The Evolution of Sailing Multihulls, part one, by François Chevalier
French naval architect François Chevalier presents the evolution of
sailing multihulls in this first part of a larger and upcoming series.
Jacques Taglang & François Chevalier's original stories are here, here and here.
All content is courtesy of the author, I simply took the liberty of
producing this translation which was subsequently published in the
Journal of the Westlawn Institute of Marine Technology.
This series will be an opportunity for us to present a history of multihull design, showcasing some of their curious features, not all of them successful, and delving into the inventive mind of the speed-crazed mariner. We shall discuss the origins of the type in antiquity, the major evolutions of the 19th and 20th century, all the way to the 2013 America's Cup.
Origins
In parallel to our analyses of the drag-racing machines built for the
34th America's Cup, it is interesting to pursue their history. Their
origins lie in the Oceania pirogue: These catamarans, trimarans and
proas were already described as "flying objects" by Antonio Pigafetta,
who, serving as Magellan's assistant during the World's first
circumnavigation, was the first to describe these boats in 1521.
To understand the geographical distribution of these craft and how
their design evolved, I have plotted the island-hopping movements of the
Pacific peoples on the chart below, from Madagascar to the furthest
reaches of the Pacific ocean:
The migrations were carried out in consecutive waves over a period in excess of 50,000 years.
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The migrations were carried out in consecutive waves over a period in excess of 50,000 years.
The first wave saw settlers in Indonesia, New Guinea and Australia
during the last Ice Age: Indeed, between 50,000 and 35,000 BC, a 150
metre drop of the sea level enabled the Sunda and Sahul peoples to
progress towards the East and South (in green on the chart).
In 4,000 BC, other peoples came by way of the Taïwan Sea and
intermingled with established populations. From 1,600 BC, this
population scattered throughout Micronesia (the Marianas Islands,
Marshall Islands, etc…) and later in Melanesia; In 1,000 they reached
western Polynesia including Fidji, Tonga, Samoa (in blue on the chart).
Five centuries would pass before Polynesians would resume their
migrations, spreading to Tahiti and the Marquesas Islands. From these
archipelagos, a new migratory wave started: Settlers are believed to
have reached Hawaii and Easter Island circa 400 AD. Meanwhile,
migrations in the Indian Ocean reach Madagascar and surrounding lands
around the year 600. Finally, settlers landed on New Zealand around the
year 700 (in orange on the chart)
As the explorers of the "Old World" first ventured into the Pacific,
they were immediately baffled by the speed of the craft that they
encountered there. They were even more surprised to realise that the
same craft had been used to reach these distant islands at the far
reaches of the largest ocean.
If Pifagetta's account of the Ladrones island (modern-day Marianas)
is an entertaining read, his description of the proa did not elaborate
much. Thomas Cavendish also travelled there and was impressed by the
number of these craft. In 1616 Jacob Le Maire gave a picturesque
description of the catamarans that he came across in the Tonga Islands.
In 1686, William Dampier measured their speed, assessing that these
craft "are the fastest in the World, setting 18 knot averages over
hundreds of miles".
When William Funnell sailed about the Pacific islands in 1705, he
sketched a fanciful "flying proa", whilst Woodes Rogers disassembled one
and put her on display six years later in Saint James Park in London.
The first actual plan (featured above), though full of inaccuracies, was
drafted by Piercy Brett in 1742 whilst serving on George Anson's voyage
around the World. It appears that it was exceptionally difficult for
Europeans to understand how these sailing craft operate. François-Edmond
Pâris' works were the first to cover the subject in depth when they
were published in 1839; followed by those of James Hornell (1936) and
Jean Neyret (between 1959 and 1976).
Here we shall discuss six types of pirogues that best describe the
rich, versatile and inventive minds of these seafaring peoples.
The Marianas proa
The first of the craft to be discovered were the proa of the Islas Ladrones (nowaday Marianas), a thousand miles off New Guinea.
The Marianas proa
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The first of the craft to be discovered were the proa of the Islas Ladrones (nowaday Marianas), a thousand miles off New Guinea.
This model is chosen from a drawing by Piercy Brett, twelve metres
in length, featuring a dugout hull with two lateral boards and with two
symmetrical bows on either end: It is a double-ender. The boat was sewn
over with a watertight fabric (a skin) that covers the lateral boards
and the bows. The mast was maintained upright by a strut stepped where
the longitudinal stringers meet on the windward outrigger. A shroud
fastened in the same place also stayed the mast. The outrigger was held
in position by a vertical peg bound to each crossbeam by a lashing.
