Contur flexibility

Contur® – The intelligent propeller made of Carbon Fiber

A feature that was not originally recognized but which has proved to be extremely effective is the flexibility of the carbon fiber material used for the Contur® propeller blades. This propeller series was developed specifically for yachts and guarantees a high level of traveling comfort and performance during long voyages. The Contur-F® series propeller is the only propeller in the world, which adjusts its pitch automatically without external setting mechanisms. Based on comprehensive calculation models our engineers are able to define the material composition, which allows a predetermined deformation of the propeller blade as a result of the load applied by the water pressure.

The blade is no longer rigid and stiff, but flexible – we call it an “intelligent propeller”. A rigid propeller is rated for a specific operating point, usually maximum speed. At this point its pitch is optimal, it takes up the full power of the engine and reaches its maximum efficiency level. In contrastContour® Carbon Fiber Propeller, a flexible propeller deforms in operation, the pitch accurately adapts to the acting load. This means that the propeller has the optimum pitch across a wide operating range. The benefits to the yacht owner are: improved acceleration, increased fuel savings, and the smoothness of operation. The propeller behavior is essentially influenced by the yacht’s hull form. A deadwood or a broad keel disturbs the water flow past the propeller. Each time a propeller blades rotates through the “lee” side of the stern, the load is higher than the other blades. This is when cavitation can occur. Cavitation is a phenomenon, which is the result of high propeller loads, which create water-vapor bubbles on the blade surface. The bubbles implode “tearing off” minute material particles. The consequences will be damage to the propeller, vibrations and a high noise level. In contrast, the load acting on the Contur-F®propeller is reduced by the deformation of the blade. Cavitation can therefore be prevented or at least delayed.

The propeller runs much more smoothly and free of vibration, and its operating life is extended. Reducing the thickness of the blade tips results in a further increase in protection against cavitation. By using special surface materials, it is possible to triple the propeller’s resistance to cavitation and reduce the risk of damage due to cavitative corrosion.