Stem profile

The 'normal' bow developed from the bow with vertical stem. The vertical straight stem was first used in 1840 in the United States, from where the idea quickly spread to other parts of the world. This form remained the conventional one until into the 1930s, since when it has become more raked both above and below the water. The 'dead wood' cut away reduces the resistance. The 'Maier form' used in the 1930s utilized this effect in conjunction with V sections to reduce frictional resistance (Fig. 2.4).

Figure 2.4 Various bulbless bow forms.--Conventional form;---Maier bow of

1930s;------Vertical stem, in use from mid-nineteenth century to around 1930

Figure 2.4 Various bulbless bow forms.--Conventional form;---Maier bow of

1930s;------Vertical stem, in use from mid-nineteenth century to around 1930

38 Ship Design for Efficiency and Economy

Stems more or less raked above water offered the following advantages:

1. Water-deflecting effect.

2. Increase in reserve buoyancy.

3. Greater protection in collisions. Damage above water only more likely for both ships.

4. More attractive aesthetically (particularly when stem line is concave).

Stems with reduced rake are still used where the 'overall length' is restricted, especially on inland vessels.

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