Catana Construction

Thirty years of research and sailing experience has provided CATANA the image of unrivalled seaworthiness and a legendary reputation for building a solid, comfortable high performance catamaran. Millions of miles covered by hundreds of our customers, together with the dynamic team at CATANA, ensures we capitalize on every available piece of knowledge to offer you the very best catamaran for long-distance cruising.

Carbon Infusion – Explained

Construction by infusion and the use of carbon fibre are now standard at Catana. The drawing office of the Catana shipyard has carried out an in-depth analysis to identify the areas where the utilisation of carbon would allow substantial weight savings.

Carbon fibre is far more stiff than glass fibre. It allows one to reduce the layers of fibre used in construction. This in turn translates into weight saving. The areas where there are only 1 or 2 layers of glass fibre obviously cannot be replaced by no layers or 1 layer of carbon. But in areas where we have 10 layers of glass fibre, we can replace them with 6 layers of carbon for example. It is specifically in these areas that we now save a lot of weight in resin.

Thus on a Catana, the coach-roof, all of the structural bulkheads, the omegas, the chain-plate reinforcements and other reinforcements are carbon.

Twaron® – An Understanding

The choice of using Twaron® for the sandwich construction is obvious. The fibre is 10 times more resistant to puncturing and 3 times more resistant to traction than classic glass fibre. Twaron® is also half the density. The weight saving and rigidity provide a CATANA with more comfort, without any loss of their legendary performance.

Twaron® is a very strong, light para-aramid fibre (poly-paraphenylene terephthalamide) developed and produced exclusively by Teijin Aramid. It has a high modulus, is thermally stable and highly impact and chemical resistant. Since its development in the 1960s and 1970s, Teijin Aramid is producing the monomer and polymer in Delfzijl and the yarn in Emmen (The Netherlands). Twaron® is used in a huge range of specialist applications, specifically customized to complement customers’ products, and is widely recognized by many industries as a quality product with great durability and recycling potential.

Main characteristics:

  • High tensile strength – strong and light: weight for weight, Twaron® is 5 times stronger than steel.
  • Fatigue resistance – little loss of strength during repeated abrasion, flexing and stretching.
  • Dimensional stability – stiff and highly oriented molecular structure leads to a high modulus of elasticity, low creep and low stress relaxation. Low thermal shrinkage, i.e., excellent dimensional stability.

Twaron® Impact Process

Twaron® Impact is a construction process which mixes rigidity, lightness, and mechanical resistance, owing to a top-of-the-line, high resistant fibre. Twaron® is used in the manufacture of military helmets, bullet-proof vests, and the aviation industry. It is several times more resistant than glass fibre and is particularly resistant to breaking under tension, scratching and collision.

The exclusive Twaron® impact construction process uses vinylester resin having the same mechanical properties as epoxy, but without its disadvantages in application or further repair. The boat’s total unsinkability and the enormous strength of the Twaron® Impact structure, mean that a Catana can face the most difficult seas in greater safety than any other boat available today, whether a monohull or classic catamaran.

Furniture: All In Sandwich

The Catana have an unrivaled finish. It’s a well-know fact – and it shows. What you cannot see is that all that beautiful wood and fine cabinet work do not weigh down the boat. All the materials used for the boat’s furniture; the cabin sole, liners and ceilings, have an extremely low density, less than one. The whole joinery is made of foam-cored sandwich, finely veneered. This combines aesthetics, stiffness, solidity and light weight. The elegant interior of your Catana weighs several hundred kilos less than that of a classic boat.

Catana boats are built entirely of sandwich construction under vacuum. For a catamaran where each hull sails over different waves, its strength and long life depend on the rigidity and consistency of the boat’s structure. The core of the hulls and bulkheads is made from PVC foam, with density of 75 kg/m3 and a minimum thickness of 20mm. The core of the decks, platform and coach-roof is made with foam up to 40mm thick.

The Structure Integrity

Twenty-one structural bulkheads ensure the rigidity and long life of a Catana. The bulkheads are all of sandwich construction and reinforced with carbon fibre on both sides, fully laminated to the hulls, the deck, the coach-roof, the cockpit, and all the surrounding structures. The hull & deck joint is glued and completely laminated with several bi-axial materials.

The hull and deck of a Catana are as solid as though they were cast in one piece. A Catana will keep its shape with exceptional rigidity, not only because it is totally of sandwich construction, but also because it is reinforced by a uni-directional material which bears all the strain of bending and twisting. This method of construction guarantees an outstanding strength and lifespan.

