In light of the recent passing of pioneering multihull designer James Wharram, we share his Practical Boat Owner article from our October 1994 issue, published for the first time online.
In 1993 James Wharram and his family adopted the life-style of Polynesian migrants on board their double canoe Spirit of Gaia.
They voyaged 6,000 miles, experienced dozens of adventures and discovered why those intrepid Pacific explorers worshipped their boats as Gods.
An article by James Wharram.
The BBC’s acclaimed series Nomads of the Wind, was the fantastic story of the Polynesian migrations and subsequent island discoveries across thousands of miles of Pacific Ocean aboard sea-going double canoes.
These double canoe raft ships were known to have been developed for offshore sailing 2,000 years ago.
A direct descendant of these craft are the present day catamarans.
Can we compare the sailing ability of the modern catamaran to the ancient double canoe vessels of the Polynesians?
Can we present-day sailors and designers learn anything from one of Man’s great ethnic ship designs of history?
I think we can.
In 1993 I lived as a ‘Nomad of the Wind‘ aboard our 63ft ethnic proportioned Double Canoe, the Spirit of Gaia.
We made a voyage of 6,000 miles, sailing from landfall to landfall: Falmouth, North Spain, South Portugal, and from island group to island group: the Canaries, the Madeiras, the Baleares (in the Mediterranean), a voyage of many adventures, that stimulated new ideas and gave us insights into the minds of Polynesians.
There was the memorable voyage, 500 miles from Gran Canaria to Funchal on Maderia, when, with the rudders lashed, in light winds, the Double Canoe glided across the ocean.
For a while, we left this century and the western world to become a part of the Polynesian sea world.
Turtles in the sea, dolphins around, sea birds flying in the sunset, and the nights lit with brilliant stars.
We loved our ship.
Poetry of the sea
Throughout history seafaring races have been poetical about their seafaring craft.
But you can only be in love with a ship that returns affection in sailing ability.
It could be the ability to point into the wind, so that you can reach a sheltering bay or harbour that lies upwind; it may be that the sails are easily handled in a squall; its motion may feel like a dance over the waves or it may have the lift and buoyancy to ride out storms.
Maybe it has a sense of power in reserve for that emergency, when you need to push the boat harder without incurring damage to the craft.
Sea-people learn to trust their subjective and instinctive boat feeling, that their craft is in tune with nature.
The Spirit of Gaia is such a ship.
To satisfy the Western analysing part of our nature, we fitted the Spirit of Gaia with Brookes and Gatehouse “Focus” instruments for recording true and apparent wind angles, windspeed and a sensitive log for speed through the water.
In addition we carried a Sony GPS for point position finding.
Some yachting magazines print boat performance in a diagram called a polar curve, which combines three facts: True wind speed, true wind angle and boat speed, but to get a better picture of how the boat sails, you need more information: apparent wind angles, sail area carried related to the stability of the vessel (most important for multihulls) and speed/length ratios to compare the results with other boats.
Hanneke, my design partner, chief mate on the Spirit of Gaia, has drawn the Gaia’s sailing performance in wind force 5-7 (see figure 1) giving all this additional information and, for those interested in the finer points of sailing, the contain much to study.
The Polynesian ethnic proportioned Spirit of Gaia can sail with her schooner rig 45º off the true wind, can cruise in force 4 (11-16 knots) winds at average speeds of 10 knots, which is a speed/length ratio of almost 1.5√WLL, (WLL being the waterline length) equivalent to the top average which a monohull racer, hard driven over on her ear, can be expected to achieve.
Pushed a little harder, she sails at 14-16 knots, which equals 2.2√WLL.
Note, at this speed her stability of 56 knots!
Many people fear fast catamarans as they are known to capsize.
Festive feel on the helm
The joy of sailing the Spirit of Gaia at an easy 10 knots was best summed up by an Austrian sailor, who, after four hours at the wheel, when offered a relief, declined, saying:
“This is like Christmas all the time.”
To sail with ease, upright and with little structural stress at speeds proportional to the Clipper Ships and hard-driven modern Ocean Racers, in wind strength of only 13-15 knots (force 4) does demonstrate the design genius of the ancient Polynesian Double Canoes.
A student of the pre-European Polynesian Double Canoe designs could point out:
“Your Spirit of Gaia may have Polynesian hull shapes, rounded V hulls and waterline/length ratios of 17:1, but she is different in certain aspects of design from an ethnic Polynesian Double Canoes.
“You have improved on the basic concept with modern design concepts, for the Spirit of Gaia has the wide overall beam and the large sail area/displacement ratio of a modern multihull, using advanced sail design with sails made of modern Terylene.
“The Polynesian sails were made of ‘matting’.”
This is all true, and, using the hulls of the existing Spirit of Gaia, Hanneke has drawn out a more ethnic Polynesian Double Canoe (see figure 2).
In reverence to the Spirit of Gaia’s Hawaiian name, given to her by her Hawaiian launching crew, who came to Cornwall specifically for the occasion, we will refer to this craft as the Makua Hine Honua.
