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Mainsail
Sail rigged to the main mast of a sailing vessel / From Wikipedia, the free encyclopedia
For the MAchine INdependent implementation of the Stanford Artificial Intelligence Language, see SAIL (programming language).
A mainsail is a sail rigged on the main mast of a sailing vessel.[1]
- On a square rigged vessel, it is the lowest and largest sail on the main mast.
- On a fore-and-aft rigged vessel, it is the sail rigged aft of the main mast. The sail's foot is normally attached to a boom.[1] (In extremely heavy weather, the mainsail may be lowered, and a much smaller trysail hoisted in its place).
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Historical fore-and-aft rigs used a four-sided gaff rigged mainsail, sometimes setting a gaff topsail above it.
Whereas once the mainsail was typically the largest sail, today the mainsail may be smaller than the jib or genoa; Prout catamarans typically have a mainmast stepped further aft than in a standard sloop, so that the mainsail is much smaller than the foresail.[2]