Welcome to You Ask Andy

Ron Libby, age 13, of Dodge City, Kan., for his question:

HOW DOES A BOAT'S SAIL WORK?

A boat's sail has curved edges so it will be shaped like the wing of an airplane when the wind fills it out. The side of the sail to the leeward (the "leeward" side being in the direction toward which the wind blows) corresponds to the top of an airplane wing. The action of the wind blowing across this curved surface creates a lift similar to the force that enables an airplane to stay in the air.

In a sailboat, this lifting force becomes a pull away from the sail toward the bow or front of the boat. At the same time, the wind also exerts a push against the other side of the sail.

In this way, the action of the wind on the sail combines in two ways to force the boat forward. These forces make it possible to sail a boat in almost any direction, no matter which way the wind is blowing.

There are three basic sailing maneuvers: sailing into the wind, sailing across the wind and sailing with the wind.

Sailing with the wind is called "sailing before the wind" or "running." In running, the sail is simply pushed along by the wind and makes its own resistance at the same time. To sail with the wind, of course, requires the wind to be blowing in the direction you want to travel.

Sailing into the wind is called "tracking to windward," "sailing on the wind" or "beating to windward." A boat can sail upwind by tracking, or following a zigzag course. In general, a sailboat can head to within 45 degrees of the direction from which the wind is blowing.

Sailing across the wind, with the wind abeam, is called "reaching." Sailboats can usually move faster when sailing across the wind that in any other direction. Some light sailboats with flat bottoms can move fast enough in a good breeze to lift out of the water.

"Trimming" means adjusting the sails to obtain the full advantage of the available wind.

"Tacking" involves turning the boat so that the wind comes at it from the opposite side. When sailing into the wind, this is called "coming about." On coming about, the bow is turned so that the wind crosses it.

Coming about in a sailboat is a comparatively safe maneuver. When the stern, or back of the boat is to the wind, a turn that brings the wind to the other side of the boat is called "jibing." Then, the wind crosses the stern quickly and the sail slams across the boat. This quick shift of forces can capsize a boat if the maneuver is not handled carefully.

Experienced sailors know where to place their weight in small sailboats and how to relieve dangerous pressure on the sails if a boat tips too far. This is done by slacking off or letting the sails out, so that some of the wind spills from them.

If a boat does capsize, the crew should hang onto it until rescued. Sailors, especially those who aren't good swimmers, should wear life jackets.

The most common rigs include catboats, sloops, yawls, ketches and schooners. Most small sailboats are catboats and sloops. A catboat has one mast far forward in the bow, and only one sail. A sloop has one mast toward the middle of the boat and two sails.

 

PARENTS' GUIDE

IDEAL REFERENCE E-BOOK FOR YOUR E-READER OR IPAD! $1.99 “A Parents’ Guide for Children’s Questions” is now available at www.Xlibris.com/Bookstore or www. Amazon.com The Guide contains over a thousand questions and answers normally asked by children between the ages of 9 and 15 years old. DOWNLOAD NOW!