At first glance, the diagram suggests a very narrow beamed catamaran with peculiar shaped sails of moderate area and a deep paddle for steering and another for leeway prevention.
Can such a craft compare in speed and seagoing ability with a modern performance catamaran?
Let us look in more detail at the possibilities.
The prime factor in design of cruising catamaran speed and sea-going ability is sufficient stability, for without it, you have an upside down catamaran.
The ‘narrow beamed’ (by modern standards) Makua Hine Honua with her low rig has a calculated static stability of 28 knots!
This means, under full sail, it would take a gale of 28 knots to capsize her (though, to allow for wind gusts, ie dynamic stability, it would be advisable to consider reefing at 23 knots of wind).
Many of the wide-beamed, modern, performance, cruising catamarans on the market, to which the Makua Hine Honua is compared, have a static stability as low as 25-27 knots.
This means, if you do not stand by the sheets at wind speeds of force 4 prepared for instant release, in a wind gust, there is a risk of sudden capsize.
Nobody is quite certain why Polynesian Catamarans had, in relation to the modern catamarans, a narrow overall beam, though we can see, that it did not affect stability.
For years I thought it was for greater manoeuvrability when under power (ie paddle power).
Now I am beginning to suspect that the Polynesians were as advanced in hull dynamics as they were in the aerodynamics of sail design.
Perhaps the interacting bow waves, through their narrow hull separation, provide close to the bows a hydro-dynamic lift against pitchpoling – a problem of some modern catamarans.
The sail rig on the Makua Hine Honua does look like the modern Bermudan sail rig set upside down.
C. A. Marchaj, a leading theoretician on aero and fluid dynamics of yacht design, did tunnel testing of Polynesian sail shapes, and found that close hauled at a true wind angle of 40º the Polynesian sail gave 5% less drive than the modern “High Performance” Bermudan mainsail and jib.
However, free the Polynesian sail off to wind angles of 50º-60º on the beam, and this sail shape gives 5-10% more drive than the Bermudan mainsail and jib.
The Polynesian sails of old were made of matting but not the type of matting you may have on your kitchen floor.
Generations of Polynesians had developed a tough, finger-woven “fabric” from finely split tensile Pandanus palm leaves.
It was a most effective windward material.
The rig shown on the Makua Hine Honua with modern theory and experiments in wind tunnels in its favour can be regarded as an efficient, high pointing windward rig.
The original Polynesians lived and sailed in the trade wind areas, where for most of the time winds blow between force 4-7.
The Polynesians did not need large sail areas.
In winds of force 4 upwards, the moderate 800 square feet Polynesian rig of the Makua Hine Honua would power her on a close reach (55º-60º off the wind) between 150-250 miles in a 24 hour period.
So, with light overall weight (we calculated her weight at 7 tons in traditional materials), plus high stability, efficient windward sails mounted on an efficient windward hull form, the Makua Hine Honua of antiquity is, by present day analysis, an efficient sailing machine.
In fact, the oldest, (by 2,000 years), earliest double-hulled craft is a basic point of reference by which to judge subsequent double-hulled sailing craft.
With reference to the Spirit of Gaia, I have written “We loved our ship.”
Well, the Polynesians worshipped theirs.
Article continues below…
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‘Go faster’ lines
The double canoe and sailing the oceans was at the heart of their religious beliefs and social customs and attitudes.
According to the early European sailors, the finish and decoration of their ships “was of the highest standards.”
Polynesian hulls were a vivid polished black, red or yellow colour.
They were decorated at bows and sterns by highly elaborate, sacred carvings and had what we might call ‘go faster’ lines – not in paint but glittering inlays of mother of pearl shell, or, in some observed examples, sacred bird feathers, usually coloured red, fixed in a shimmering band around the hulls, just below the gunwales.
Heading upwind, swooping across the tradewind seas, such craft could easily sail distances between 1,500 to 2,000 miles in 10 days.
If they found no new land, they could easily turn around and run with the wind home.
Returning ships like these were described by the early Europeans as riding through the passes in the reefs at high speed towards the beaches.
Streamers from the sails were flying in the wind, people singing, drums beating, conch-shells blowing and naked girls dancing on the high bow and stern platforms.
For sailing in colder northern latitudes, as we did a western cruising catamaran designer needs to add some creature comforts to the basic Polynesian sailing machine:
- Weather shelter
- Private toilet facilities
- Private sleeping places with double bunks
- A communal dining table
In the first 25 years of western cruising catamaran development from 1960 to 1985, designers did succeed in developing catamarans with speeds of equal and above the fast monohulls, that provided sufficient weather shelter, western privacy standards, a fixed table with seats around, and most important, a high degree of static stability against capsize, at moderate cost unit.
Around 1985 a new trend in western catamaran development began.
This design trend encompasses the “Modern Performance Catamaran”.
It is hard to remember in the financially stringent 1990s, how the mid-1980s was a time of large amounts of surplus wealth, known as the ‘Yuppy Era’.