During tacks (or conversely gybes), the sail was moved from forward to
aft by swivelling the mast, and the paddle on the opposite bow would
then serve as the rudder. The hull could be made of several parts and
overlaid lateral planks. According to navigational needs, they sometimes
placed a board over the crossbeams; in other cases a leeward outrigger
was added, enabling the use of a much wider boarded platform. The
asymmetric hull and outrigger gave the craft remarkable upwind
performance, and George Anson wrote that these pirogues "are able to
close the wind better than any other known vessel", an astounding
observation given that the design of these boats were 3,000 years old!
The Bismarck & Louisiade proas
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The diversity of the rigs found on sailboats in the Bismarck and the Louisiade Archipelagos, illustrated above and below with two large proas, indicates strong influence from Indonesia.
These sails can also be found on ancient sculptures on Java. Without bringing up any controversy on the original inventor of the rigid wingsail, these particular ones were made of braided leaves, herego rather stiff. The whole sail could swivel around its fastenings at the top of the masts, creating optimal lift depending on strength and incidence of the wind.
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These proas typically measured 10 to 15 metres in length, but larger ones between 18 and 25 metres were also built, serving mainly for long passages or for ceremonial use. The masts were held in position by rounded buttresses and by forestays fastened on the windward outrigger. The Louisiade "Lia-No", with a distinctive elliptical sail, featured flaring and clinker-built topsides that greatly reduced deckwash. The semi-circular sections of the hull were also a perfect example of wetted surface reduction.
The Fidji catamaran
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Following the long string of islands in the eastward prolongation of New Guinea, settlers finally found Fidji.
The catamaran of the Fidji islands was an assembly of two pirogues. If disassembled, they could each be fitted with an outrigger. Each hull was made of one or more dugout tree trunks, depending on the length of the craft (between 12 and 24 meters), with a freeboard increased by overlaying elements on the topsides, all neatly adjusted and sewn up. The two parallel hulls were positioned in a Quincunx, with one slightly ahead of the other. The bows were vertical like modern multihulls. On large catamarans, the space between hulls was covered with decking. The craft was steered by two leeward paddles, one per hull. The triangular sailing rig was set on the leeward hull, with the windward hull used as an outrigger. To tack, the sail was stowed on the topyard, the rake in the mast was decreased as the rig was carried over to the other hull.
The Tonga catamaran
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The catamarans from the Tonga islands have been widely illustrated by the first explorers, particularly Willem Schouten, Abel Tasman and James Cook. Daniel Lescallier reproduced their plans in his Traité pratique du gréement des vaisseaux, but a few details were missed out.
The Tonga island catamarans were of large size, between 15 and 25 meters in length, able to carry up to 150 passengers. A small dugout was usually kept aboard and used as a tender. They were used to sail to destinations in Melanesia and Micronesia. The platform was placed atop vertical boards and stayed supports. Each hull would be decked and feature a long hatch giving access to the bilges to scoop out shipped water whilst in rough seas or at high sailing speeds. Typically, the boat featured a semi-circular hut with a cooking stove near the mast foot. The mast was rather short, with a jawed masthead that carried the topyard. The mast was held in position by two lateral deck spreaders, similarly to wingmasts on modernday Open 60s. For short beats to windward, the sail came naturally against the mast, similarly to lateen sails on "the wrong tack", but for long tacks, the mast would be swivelled vertically in order to pass the sail over from one side to the other. The two paddles were always positioned to leeward.
The Zanzibar trimaran
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Finally, the last example of these antique craft is a trimaran that was prevalent along the African coast, the Comoro Islands and Madagascar.
This particular trimaran was drawn in Zanzibar in the early 20th century, and a few of her kind are still afloat to this day. If the loose-footed sail is an Arab trait, the actual design of the craft is of Indonesian influence. The bottom of the two outriggers on either side were flat and faced outwards, similarly to waterskis or hydrofoils. The sail was set on a short mast, in the centreline of the craft, and changed tacks on every beating leg. Measuring 7 to 9 metres in length, these machines could sail at similar speeds to modern multihulls.
