Forward section flare above water

Shipowners' requirements often lead to a pronounced forward section flare above water, e.g.:

Figure 2.6 Extreme U and V section forms in the fore part of the ship (Gothenburg comparative models)

Figure 2.7 Typical resistance characteristics of U and V forms in forward sections without bulbous bow (all resistance curves intersect at two points)

1. Where there are containers on deck in the fore part of the ship.

2. Where portal crane tracks are fitted up to the forward hatch.

3. On car and train ferries where there must be a minimum entry width near to the CWL within a limited distance abaft the stem.

Increased forward section flare has these advantages and disadvantages compared to reduced flare:

+ It deflects green seas.

+ It increases the local reserve of buoyancy.

+ It reduces the pitching amplitude.

+ It increases the height of the righting arm curve.

— It can produce water spray.

— More structural material is required.

— It may lead to large pitching accelerations and impacts.

Increasing the section flare above water to raise the righting arm curve can produce good results both fore and aft. In cargo ships the forecastle sides can be flared to an angle of 40°.

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