primary sail

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July 13, 2026

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The mainsail is the principal sail on a ship's mainmast. Sails, in general, are pieces of fabric used to harness wind power for propelling watercraft. Early sails were made from animal skins or woven reed mats, with cloth sails appearing in ancient Egyptian art.12

Modern sails are typically made from synthetic materials like Dacron, which offer superior strength and shape retention compared to older materials such as cotton, flax, or hemp. The manufacturing process involves careful measurement, cutting, and sewing of the fabric, with reinforcements added at stress points. Sails are categorized as primary or secondary, with primary sails providing the main propulsion in normal conditions. Examples of primary sails include square sails, gaff sails, and jib-headed sails.2

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sail
Primary sails are those that supply the chief propelling force in ordinary weather; secondary sails are those that aid the primary sails either by helping to balance the ship or by providing additional driving power. There are six classes of primary sales: square sails, gaff…
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Primary sails are those that supply the chief propelling force in ordinary weather; secondary sails are those that aid the primary sails either by helping to balance the ship or by providing additional driving power. There are six classes of primary sales: square sails, gaff…
Read More