Sergio Abrami, Yacht Designer at Sergio Abrami & C

As a specialist in advanced composites, Sergio Abrami created hulls and “safety cells” for Class 1 and X-Cat offshore boats. He is a technical and safety officer at UIM (International Powerboating Federation) and a lecturer at the Politecnico di Milano’s Master’s degree in Yacht Design and in other Italian yacht design schools.

JEC Composites Magazine: From your first boat, the LIMIT-TCI (1972), a GFRP “pocket” cruiser boat, to submarine components for the Italian Navy, how have composite materials developed and diversified?
Sergio Abrami: “The first great revolution dates back to the early 70s, with the advent of sandwich structures to replace simple planking structures in traditional wooden constructions. A sandwich structure is made up of two composite skins (GFRP/CFRP) with a light material core (balsa, expanded PVC, etc.) in the centre.

Sandwich structures revolutionized marine construction as they dramatically reduced weight, noise transmission, working hours and emissions. The following steps were the use of aramid fibres and then, during the past 20 years, the massive advent of carbon fibre. Above all, the types of reinforcements changed, but resins also evolved, from polyesters to epoxies, as well as vinyl esters. These topics should be studied in depth, suffice here to say that this evolution is already indicative of an industry who always looks ahead in research.”

JEC Composites Magazine: You have a direct experience with shipyards. Who are the different players contributing to all the activities related to boat building?
Sergio Abrami: “My experience mainly relates to small shipyards, and occasionally large ones. Working with small shipyards means that the client-designer-builder triangle has very short sides. This means great responsibilities for the designer, but very quick decisions.

In large structures, there are several filters, therefore production times are often longer, despite the greater workforce available. For the Fincantieri shipyard (the largest in Italy), I have been in charge of the executive design (detailed design, lamination and dimensioning) of large cruise ship superstructures, composite radar masts for fast ferries and cruise ships (Disney, Princesse series, etc.). For Fincantieri DCM’s military division, I carried out the composite sizing of hydrodynamic appendages for ships such as the Cavour and Trieste, superstructures for the Sauro IV series SMGs and other strategic composite parts built by Fincantieri for CN Navantia.”

JEC Composites Magazine: You are a UIM technical and safety officer. How has research in offshore powerboating improved performance and safety in leisure boats?
Sergio Abrami: “Thank you for the good question that allows me, even if in a quick and superficial way, to make known how much the offshore sporting activity governed by the UIM (Union Internationale Motonautique, the international powerboating federation) does in favour of safety in the world of pleasure craft.”

JEC Composites Magazine: How have powerboat competitions contributed to improving safety in pleasure craft?
Sergio Abrami: “I will try to summarize, starting from the most obvious topic: hull construction. Lightness and structural strength are essential to achieve speed and safety. The advent of the latest generation of materials in the past years means that racing boats, even damaged, never sink. These new materials make it possible to create, if well designed, light and strong survival cells.

Another know-how transfer is related to hull structures. We have gone from predominantly transversal structures, characteristic of traditional constructions, to constructions with a predominantly longitudinal structure first and then a sandwich one.

The use of high-modulus fibres is another “transfer” from the world of competition to that of pleasure craft, also due to the lower cost per kilo of carbon fibres.

Obviously “carbon” is not a magic word. You need to know how to design structures, size them correctly, therefore the mere presence of carbon does not exorcise dramatic breakages, quite the contrary! I have seen too many splendid creations (in terms of craftsmanship) be deficient from a structural point of view.”