Full-Displacement

When planning to embark on long distance journeys that will take the boat out longer than the usual overnight passage, there are several factors that needs to be considered. The same factors must also be considered for coastal cruising with limited number of passages. This is to ensure that the passagemaker is made to provide comfort for the crew and passengers while at the same time provide security to make the passage safe. Keep in mind that when a boat has been designed for coastal cruising only, it is not recommended to take it for long distance trips.

One of the important factors to consider is the efficiency of the full displacement hull. It must be designed to be fully in water no matter what the speed of the passagemaker might be. It will not raise-out of its bow wave and plane while on the surface of the water. A full-displacement hull also requires a fraction of the horsepower needed that a planing or a semi-displacement hull needs to reach optimum speed. A fill-displacement hull placed in a 40 feet to 120 feet boat will be able to maintain speeds in the 7 to 12-knot range while burning less fuel.

Above the said speeds, the boat with a full-displacement hull needs to be above the plane. A planing boat needs more horsepower and has different properties compared to a full-displacement model. Planing boat requires a lot of fuel and produces a lot of vibration and noise. That’s why it is recommended to consider a full-displacement hull for fuel efficiency when planning for long cruises.