Terminology and Mechanics of Sailing
On to the mechanics and terminology of sailing. I will cover parts of the sail and sailer as well as wind direction, forces acting on the sail and craft, speed and directional control.
Sheet: The rope or line used to control the angle of attack of the sail. Also refers to the act of pulling in or releasing line, known as sheeting in or sheeting out.
Blocks: Also known as pulleys.
Boom: A rigid horizontal support running along the foot of the sail, from the foot to the clew or outhaul.
Mast: Vertical support for the sail, usually made of aluminum or fiberglass.
Parts of the sail:
Head: The top of the sail.
Leech: The unsupported upper trailing edge of the sail.
Foot: Lower edge of the sail.
Luff: Forward edge of the sail that is supported by the mast, on landsailers most commonly by a sleeve that slides over the mast. The luff is usually cut in a curve, so that a pocket is created in the area just behind the mast. This lends an airfoil shape to the sail, giving the sail lift to the side.
Batten: Flexible sail supports that slide into pockets sewn on the sail. These help maintain the airfoil shape, and keep the sail from flapping.
Clew: The outer attachment for the boom, where the leech and foot meet.
Downhaul: The lower attachment point, where the luff and foot meet. The forward end of the boom also attaches here. Also refers to the act of pulling down on the foot of the sail.
True wind: the direction the wind is actually blowing.
Apparent wind: the wind the sail and sailer feel; the angle of the apparent wind changes as the craft gains speed (it will make more sense in a bit).
Upwind: also known as into the wind. Usually refers to a course heading.
Bear up: Turn upwind
Downwind: also known as off the wind.
Bear off: Turn downwind.
Tack: make a turn upwind, with the sail passing from one side to the other.
Jibe: make a turn downwind.
Hike: getting the upwind wheel off the ground