“The International Rule” ( Metre Rule )
© K. Urtz 2010
chain girth skin girth
L = waterline length (LWL)
d = difference between skin girth and chain girth
S = sail area
F = freeboard ( area between the waterline and a
specified deck edge )
2,37 = a mathematical constant
The International Rule differs between classes, the smallest called 5-m and the biggest has a 23-m
rating. Best known is probably the 12-Metre Class sailing in 8 America’s Cups from 1958 to 1987.
They followed as far less expensive yachts the impressing and costly J-Class of the 30’s . Their
construction has been stopped by the Second World War. 12-m does not mean the length of a yacht
in metres. The “m” is the term for a mathematical equitation only (a recommendation to use metric
units.). The 12 Metres of the AC have a LWL of about 14 m, a total length of about 20 m and
displacements of around 20 tons. The formula keeps a balance between the below parameters. A
change of one of the figures requires the change of the others - in order not to exceed the number
12. The rule has been changed three times, the last version has following rule
Freeboard
“The International Rule” ( Metre Rule )
Around 1900 the European Yacht Clubs were looking for an
international rating rule to assure that a yacht can race in the
same class and under the same specifications in every
country. Initiated by the British YRA (Yacht Racing
Association ) and created in several international conferences
( final ones 1906 in London and Berlin ) the International
Rule (Metre Rule ) has been ratified 1907 in Paris. On this
occasion the international delegates formed the IYRU (
International Yacht Racing Union ) now replaced by the ISAF (
International Sailing Federation). As rating bodies the Lloyd’s
Register (GB) the German Lloyd (D) and the Bureau Veritas
(F) have been applied. At that time the USA has sent
observers but continued with the Universal Rule based on a
formula of N.Herreshoff.
Outfit of a conventional 12 Metre America’s Cup yacht
wave-breaker
1
Wellenbrecher
hatches / spinnaker-handling
2
Deckluken / Spinnaker-Handling.
vang track
3
Traveller für den Baumniederholer
boom vang
4
Baumniederholer
pit for the mastman
5
Cockpit für den Mastmann.
genoa coffee-grinder
6
Pedestral für die Genuawinschen.
genoa-sheet tracks
7
Traveller für die Genua-Holepunkte
mainsail coffee grinder
8
Pedestral für die Großwinsch
genoa winches
9
Genuawinschen
pit for the tailers
10
Cockpit für die Genuatrimmer
main-sheet winch
11
Winsch für die Großschot
running back-stays
12
Bewegliche Backstagen
double-wheels station
13
Doppesteuerstand
mainsail -traveller
14
Traveller für die Großschot
spinnaker winches
15
Winschen für den Spinnaker
main-sheet winch
16
Großschotsysem
rudder-blade
17
Ruderblatt
trim-tab
18
Trimmklappe
Yacht / Country : Australia II / Aus
Sail Number : 12 KA 6
Yacht / Country : Liberty / USA
Sail Number : 12 US 40
Yacht / Country
Stars & Stripes ’87 /USA
Sail Number
12 US 55
Yacht / Country
Kookaburra III / Aus
Sail Number
12 KA 15
26th AMERICA's CUP 1987
Fremantle , Australia
Fremantle , Australia
27th AMERICA's CUP 1988 San Diego, USA
Yacht / Country : “The Big Boat” / NZL
Sail Number : K KZ - 1
Yacht / Country : Stars & Stripes / USA
Sail Number : US - 1
Yacht / Country : “ALINGHI “ / CH
Sailnumber : SUI 64
Yacht / Country : " NEW ZEALAND “, NZL
Sailnumber : NZL - 82
Yacht / Country : “ALINGHI “ / CH
Sailnumber : SUI -100
32nd AMERICA's CUP2007 Valencia Spain
Yacht / Country New Zealand
Sail Number : NZL- 92
Country Yacht /: USA (former BOR 90)
Sail Number : USA - 17
Yacht / Country : Alinghi 5 / CH
Sail Number : SUI
Country Yacht / Boat#2 /NZL5 “AOTEAROA”
Sail Number : none
31st America’s Cup 2003, Auckland , New Zealand
Sailing
http://www.sailingscuttlebutt.com/ General sailing news with a useful Google search archive.
http://www.vsail.info/ The cost reduced platform of the former Valencia Sailing, with archives
of high quality pics covering 2005 - 2010 mainly.
America’s Cup
http://www.cupinfo.com/ Independent website with top news and pics about the 34th AC,its
wingsail-cats, and past America's Cup events.
http://www.sail-world.com/ Sailing, sail-racing and cruising news site updated constantly by
contributors around the world
http://www.cupineurope.com/ Ex Hauraki News, once a French-English website about the AC,
but most info disappeared. Has still a valuable list of all IACC yachts with a picture of each boat
http://www.cupedia.de/ German website about the AC of recent years
http://www.americascup.com/
Official website of the 34th AC
Websites of the Teams 2013
http://oracle-team-usa.americascup.com/
ORACLE USA defender Golden Gate YC
http://artemis-racing.americascup.com/
Artemis Racing Sweden/Challenger of Record
http://emirates-team-new-zealand.americascup.com/
Emirates Team New Zealand
http://energy-team.americascup.com/
Energy Team France
http://bar.americascup.com/
BAR/ Ben Ainsly Racing
http://www.americascup.com/en/
Team-Korea = web closed with their withdrawal
http://luna-rossa-challenge-2013.americascup.com/
Luna-Rossa-Challenge-2013/
http://china-team.americascup.com/
China-Team/
http://www.mascalzonelatino.it/ Mscalzone Latino, Italy, former Challenger of Record, Cancelled
its nomination early May 2011
12 Meter History
http://www.12mrclass.com/cms/ Website of ITMA , the International 12 Metre Association
http://sail-3d.com/12er/ Commercial sailing platform with an informative 12-Meter charter
section.
http://www.trivia.de/ Website about the German 12m Trivia with a list of all built 12-metres
http://www.ultimatesail.com/ Closed down 2011 one of the best, with much useful
information, including the Deed of Gift,the 12-Meters and the IACC yachts and their crews incl.
the 2003 AC.
http://www.usa-61.com Closed down 2011 Website of the former US owners of US 61/ AC
1987, with pics and information about her restoration
.
Recommended Links
AMERICA’S CUP HISTORY 1983 - 2013