All these "light vessels", as described by our forebears, would ship a lot of water and at any oone tilme, at least one crew member would be tasked with scooping the water out, whether it be during fishing or on a open sea passage. But if there was a compromise, it was all for speed.
Herreshoff era catamarans
If the catamaran, trimaran or proa instances of the pirogue were born
several thousand years ago in Oceania, the first modern catamaran of
western design was built in England for Sir William Petty in 1662, at a
time when the word "yacht" was a very new word. And it would take a
yachtbuilder to make the greatest leap in multihull design after that.
The World's first multihull with a racing designation was Nathanael
Greene Herreshoff's. He explained his thinking in the New York Herald on April 16th, 1877:
[…] In the fall of 1875 I was thinking and thinking how to get great speed out of single hulled boats, of the kind in common use. To get great speed, thought I, one must have great power, one must have a great sail, you must have something to hold it up, and that something must be large and wide, and have a large sectional surface, and also a great deal of frictional surface. These properties in a hull to give stability are not compatible with attaining great speed. Indeed, the more one tries to make a stiff, able hull the less speed will be attained, even if corresponding additions are made to the sail. So then, there are two important principles of speed which constantly work against each other. If we increase the power to get more speed we must increase the stability of the hull correspondingly. An increased hull has more resistance, both from sectional area and surface friction. So what we would gain one way we must lose in the other. Well, a boat must have width, and the wider she is, generally speaking, the more stable she will be. But a wide boat cannot have great speed, however much power you will apply to her. So the next thing that is to be done is to decrease the sectional area and, in a measure, retain stability; the boat would have power to lift at a distance each side of the keel, where it would do great work. I kept on following this principle, getting the keel higher and higher, until by and by the keel came out of the water, when, lo and behold! there was the double boat! Nothing else to be done but take a saw and split her in two, spread it apart a little way, and cover all with a deck, and there you are! That was the rough road which I travelled, and having arrived thus far I abandoned my ill-shaped hulls, and in their place substituted them with two long, narrow, very light boats and connected them at the bow, stern and middle. […]
Even as Mr. Herreshoff was reinventing the catamaran, it is surprising that the type was not a firmly established concept - The testimonies of explorers in previous centuries had unanimously described the craft's performance - but was merely the result of a reflection on the optimization of performance in monohulls.
Herreshoff's thinking
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Starting with the monohull in (1), Mr. Herreshoff increased the beam to increase stiffness (2); As the beam was further increased the keel was raised and the maximum draught was offset from the centreline to either side (3) until the keel was completely out of the water. It could have been simpler to split the boat along the centreline and spreading them apart (5), but evidently Mr. Herreshoff eventually proposed two narrow hulls (6).
On June 24th, 1876, the day after the Centennial Regatta, The World printed:
The catamaran Amaryllis, constructed by Mr. Herreshoff, of Providence […] fairly flew along the Long Island shore, passing yacht after yacht as if they were anchored. As Amaryllis dashed over the line a winner she was saluted by guns from the yachts that were lying at anchor, and the excursion steamers screeched their loudest in honor of her victory.
The World also printed an editorial on page 4, excerpt:
A Revolutionary Yacht
Nobody protested against entering her for the race yesterday, for the reason probably that everybody expected to beat her, but everybody seems to have objected to being beaten by her. It behooves the owners of the large schooners, however, to take counsel together lest somebody should build an Amaryllis a hundred feet long and convert their crafts into useless lumber. It is a matter quite as important as keeping the America's Cup.
Nobody protested against entering her for the race yesterday, for the reason probably that everybody expected to beat her, but everybody seems to have objected to being beaten by her. It behooves the owners of the large schooners, however, to take counsel together lest somebody should build an Amaryllis a hundred feet long and convert their crafts into useless lumber. It is a matter quite as important as keeping the America's Cup.
The Centennial regatta and the little catamaran aberration would have seemed very distantly related to the traditional America's Cup schooners of very large size, but the reporter spelled out a glaring premonition: the future of regattas, and indeed, the America's Cup itself, were put into question on the day that the very first American catamaran set sail. Eventually, the America's Cup was defended with a catamaran, Dennis Conner''s Star & Strioes in 1988.
