Hull characteristics

Having defined the hull form it is possible to derive a number of characteristics which have significance in determining the general performance of the ship. As a floating body, a ship in equilibrium will displace its own weight of water. This is explained in more detail later. Thus the volume of the hull below the design load waterline must represent a weight of water equal to the weight of the ship at its designed load. This displacement, as it is called, can be defined as:


p = the density of the water in which the ship is floating g = the acceleration due to gravity V = the underwater volume.

It should be noted that displacement is a force and will be measured in newtons.

For flotation, stability, and hydrodynamic performance generally, it is this displacement, expressed either as a volume or a force, that is of interest. For rule purposes Lloyd's Register also use a moulded displacement which is the displacement within the moulded lines of the ship between perpendiculars.


It is useful to have a feel for the fineness of the hull form. This is provided by a number of form coefficients or coefficients of fineness. These are defined as follows, where V is the volume of displacement:

How To Have A Perfect Boating Experience

How To Have A Perfect Boating Experience

Lets start by identifying what exactly certain boats are. Sometimes the terminology can get lost on beginners, so well look at some of the most common boats and what theyre called. These boats are exactly what the name implies. They are meant to be used for fishing. Most fishing boats are powered by outboard motors, and many also have a trolling motor mounted on the bow. Bass boats can be made of aluminium or fibreglass.

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