Beams in WingFoX Nano.

When designing the WingFoX Nano our main priority was maximization of the speed it reaches, so again a battle began for platform rigidity while maintaining its minimum weight.

And it was precisely here that our experience gained in constructing the masts began to bear fruit. We designed completely new beams which are characterized by a variable cross-section profile depending on the forces which impact upon them.

Although the front beam does not differ in its outer shape from the rear one, each of them is an entirely different construction. The array and number of carbon fibres, i.e. the laminating plan, is different for each of the beams since they both carry different loads. Needless to say, they are made of carbon prepreg and annealed in an autoclave at high pressure.

In spite of the variable cross-section of a beam which suits the specific stress pattern, when developed its surface makes a rectangle, which permits applying continuous unidirectional fibres along the entire beam.

This has a crucial effect on its crosswise rigidity. For comparison, the tenacity for carbon fibres ranges from 2700 to 3500 MPa while the ultimate elongation is from 0,6 to 1,4 %, respectively. For a typical EP resin the tenacity is approx. 80 Mpa with ultimate elongation 5 % (1 Mpa = 1 N/mm2). Therefore, it is of absolute importance to have the forces transferred directly by the carbon fibres and not by the resin.

Another important element is the initial stress of the carbon fibres before polymerization of the resin. The high temperature annealing of the carbon prepreg in a special mould in an autoclave guarantees appropriate initial stress of the fibres. Due to this technology as well as the variable cross-section of the beam, we have achieved a much higher rigidity than it would be possible with a circular beam cross-section and a traditional mould.

The lack of a dolphin striker in the WingFoX Nano seems obvious.

In order to effectively maximize the rigidity and strength one must know thoroughly the properties of materials already at the design stage. There is no provision for hiding air bubbles and other imperfections under a thick layer of topcoat as it is often the case when traditional technology is applied.

The appropriate shape of the beams permits their ends to hide completely in the hulls while at the same time the beams are carried well above the waterline. The deep and total mounting of the beams in the hull maximizes the rigidity of the entire platform.