As it was discussed in a previous post, an essential part of enhancing boat performance is optimising their weight. Mast and rigging design play an important role on managing the boat’s weight as well. The mast defines the supporting structure for the sail, and the rigging system helps the team to control the boat. It is important to analyse the main factors when choosing or designing these elements, so they will add value to performance. Mast and rigging design will be fundamental to the overall strategy of a team to increase their chance to win sailboat races.
Mast Weight and Materials
The weight that can be saved upstairs in a boat will be significantly reflected at the keel of the boat downstairs. In general, the more kilograms taken out of the boat, the faster it will go. Aluminium has been a material used for many years when building masts. The mast is selected from a series of designs and a team chooses that which fit is best for the boat. Aluminium is a hard and corrosion resistant material with a density of 2.7 g/cm3, which in small scales could be considered a light material, but in a larger scale like a mast can add a lot of weight.
Carbon fibre can greatly improve performance as it is lighter than aluminium, its density varies from 1.6 to 2.0 g/cm3. It can make the mast stronger in specific areas where better strength is needed.
As carbon composite is a light material that combines stiffness and strength where forestay tension can be considerably increase, giving an increase in upwind performance. Moreover, as the total weight is reduced, the yacht will sail faster. Two types of carbon fibre masts could be used: standard modulus material and high modulus material. The latter is more expensive but it’s even lighter. Choosing a high modulus material depends on the team and how they balance cost-benefit to enhance performance.
Rigging Materials and System
The rigging is an important element when sailing as it helps the boat to be kept under control and keep the sail stretched for maximum wind capacity.
The material that has been most commonly used in rigging is PBO (polybenzoxazole). PBO fibres have been basically established as the industry standard on grand prix race boats. PBO fibre carries properties such as high tensile strength and high thermal stability, making it one of the strongest synthetic fibres and a great choice for yacht rigging.
On the other hand, carbon can be used as a solid extrusion or as a flexible fibre. It is characterised by its resistance and stiffness. However, carbon parts have to be protected from UV radiation when parts are exposed to sunlight. Additionally, all metallic parts must be isolated as carbon fibres are conductors and sensitive to cathodic corrosion. When designing the geometry of the mast and rig, it is essential to take into account different parameters such as loads from the respective sail, all the relevant information related to the standing rigging and the mast tube geometry and material specifications, all of those design parameters most work together to make a good system. When everything is taken into account you can see a marked improvement in performance, and by optimising the rigging teams may be able to sail to victory.