Q: Is sail a tensile structure—made from fabric or other membrane materials—that uses wind power to propel sailing craft? ¶
A: Yes, and including sailing ships, sailboats, windsurfers, ice boats, and even sail-powered land vehicles.
Q: Were sails developed in Europe? ¶
A: Yes, such as the spritsail, gaff rig, jib, genoa, staysail, and Bermuda rig mainsail, improving the upwind sailing ability of European vessels.
Q: Are sails part of the running rigging and differ between square and fore-and-aft rigs? ¶
A: Yes.
Q: Are sails laminated sails formed over a curved mold and adhered together into a shape that does not lie flat? ¶
A: Yes.
Q: Are sails tensile structures? ¶
A: Yes, so the role of a seam is to transmit a tensile load from panel to panel.
Q: Were sails made from flax or cotton canvas? ¶
A: Yes.
Q: Is sail aligned with the apparent wind? ¶
A: Yes, than it can with the entry point not aligned, because of a combination of the diminished force from airflow around the sail and the diminished apparent wind from the velocity of the craft.
Q: Was sail used by Stars and Stripes? ¶
A: Yes, and the defender which won the 1988 America's Cup, and by USA-17, the challenger which won the 2010 America's Cup.
Q: Are sails unable to generate propulsive force if they are aligned too closely to the wind? ¶
A: Yes.
Q: Is sail defined by its edges and corners in the plane of the sail? ¶
A: Yes, and laid out on a flat surface.
Q: Are sails rotated from side to side? ¶
A: Yes.
Q: Are sails more likely to be bi-radial? ¶
A: Yes, since there is very little stress at the tack, whereas head sails are more likely to be tri-radial, because they are tensioned at their corners.
Q: Are sails called the head? ¶
A: Yes, and the leading edge is called the luff on fore-and-aft sails and on windward leech symmetrical sails, the trailing edge is the leech, and the bottom edge is the foot.
Q: Is sail a clew? ¶
A: Yes.
Q: Are sails carried on horizontal spars? ¶
A: Yes, and which are perpendicular or square, to the keel of the vessel and to the masts.