John Gilpin (Nathanael Herreshoff)
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The lines and sailplan of the John Gilpin (1877) were first published in 1870-1887 American and British Yacht Designs (François Chevalier & Jacques Taglang, 1991). The drawings emphasise the elaborate and subtle design of Herreshoff catamarans. Besides the two narrow hulls, the complex assembly with spherical joints and tensioners made the yacht an expensive purchase.
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Catamaran
Designer: Nathanael Greene Herreshoff
Builder: Herreshoff Manufacturing Company
Introduced: 1877 (four built)
Length: 9.75m
Load Waterline Length: 9.37m
Beam:5.28m
Draught: 0.50m / 1.26m
Displacement: 1.5T
Upwind sail area: 85sqm
It is interesting to delve into the designer's thinking, and to stop at step (4), where the centreline keel was effectively raised above water: Mr. Herreshoff's "ill-shaped hulls". In 1898, twenty-three years after the launch of the Amaryllis, Canadian designer George Herrick Duggan sought to reduce the wetted surface of his one-tonner to defend the Royal St. Lawrence Yacht Club's tenure of the Seawanhaka Cup. The rating rule only took into account the load waterline length. With their extremely long overhangs, powered up yachts would heel and in effect increase their sailing waterline length. To benefit from this, the deck would look increasingly rectangular from overhead.
In Dominion Duggan created a double-hull by raising the centreline keel; With a wetted surface reduced by 30%, he easily defenced the cup! Facing the pressure of angry contenders however, the Seawanhaka rating rule was amended to ban double hulls in subsequent races, by requiring the maximum draft of sections to lie on the centreline of the yacht. This however did not prevent another naval architect known for bold designs, Bowdoin B. Crowninshield, to exploit this loophole and engineer the trimaran Hades in 1902 for the Quincy Cup, though incidentally she would prove fruitless in the face of competition given by Starling Burgess' defence candidate Outlook, one of history's most extreme scows.
Though catamarans threatened to change the course of yachting history both in 1876 and in 1898, to no avail, they failed to convert yacht clubs as rating rules were amended to prevent them.
One-tonner Dominion (George Herrick Duggan)
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Dominion is a development of the scow, measuring 10.85m overall and only 5.28m on the waterline. By raising the centreline keel above the water so as to increase stiffness and reduce wetted surface, the designer created a catamaran.
Dominion
One-tonner (Seawanhaka Cup)
Designer: George Herrick Duggan
Launched: 1898
length: 10.83m
Load Waterline Length: 5.28m
Beam: 2.31m
Draught: 0.28m / 1.70m
Upwind sail area: 45sqm
Hades (Boudoin Bradlee Crowninshield)
Hades, measuring 16.75m overall and 6.40m on the waterline, is a pseudo-trimaran, the vaka or centreline keel only present to exploit a loophole in the rating rule which requires maximum draught of the sections to lie on the centreline of the yacht. The plateform is so thin that it needs a supporting tensile structure above decks.
One-tonner (Seawanhaka Cup)
Designer: George Herrick Duggan
Launched: 1898
length: 10.83m
Load Waterline Length: 5.28m
Beam: 2.31m
Draught: 0.28m / 1.70m
Upwind sail area: 45sqm
Hades (Boudoin Bradlee Crowninshield)
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Hades, measuring 16.75m overall and 6.40m on the waterline, is a pseudo-trimaran, the vaka or centreline keel only present to exploit a loophole in the rating rule which requires maximum draught of the sections to lie on the centreline of the yacht. The plateform is so thin that it needs a supporting tensile structure above decks.
Hades
Hybrid catamaran (Quincy Cup)
Designer: B. B. Crowninshield
Launched: 1902
Length: 16.75m
Length overall: 22.40m
Load Waterline Length: 6.40m
Beam: 5.18m
Draught: 0.36m / 2.5m
Upwind sail area: 185sqm
Hybrid catamaran (Quincy Cup)
Designer: B. B. Crowninshield
Launched: 1902
Length: 16.75m
Length overall: 22.40m
Load Waterline Length: 6.40m
Beam: 5.18m
Draught: 0.36m / 2.5m
Upwind sail area: 185sqm
If multihulls did not achieve a popular success in the 19th century, they were never actually abandoned. Every edition of the American Register of Yachts listed in excess of ten cruising or racing catamarans.
