A brave new warship is being built by a Hungarian enterprise in a shipyard in southern France. Only three such has been built globally so far. Learn more about the project Ocean Eagle.
The ship Ocean Eagle 43 is a trimaran consisting of three hulls, the advantage of which is that it is very fast and safe as well. This type of ship has been used till now typically for breaking various water speed records or applied in building very expensive extravagant luxury yachts.
The patrol boats have been built in southern France with the collaboration of a Hungarian firm, Pata-Megayacht ltd. The Hungarian company fabricated the complete hull out of composite materials as a subcontractor of H2X. The construction material of the trimaran is special: they are made of carbon-reinforced epoxy composites. This material and technology is typically used in aerospace, Formula-1, or, as mentioned, in building individually designed ships optimized for speed.
The main hull of the Ocean Eagle ships is 43 meters in length. A hull in such scale has never been made in a single piece, with vacuum-infusion technology out of carbon epoxy composite. The width of the ship exceeds 11 meters together with the two side hulls. The floating marvel has been born in H2X’s 10 thousand sq meters construction hall. Despite rapid developments in technology, fabrication of hulls still needs much live labour. The first major task was preparing the moulding tool, which is the negative copy of the actual form of the hull – explains Pata (Gábor Antal), owner and CEO of Pata-Megayacht ltd. This means that first the negative template of the hull has to be constructed in such strength that several hulls can be formed in it and can be removed from it.
Intelligent composite construction
The template is first designed by a CAD software. Then, the cross members of the template are cut out of plywood with a CNC mill at an accuracy of a millimeter. Finally, the frame of the template is assembled on which the cover surface of the template is built on this that would define the shape of the ship shell. Later, the epoxy-glass-fiber-carbon-XPS layers and reinforcements are laid on this, in the order defined by the design engineers.
This is followed by piping, that is, a vacuum and a resin inlet pipe system is laid on the covered frame. After airtight sealing the entire structure, vacuum is formed between the foil and the surface of the template in an infusion procedure. To the effect of this, the liquid epoxy resin flows into the system through the resin inlet pipes and soaks the shell materials already laid in full cross section. Having finished the infusion, the hull is kept in vacuum for at least 12 more hours.
It is vitally important that the shell material does not stay dry anywhere, because then the hull will not perform the designed and calculated strength and the ship or the given part has to be scrapped or repaired at a high cost – explains Gábor Antal, who helps in physical work if the need arises.
The vacuum-infusion process ends in an insulated heat-treating tent heated up to 60 degrees. Here, the hull achieves its final strength after a 16-hour-long hardening period.
Transport to northern France
The empty, structural weight of the hull weighs 27 tons, and there was less than 5 kg difference in the three delivered ships. If 10-15 people can work in the moulding template, the 43 meter-long hull is ready in approximately two months – explains Pata. A further three months is needed for the fabrication of the further main elements – such as the bridge with the steering post, the deck assembled from several elements, the supporting hulls and the wings that hold them – and the assembly of these components with the central hull. A total of 106 composite elements have to be assembled.
The bare hulls of Ocean Eagle 43 made by H2X are transported to the harbour of Cherbourg in northern France for final assembly. Here, drive mechanism and electronics are installed and the systems are fine-tuned. The maintenance and operation cost of Ocean Eagle is a fraction of that of non-composite ships, for example, because corrosion-related costs are approximately zero. Ocean Eagle is able to take the same distance at the same speed with a fifth of fuel consumption as opposed to single hull counterparts of the same class and function. „Lightweight construction is of key importance from the point of view of acceleration and long term fuel efficiency” – says Pierre Lallemand, head of composite division of H2X. Top speed of the ship is 30 knots (1 knot=1,852 km/hour).