks

3.2.1

The boat's national letters and registration number shall be:

(a) Painted on, engraved in or moulded in an easily visible location.

(b) Displayed on the external surface clearly and legibly with a minimum height of 20 mm 

Registration through PRSC as acting organizing body temporarily.

3.3

Materials

3.3.1

Subject to 3.3.2 the structure of the hull shall be made of and joined using one or more of the permitted materials listed below:

(a) Metal with the exception of expanded, foamed and honeycombed metal.

(b) Wood and wood based products containing no non-permitted materials and with the exception of honeycombed material.

(c) Glass fibres.

(d) Gel coat, resin, adhesive, varnish, paint.

(e) Film covering materials which may be woven or partly woven.

(f) Elastomeric material.   (rubber or silicone)

(g) Sheet plastic, which may be vacuum moulded, containing no non-permitted materials, and with the exception of foam plastic.

3.3.2

Resin used for bonding glass fibres shall be un-pigmented and the interior shall be unpainted, except as in 3.2.1, to allow inspection of the fibres 

This is to allow inspection of hull for prohibited materials.

3.3.3

Unrestricted by 3.3.1, a builders mark may be applied in accordance with the IYRR

3.4

Construction

3.4.1

The hull shall be a monohull of maximum length 1,000 mm.

3.4.2

The forward 10 mm of the hull shall be made of elastomeric material. 

This constitutes the "bumper", made of rubber, silicone ,etc.

3.4.3

Except for hollows or voids formed by the keel trunking and rudder tube:

(a) Hollows which exceed 3 mm or voids in the underwater profile or the plan view of the hull are prohibited.

(b) Hollows in the undersurface of the hull, tested transversely and parallel to the waterline, shall not exceed 3 mm.( see below)

4

KEEL AND RUDDER

4.1

Definitions

4.1.1

The keel is defined as the fin, the external ballast and any fastenings used to attach the external ballast to the fin.

4.1.2

The rudder is defined as the rudder and the stock excluding steering attachments at the head of the stock

4.2

Construction

4.2.1

One keel and one rudder only are permitted

4.2.2

The keel and/or rudder shall not have openings through which water could pass

4.2.3

The keel and rudder shall be removable from the hull.

4.2.4

Articulated keels and keels which can be moved or rotated relative to the hull are prohibited

4.2.5

The rudder shall be placed aft of the keel and shall not project aft of the hull. Articulated rudders are prohibited

4.3

Weights

4.3.1

The weight of the keel shall be 2.2 kg minimum and 2.5 kg maximum

4.3.2

The weight of the rudder shall not exceed 75 grams

5

RIG

5.1

Definition

5.1.1

A rig is defined as a mast, a mast stub and/or joiners if used. a mainsail and its boom, a jib and its boom, permitted fittings and rigging.

5.2

Materials

5.2.1

MAST AND BOOMS

The principal material shall be alloy, with a minimum of 90% aluminium content, or wood. The other permitted materials are: adhesive, wax, varnish, paint or powder coat finish. Alloy may be anodised.

5.3

Masts

5.3.1

Construction

(a) When in racing trim, measurements shall comply with the measurement diagram.

(b) Masts may be stepped on or through the deck.

(c) A mast stub arrangement is permitted.

(d) Measurement bands shall be of a colour which contrasts with the mast, may be of any material and shall be between 3 mm and 10 mm wide.

(e) Between the lower edge of the upper measurement band and the upper edge of the lower measurement band:

(i) The mast cross section shall be round, 10.9 mm minimum mean diameter, with constant external (and internal where hollow) section. The section may contain an internal luff groove.

(ii) Internal and/or external joiners shall not exceed 100 mm in length.

5.3.2

Fittings

Each mast may have:

(a) Windvane or other indicator and/or its attachment.

(b) Backstay crane.

(c) Attachment for the jib stay and/or halyard.

(d) Attachments for the shrouds.

(e) Pair of spreaders and their attachments.

(f) Attachments for the mainsail luff, head and tack.

(g) Mast strut and/or its attachment.

(h) Checkstays and/or their attachments.

(i) Gooseneck and/or its attachment.

(j) Kicking strap and/or its attachment.

(k) Mast deck fitting.

(1) Mast heel fitting.

(m) Rig corrector weight/s.

5.3.3

Rigging

Each mast shall be supported by:

(a) Jib stay and/or halyard.

(b) Pair of shrouds

(c) Backstay

5.4

Boom

5.4.1

Construction

a) Booms shall be of constant external (and internal where hollow) cross section with the exception of the last 10mm at each end. The maximum external cross section shall not exceed 20 mm.

b)The upper edge of the boom shall not have a permanent set exceeding 3mm measured to a straight line between points 10mm from each end of the boom.

5.4.2

Each boom may have:

a) Attachments for the mainsail tack, sheet, and clew.

b)Kicking strap and/or its attachment.

c) Counterweight and its attachment

5.4.3

Jib Boom Fittings

a) Attachments for a jib stay, tack, sheet, clew and topping lift

b) Boom Swivel and/or its attachment.

c) Gooseneck and/or its attachment

5.5

Other Rigging Rules

5.5.1

Unless otherwise specified, all fittings and rigging may be adjustable.