The Sailing Machine (Lewis Francis Herreshoff)
In Lewis Francis Herreshoff's (1890-1972) book The Common Sense of Yacht Design (published 1948), he denounced the controversy endured in 1876 by his father Nathanael Herreshoff, which created a void in the development of fast sailing yachts. In his chapter titled The Sailing Machine, which assesses the future of yachting, he proposed several catamarans, including the above, with two hulls borrowed from power yachts, and two swivelling and rotating wingsails set on a quadripod rig.
The Sailing Machine (Lewis Francis Herreshoff)
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In Lewis Francis Herreshoff's (1890-1972) book The Common Sense of Yacht Design (published 1948), he denounced the controversy endured in 1876 by his father Nathanael Herreshoff, which created a void in the development of fast sailing yachts. In his chapter titled The Sailing Machine, which assesses the future of yachting, he proposed several catamarans, including the above, with two hulls borrowed from power yachts, and two swivelling and rotating wingsails set on a quadripod rig.
The Sailing Machine, which L. Francis Herreshoff proposed in 1948, demonstrated that besides the designer's great drafting talent, capable of turning out plans of utmost precision, he also had a very creative imagination: He would give proof of this with his next catamaran, Sailski.
The Sailing Machine
Wingsail ketch catamaran
Designer: Lewis Francis Herreshoff
Proposed: 1948
Length: 9.15m
Load Waterline Length: 8.85m
Beam: 5.35m
Draught: 0.67 / 1.15m
Upwind sail area: 44sqm
Sailski (Lewis Francis Herreshoff)
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By designing the more prosaic catamaran Sailski L. Francis Herreshoff proposed many new ideas which became commonplace forty years later. The plans for the Sailski were published in The Rudder magazine between May 1949 and February 1950, and three were built between 1952 and 1966. The Sailski's asymmetric hulls served as lateral lift and her tripod rig reduced the load of the mast on the crossbeams, all of which were aerodynamically faired. She was the first catamaran to feature a trampoline but the crew did not likely somersault like on modern-day AC45s!
L. Francis Herreshoff met the demands of The Rudder readership who wanted a version of the Sailing Machine catamaran that would be cheap, lightweight, fast and easy to build. The Sailski measured 27 feet in length and announced the development of beach catamarans.
Sailski
Catamaran
Builder: amateurs
Designer: Lewis Francis Herreshoff
First built: 1952
Length overall: 8.23 m
Load Waterline Length: 7,33m
Beam: 4.71m
Draught: 0.20m / 0.93m
Upwind sail area: 23sqm
Catamaran
Builder: amateurs
Designer: Lewis Francis Herreshoff
First built: 1952
Length overall: 8.23 m
Load Waterline Length: 7,33m
Beam: 4.71m
Draught: 0.20m / 0.93m
Upwind sail area: 23sqm
Beach cats
After discussing the origins of multihulls with the pirogues in Oceania and with 19th/early 20th century racing multihulls, let us delve into the post war catamarans. Out of hundreds of beach catamarans developed in this period, with some built in a few numbers locally and with others seeing worldwide success, we shall shortlist only a few here. While the history of catamarans has already been told by others, the idea here is to relate the evolution of hull shape through a couple of models which have characterized production.Yvonne
It may be surprising that Nathanael Herreshoff never mentioned Oceania pirogues, but in Australia, dinghy builders Charles Cunningham and his son Lindsay, then an engineering student, were fascinated by these early Pacific multihulls. In 1952 they built a prototype which, two years later, they developed into a 20ft (6.09m) catamaran, christened Yvonne after Charles' younger sister. In 1956 Charles & Lindsay won the first national championships in the class, which is still raced actively to this day.
Designed for amateur building, with a V deadrise, almost flat aft, and with a distinctive bow overhang, the Yvonne is particularly at ease in a seaway. The class established itself very fast, despite strong competition and new production models developed by her designers, and was always adapted to innovations, offering a double trapeze and a spinnaker in 1960.
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Yvonne
Catamaran
Designers: Charles & Lindsay Cunningham
Introduced: 1954
Length Over All: 6.09m
Load Waterline Length: 4.66m
Beam: 2.73m
Hull beam: 0.45m
Draught: 1m / 0.18m
Air draught: 7.83m
Weight: 236kg
Mainsail area: 12.8sqm
Jib area: 4.8sqm
Asymmetric spinnaker area: 23sqm
Build: marine plywood or GRP
Patin a Vela
The Patin a Vela was born during the 1920s near Barcelona. It all started from a paddleboat on which one would have stepped a mast and set a sail, without adding a rudder or a centerboard. After the Second World War, a class was eventually created to normalise all the different types that had developed in Catalogna. There is nothing more convenient than a simple boat that can go as soon as the sail is set!