Sailing Performance – Daggerboards

Without good keels or daggerboards, a catamaran is unable to sail well upwind. However, with its daggerboards down, a Catana can sail upwind like the best monohulls, and even faster. Downwind, daggerboards up, the resistance in the water is less far, thus a Catana increases its speed without any efforts on the structure. One additional advantage of daggerboards is the very shallow draft, enabling the Catana to moor in very shallow areas of water, up river and even drying out on the bottom in suitable locations. Great for fun, great for safety and great for mooring up in those protected shallow areas in beautifully secluded lagoons.

As with the wings of certain airplanes, the daggerboards of a Catana are geometrically changeable. When the wind strengthens, the helmsman slowly lifts the daggerboards as their pressure on the water increases with the square speed of the boat. The sabre-shaped daggerboards are laminated with uni-directional reinforcements. The daggerboard casings are totally waterproof and joined to the hulls in such a way that they have been deemed indestructible. They are carefully fixed to the hulls by ribs and braces whereby the strain is taken along the whole length of the planking and at the bottom of the hull. Finally, a gusset brace aft, guarantees that any violent impact will damage the daggerboard itself but leave its casing and the bottom of the hull intact.

The Hulls

The elongated, torpedo-shaped hulls lessen the ‘rocking chair’ effect in heavy seas. The Catana hulls create less drag than that of a normal wide-hulled catamaran. Boat speed is therefore higher for the same sail area or equivalent engine power. The aerodynamic shape of the coach-roof reduces windage, as well as being more aesthetically pleasing. The volumes at both ends of a Catana hull are important, making them more resistant to pitching in the swell.

Aeronautical Techniques

To build a fast catamaran with exceptional comfort for luxury cruising is more difficult; something of a challenge. Yet, Catana has taken up this challenge with gusto characterized by the incessant chase for superfluous weight. A ‘diet plan’ applied at all levels resulted in a Catana 50 lightened by 3000 kg; the infusion process (hulls, deck, bulkheads, bimini – resulted in saving 1300kg); new lighter bimini (-300kg); aluminum forward crossbeam lighter than a composite beam (-380 kg, includes the removal of the catwalk). Or the removal of the fifth bulkhead further to two studies conducted by two specialized engineering firms to verify the decision. The decisions that guide Catana – maintaining a course for excellence: the search for comfort, pleasure, and the ultimate coupling of speed and safety.

From the thickness of joinery (a saving of 120kg) to the limitation of excessive use of certain products, to the design study done on the elongation of the hulls in the shape of torpedoes which dampens the ‘rocking chair’ effect in a seaway. This is all part of the new thinking which has gone into this qualitative effort with as a highlight the introduction of variable geometry dagger-boards: when the wind strengthens, the helmsman progressively raises the dagger-boards. This series of innovations has in no way compromised Catana’s legendary hull strength. Solidity and quality remain guaranteed by the care and perfectionism of our teams in the building process.

Catana catamarans are built entirely in vacuum sandwich. For a cat whose two hulls sail on different waves, the strength of the hull and its longevity depends on the stiffness of the structure and its homogeneity. The hull and bulkhead core is made ofa PVC foam of 75kg/m3 density and 20mm minimum thickness. The deck, bridgedeck and coach-roof core are also foam core to 40mm thickness. The core is reinforced in the bows by a layer of Aramid UD multi-axial Twaron®.

A company ready to take on an evolving market; the restructuring of the group is completed. The result is a complete brand line and two high performance production sites. One in Marans, in Charente Maritime, and the other at Canet-en-Roussillon. The Poncin Group has positive cash flow this year, a unfailing sign that there are orders and that the restructuring of the group has born its fruits.

The introduction of the new Catana 47, while waiting for the new 59 in 2011, enriches a recent and already thoroughly renewed product line. The efforts made by Catana at the high-end and in high-tech, associated with successful sales initiatives overseas, has allowed the yard to substantially increase its activity with high value- add orders.

The new production site (the factory at Marans) specialized in the manufacture of composites in Charente Maritime, but now welcomes the construction of the Catana 42.

Weight Saving – The Advantages

Because of the weight saved by using these techniques, a cruising boat can carry more water, fuel, and equipment without effecting its handling or comfort in heavy seas – its’ performance is optimized. The aramid fibre used throughout the interior skin of the sandwich is 10 times more resistant to puncturing and 3 times to tension than classic glass fibre. Even in the case of hitting a significant floating object, you will be able to continue your journey… Especially because the absorption of the shock wave by the foam increases your safety.