5.5.2

Masts and booms may be drilled for the purpose of attaching fittings and rigging.

5.5.3

If used, rig corrector weights shall be below the lower mast measurement band

5.5.4

Checkstays may be fitted only when the mast is stepped on deck and no mast strut is fitted. They shall be attached to the mast no more than 100mm above the deck. They shall act only in tension.

5.5.5

The kicking strap shall act only in tension from below the main boom.

5.5.6

The tack point and/or the clew point shall not extend more than 25mm beyond the end of a boom.

5.5.7

The jib boom swivel shall be placed approximately on the centerline of the hull. The alignment of the swivel shall be controlled only by the rig tension.

5.5.8

A line taken through the jib tack point and head point shall not cut the forward face of the mast higher than the lower edge of the middle measurement band when the jib is on the centreline of the hull.

5.5.9

A jib topping lift may be attached to the jib stay and/or halyard, or their attachment to the mast.

5.5.10

In order to prevent fouling of a topping lift, a line may be attached to and /or passed around any of the following: the topping lift; its attachments at either end; the jib; the jibstay.

5.5.11

No part of a rig shall project beyond the extreme ends of the hull.

Tolerances for Mast & Boom Section

Roundness

The amount by which two diameters measured at right angles at the same section may differ is 0.5mm maximum

Mast Section

The amount by which the mean of two diameters measured at right angles at the same section may differ along the mast is 0.5mm maximum

Boom Section

The amount by which any dimension may differ along the boom is 0.5mm maximum

6

SAILS

6.1

General

6.1.1

Sails shall be single ply soft sails made and measured in accordance with the current 'IYRU Sail Measurement Rules', except where varied herein. Where a term defined or a measurement given in the IYRU Sail Measurement Rules is used in these rules it is printed in 'italic'type. 

Mylar sails are allowed

6.1.2

Sails shall comply with the measurements on the measurement diagram.

6.1.3

During measurement battens need not be removed and sails may remain attached to spars

6.1.4

The same cloth shall be used throughout the body of a sail

6.1.5

With the exception of sail identification marks, added paint, dyes or other decorations which stiffen the cloth shall be regarded as reinforcement

6.1.6

Seams, including their reinforcement, and tablings shall not exceed 15 mm in width.

6.1.7

Corner reinforcements shall not exceed 125 mm measured from each corner measurement point

6.1.8

Flutter patches are permitted but shall fit within a square of 50 mm side.

6.1.9

Discontinuous attachments on a sail luff shall be disregarded for the purpose of measurement provided that their total length, measured along the luff, does not exceed 10% of the length of the luff and that the longest attachment is no more than twice the shortest.

6.1.10

Telltales may be fitted to mainsail and/or jib.

6.1.11

Cringles and eyes not exceeding 10 mm in diameter may be used at attachment points.

6.2

Mainsails

6.2.1

Each mainsail shall be made of a maximum of four panels joined by seams which shall not be closer than 150 mm to a corner measurement point.

6.2.2

With the exception of a double luff any method of attachment to the mast is permitted.

6.2.3

Where a mainsail is fitted with a bolt rope or sliders which is/are held in a recess in the mast, the sail shall be measured ignoring the rope or sliders

6.2.4

The leech shall not be convex between adjacent battens, between the clew point and the adjacent batten or between the aft head point and the adjacent batten.

6.2.5

The foot shall not be convex between the tack point and clew point

6.2.6

There shall be three battens on the leech. The distances from the centreline of a batten on the leech to the adjacent leech pointshall not exceed 20 mm.

6.2.7

The upper batten shall not exceed 1 0 x 75 mm and any pocket/reinforcements shall not exceed 25 x 95 mm.

6.2.8

The two lower battens shall not exceed 1 0 x 1 00 mm and any pocket/reinforcements shall not exceed 25 x 120 mm.

6.2.9

No part of a mainsail shall extend above the lower edge of the upper measurement band or below the upper edge of the lower measurement band.

6.3

Jibs

6.3.1

Each jib shall be made of a maximum of three panels joined by seams which shall not be closer than 100 mm to a corner measurement point.

6.3.2

The luff tabling may envelope the jib stay.

6.3.3

The leech shall not extend aft of a straight line from the clew point to the aft head point

6.3.4

The foot shall not be convex between the tack point and clew point

6.3.5

There may be two battens. The position of the battens, if fitted, shall comply with the measurement diagram.

6.3.6

The battens, if used, shall not exceed 10 x 75 mm and any pockets/reinforcements shall not exceed 25x95mm.

6.4

ldentification Marks

6.4.1

Sails shall carry identification marks in accordance with the IYRR

7

EQUIPMENT

7.1

Replacements

7.1.1

Except in cases of authentic damage or loss the following equipment shall be used during an event: one rig of each size, one keel and one rudder

7.2

Prohibited

7.2.1

Sails of different rigs shall not be used together

7.2.2

Except in cases of authentic damage or loss, a mainsail or jib may not be used alone

7.2.3

Not more than two remote control functions shall be used. One may control only the rudder and the other may control only the main and jib sheets simultaneously

© ISAF, 1995