By moving from forward to aft, the crew changes the centre of drift and the boat heads up or bears away. For tacking, the crewhand positions oneself at the foot of the mast and rolls the boat on her forward sections.
Initially designed for the warm climes of the Mediterranean Sea, the Patin a Vela eventually achieved a worldwide appeal.
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Patin a Vela
Catamaran
Introduced: 1943
Length of Hull: 5,60m
Load Waterline Length: 5.06m
Hull waterline beam: 0.25m
Beam: 1.60m
Draught: 0.32m
Air draught: 7m
Weight: 110kg
Mainsail area: 11.70sqm
Build: marine plywood or GRP
Shearwater
Brothers Roland & Frank Prout were first known as British canoe champions and also as olympians. Later, they started building double hulled boats by assembling kayaks with bamboo canes, before creating the Shearwater catamaran in 1954 with which they won the Burnham dinghy regatta. In 1956, they developed the Shearwater III and won the Cross Channel dinghy race.
The sleek bows and lifting aftersections made this boat prone to negative pitch angle, but the elliptical shape of the sections eased her movements somewhat, all the while keeping a large reserve buoyancy.
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Shearwater
Catamaran
Designers: Roland & Francis Prout
Introduced: 1954
Length of Hull: 5,06m
Load Waterline Length: 4.85m
Hull waterline beam: 0.36m
Beam: 2.25m
Draught: 0.15m/0.84m
Air draught: 7.14m
Weight: 140kg
Jib area: 4.22sqm
Mainsail area: 10.34sqm
Upwind sail area: 10.56sqm
Build: moulded wood or marine plywood
Exocet
In France, Lucien Gomez is known as the godfather of sport multihulls. In 1957 he designed and built the Exocet, a larger and loftier catamaran than the Shearwater. Her lines were more full-bodied, she also featured deflectors on each bow that reduced spray and pitch-poling. A lenticular floater on the masthead prevented the Exocet from turning turtle during capsizes.
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Exocet
Catamaran
Designer: Lucien Gourmez
Builder: La Prairie (France, 1961)
Introduced: 1956
Length of Hull: 5.13m
Load Waterline Length: 4.87m
Beam: 2.35m
Hull beam: 0.58m
Draught: 0.13m/0.75m
Air draught: 7.82m
Weight: 140kg
Upwind sail area: 17sqm
Build: GRP
Shark
In 1959, Rod Macalpine-Downie (1934-1986) took commission of his first catamaran, christened Thai III, which outclassed the Shearwater. In 1962, the Thai Mk.IV won all six regattas in the European one-of-a-kind regatta. In the same year, his C-Class Hellcat won the first Little America's Cup at Sea Cliff, NY. Thereafter he endeavoured to promote the Shark catamaran, designed by his business partner Dick Gibbs, throughout the USA, earning a lot of silverware, including the One-of-a-kind regatta in Miami in 1963.
The Shark, a folding boat, was a fast and safe catamaran that earned a resounding success. Gibbs & Macalpine-Downie furthered their business with another 80 different designs with a career production in excess of 150,000 boats. Macalpine's final model, the third version of the Crossbow, was created as a record breaking craft with a design speed of 60 knots.
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Shark
Folding catamaran
Designers: Rod MacAlpine-Downie & Richard Gibbs
Introduced: 1962
Length Overall: 6.09m
Load Waterline Length: 5.43m
Beam: 3.05m
Hull beam: 0.54m
Draught: 0.76 / 0.16m
Air draught: 9.34m
Weight: 136kg
Upwind sail area: 25.5sqm
Build: moulded wood
Tornado
In 1967, the International Yacht Racing Union introduced the B-Class International championships (crew of two, 20ft LOA, 10ft beam, 21.8sqm of sail). Reginald White & Bob Fisher won the first edition on a Tornado, designed in the previous year by Rodney March. This boat became an olympic class in 1976 at the Montreal Games, and was used at every summer Olympics until the 2008 Games. The Tornado is the only B-class that achieved such success, and is widely considered to be the fastest production catamaran of the 20th century.
