Sheer (ship)

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Dimensions of a hull Ship's hull shape en.png
Dimensions of a hull
The prominent sheer in the bow of the battleship USS New Jersey USS New Jersey BB-62 Museum Camden.JPG
The prominent sheer in the bow of the battleship USS New Jersey

The sheer is a measure of longitudinal main deck curvature, in naval architecture. The sheer forward is usually twice that of sheer aft. Increases in the rise of the sheer forward and aft build volume into the hull, and in turn increase its buoyancy forward and aft, thereby keeping the ends from diving into an oncoming wave and slowing the ship. In the early days of sail, one discussed a hull's sheer in terms of how much "hang" it had. William Sutherland's The Ship-builders Assistant (1711) covers this information in more detail.

The practice of building sheer into a ship dates back to the era of small sailing ships. These vessels were built with the decks curving upwards at the bow and stern in order to increase stability by preventing the ship from pitching up and down. [1]

Sheer on exposed decks also makes a ship more seaworthy by raising the deck at fore and aft ends further from the water and by reducing the volume of water coming on deck.

See also

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This is a glossary of nautical terms; some remain current, while many date from the 17th to 19th centuries. See also Wiktionary's nautical terms, Category:Nautical terms, and Nautical metaphors in English. See the Further reading section for additional words and references.

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Well deck

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<i>Sparrow Hawk</i> (pinnace)

The Sparrow-Hawk was a 'small pinnace' similar to the full-rigged pinnace Virginia that sailed for the English Colonies in June 1626. She is the earliest ship to participate in the first decades of English settlement in the New World to have survived to the present day.

References

  1. Dawson, Philip (2005). The Liner . WW Norton & Company. ISBN   0-393-06166-3.