The non-heeling, wide beam of the raft-like catamaran provides a superb base for luxurious, spacious accommodation.
In theory, it only needed to join this accommodation to the high speeds of the ocean racing catamaran of the mid-1980s, and you had, for the requirements of the ‘Yuppy era’, an excellent package for marketing purposes.
A cruiser incorporating speed, high-tech and luxury.
Five star luxury
New designers came forward to develop this package.
They looked to computer technology for design inspiration, rather than to nature and man’s sailing history.
The Polynesians, if these people had ever heard of them, had no relevance at all to the modern catamaran design.
With computer-aided design they set out to optimise every aspect of the previous designed western catamaran: freeboard, internal volume, overall beam, mast height, sail area.
This optimised package was then styled, internally to the luxury of a five star hotel suite and externally to car and powerboat styling concepts to imply speed.
How far these new designs diverged in design aspects from the ethnic proportioned catamaran can be seen in the bottom of the graphic.
The shaded catamaran is a composite of five ‘modern performance’ catamarans.
Easily combined, they had remarkably similar freeboard, mast height and sail area proportions.
The modern performance catamaran has everything a modern, wealthy, soft, urban commuter could wish for.
For every two crew members there is an ensuite toilet and shower.
That means four toilets to eight people.
Double beds five feet wide (though I have notices that they often lack the ergonomics for a varied sex life).
They have water desalinators, washing machines, microwave ovens, deep freezers, quality stereos, television, electronic instruments to aeroplane cockpit display standards and so on.
In these aspects, they are certainly ‘modern.’
But how do they measure-up when it comes to performance.
Indeed, what is meant by the word performance?
It is a very slippery word.
It is a modern advertising word and means different things to people of different attitudes.
To myself and many designers, it is always used together with other words, like performance in relation ‘to’.
The practical proven windward performance of the Spirit of Gaia is 45º off the true wind.
The theoretical windward performance of the ‘High Performance Bermudan Racing Rig’, as used on the composite ‘Modern Performance Catamaran’, is 3-5º closer to the wind, ie 40º off the true wind.
The Spirit of Gaia rig costs £11,000; the shown Bermudan rig was worked out at approximately £50,000.
So, in order to achieve a theoretical ability to sail 5º closer to the wind, you have to spend £40,000 more.
In cost efficiency, the shown Bermudan rig has very poor ‘performance’.
In stability values, the shown Bermudan rig has also poor performance.
The composite ‘Performance Catamaran’ with his high heeling rig, for safety in wind gusts, would need to be reefed at force5, whereas the narrow beamed Double Canoe Makua Hine Honua only needs reefing at force 6. (So does the Spirit of Gaia).
The high profile (so high, they were last used in sailing ships of the 16th and 17th century) of the composite craft, will reduce windward performance in winds above force 5 to the point where engines become a vital component of the windward performance.
That is the reason, why the manufacturers of modern performance catamarans, always stress the power and quality of their engines when it comes to the hard sell.
(The 63ft Spirit of Gaia has two 9.9hp, four stroke Yamaha outboards).
The Polynesian Double Canoe is a product of evolutionary design logic for a fast craft using the minimum of materials and resources to sail the seas.
The modern performance catamaran is a consumer product which has evolved over a relatively short time period and is suitable only for a limited number of people.
It was mainly due to the high advertising budgets of the late 1980s, that the modern performance catamaran was projected as ‘state of the art’ in the cruising catamaran development.
In the more financially stringent 1990s, the numerical market base of wealthy yacht owners has narrowed considerably.
Can the present day ‘modern’ cruising catamaran concept survive on such a narrow market base?
What the ancient Polynesian Double Canoe designers have sown through the Spirit of Gaia is an opening into a ‘Post Modern’ school of catamaran design, that can move forward in the financially stringent 1990s, using the logical design principles of the Polynesian Double Canoe, improving its lack of accommodation and weather shelter within the constraints of evolutionary developed sailing ship design.
It makes sense never to forget: cruising is more than hard efficiency or wealth display.
It is about the joy of sailing and companionship.
I remember a night in a quiet Mallorcan anchorage, sitting on deck, with our mixed crew of Japanese Shige, Canary Islander Sergio, and four exotic Spanish Catalan women, the fire flickering in the central deck fire-pit, stars overhead, the crew began to beat drums, tapping together pieces of fire log and clicking stones into a hypnotic primitive rhythm.
Someone began to blow the conche shell.
From the aft cabin pod, the call was sung into the night: ‘Makua Hine Honua‘.
Shige began to dance a primitive Okinawan dance.
Then, one of the Catalan women, dressed only in a sarong, stood up and also began to dance.
Her long hair swinging in a cloud around her, she approached me and drew me into her dance.
By the time you read this article, Shige, the Japanese, Sergio the Canary Islander, Dora, the Catalan, Hanneke, the Dutch, Ruther, the German, my son Jamie and me, the sea-gods willing, will be heading across the ocean on Spirit of Gaia, swimming and communicating with the dolphins, so much revered by the Polynesians.