As an olymic class, the Tornado evolved naturally and over time underwent several technological developments. Famous olympic medallists include Swede Goran Marstrom (1 bronze medal), Brazilian Lars Grael (Torben Grael's brother, with 2 bronze medals), Frenchman Nicolas Hénard (2 gold medals with a different crew), Austrians Roman Hagara & Hans Peter Steinacher (two gold medals); Australians Darren Bundock, Mitch Booth and Glenn Ashby all won olympic medals too and now actively sail in the AC45 World Series.
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Tornado
Catamaran
Designer: Rodney March
Introduced: 1966
Olympic class: 1973-2008
Length Overall: 6,09m
Load Waterline Length: 5,70m
Beam: 3,05m
Hull beam: 0,42m
Air draught: 0.80m / 0.16m
Air draught: 9.66m
Weight: 153kg
Mainsail area: 17sqm
Jib area: 7sqm
Spinnaker area: 25sqm
Build: moulded wood or GRP
Skate 14
The Skate 14 is an old project that I had kept in the drawer. The Patin a vela had appealed to me when I was studying architecture at the Beaux Arts de Paris. I imagined my own take of the same concept, with shorter length and more elaborate asymmetric lines, but keeping in scope with the original, with minimal deck fittings, the boat would also ne easy and fast to step the rig and set sail. The idea was to create sufficient volume when heeling to compensate for the shortened hull, while maintaining lateral lift on the after sections.
I completed a hull mould and tried to persuade an uncle who managed a shipyard building GRP Vauriens and Caravelles in Southern Brittany, but he resented innovation, so I take the opportunity of writing this story to modernise the rig of this small Patin a Vela.
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Catamaran
Designer: François Chevalier
Introduced: 1969
Hull length: 4.30m
Load Waterline Length: 4.05m
Hull waterline beam: 0.16m
Beam: 1.80m
Draught: 0.25m
Airdraught: 6.55m
Weight: 80kg
Mainsail area: 7.66sqm / 8sqm
Build: GRP
Hobie Cat 16
At 21 years of age, Hobart "Hobie" Alter opened his surfboard shop at Dana Point, CA. Two years later, in 1956, he developed a method to shape polyurethane foam core and became a reference for surfboards. In 1968, he introduced the Hobie 14, which featured asymmetric hulls with a distinctive banana sheerline and trampoline set on a raised anodised aluminium frame. The first Hobie was a foam core and GRP sandwich build with retracting rudders and no daggerboards. In the following year, the Hobie 16 was developed and a distribution network was established throughout the American territory. In 1972, the Hobie Cat became the World's bestselling catamaran.
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Hobie Cat 16
Catamaran
Designer: Hobart Alter
Builder: Hobie Cat Europe
Introduced: 1969
Length overall: 5.04m
Load Waterline Length: 4.10m
Hull waterline beam: 0.22m
Beam: 2.41m
Draught: 0.25m
Air draught: 8.45m
Weight: 145kg
Mainsail area: 13.12sqm
Jib area: 4.38sqm
Upwind sail area: 17.5sqm
Build: GRP
Dart 18
In 1969, Ian Fraser & Kim Stephens became partners to build GRP Tornadoes under the Panthercraft trademark. In 1973, after a successful commercial and racing debut, they commissioned yacht designer Rodney March to design a new double-handed catamaran for series production, hoping for a similar success to the Laser. With the help of Terry Pearce & Keith Musto, they worked out a first prototype of the Dart 18 which was introduced at the Paris boatshow in January 1976. Two years later, 70 boats were entered in the European championships at Carnac in Southern Brittany.
Designed for a mixed crew, or singlehanded crew with only the mainsail, and without daggerboards, the Dart was designed as a performance compromise that is easy to handle, easy to rig and easy to trailer.
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Dart 18
Catamaran
Designer: Rodney March
Introduced: 1973
Length overall: 5.48m
Load Waterline Length: 5.01m
Hull waterline beam: 0.26m
Beam: 2.30m
Hull beam: 0.35m
Draught: 0.25m
Air draught: 8.56m
Weight: 130kg
Mainsail area: 12.92sqm
Jib area: 3.16sqm
Upwind sail area: 16.08sqm
Build: GRP
