In mid Seventies Intermarine, in the wake of its researches aimed to developing methods for building large GRP vessels, started developing a new concept of hull construction, which soon appeared to be sound for building those special vessels devoted to Mine Countermeasures operations.
This concept allowed to exploit at utmost the intrinsic elasticity and flexibility of GRP, and therefore to build vessels capable to withstand the shock caused by underwater explosions of mines by “absorbing” elastically the enormous energy released by the explosion.
This led to a peculiar and unique construction technique, known as “Monocoque Single-Skin without Reinforcements”, consisting in building the hull structure without any longitudinal nor transverse reinforcement, but with increased shell thickness for providing the necessary structural strength of the hull girder.
The practical implementation of this construction technique required Intermarine designers not only to have a much more active role in the engineering phase of the design process and to acquire an intimate knowledge of the features and performance of the various raw materials, but also to implement innovative and revolutionary outfitting solutions.
In Intermarine MCMVs the main engines and machinery are installed on cradles suspended between watertight bulkheads, such a solution allowing not only the proper functioning of the propulsion system under shock load but also providing additional benefits in terms of silent navigation and therefore higher safety for the vessel and the crew when navigating in the proximity of a minefield.
In addition to that, the liquid tanks are suspended between two watertight bulkheads and kept separated from the hull structure, (i.e. with a significant clearance from the hull bottom) so to avoid direct transmission of the shock to the internal structures when the hull elastically flex under shock loads.
Still today Intermarine is heavily investing in research and development in the field of the composite materials and of the associated construction techniques: during the years materials and technologies have been continuously refined and improved, keeping Intermarine on the leading edge of the Mine Countermeasure market.