Diagram No. 8 depicts the manœuvre of tacking that is the method of "going into stays," or shifting from one tack to the other. Fig. 1 shows a boat steering "full and bye" on the starboard tack. It becomes necessary to go about. "Helm's a-lee!" cries the man at the tiller, at the same time easing the helm down to leeward and causing the boat's head to fly up in the wind. The jib sheet is let go at the cry "Helm's a-lee!" decreasing the pressure forward and making the boat, if well balanced, spin round. A modern racer turns on her heel so smartly that the men have all they can do to trim the head sheets down before she is full on the other tack. Some of the old style craft, however, hang in the wind, and it sometimes becomes necessary to pay her head off by trimming down on the port jib sheet and by shoving the main boom over on the starboard quarter (Fig. 3). Soon she fills on the port tack, and goes dancing merrily along, as shown in Fig. 4.
In beating to windward in a strong breeze and a heavy sea leeway must be considered.
Leeway may be defined as the angle between the line of the vessel's apparent course and the line she actually makes good through the water. In other and untechnical words, it is the drift that the ship makes sideways through the water because of the force of the wind and the heave of the sea, both factors causing the craft to slide bodily off to leeward.
This crab-like motion is due to a variety of causes, to the shape of the craft, to her trim, and to the amount of sail carried, and its quality and sit. Boats deficient in the element of lateral resistance, such as a shallow craft with the centerboard hoisted, will drift off to leeward at a surprising rate. A deep boat of good design and fair sail-carrying capacity will, on the other hand, if her canvas is well cut and skillfully trimmed, make little or no leeway. In fact, she may, under favorable circumstances, eat up into the wind and fetch as high as she points.
Diagram No. 7.
A Long Leg and a Short Leg.
Leeway is always a dead loss, and to counteract it is always the aim of the practical seaman and navigator. Captain Lecky, in his admirable work, "Wrinkles in Practical Navigation," puts the case clearly, and his advice should be followed whenever feasible. He says: "Suppose a vessel on a wind heading NW by N, under short canvas and looking up within three points of her port, which, accordingly, bears north; but, owing to its blowing hard, she is making 2-1/2 points leeway. Clearly this vessel is only making good a NW by W1/2W course, which is 5-1/2 points from the direction of port. Let her speed under these conditions be, say, four knots per hour. Now, if the yards are checked in a point or so, and the vessel be kept off NW by W, she will slip away much faster through the water, and probably will make not more than half a point leeway. This keeps the course made good exactly the same as before, with the advantage of increased speed. Therefore, if you can possibly avoid it, do not allow your vessel to sag to leeward by jamming her up in the wind. Keep your wake right astern, unless it be found from the bearing of the port that the course made good is actually taking the vessel away from it, in which case it is obvious that the less the speed the better."
This excellent counsel applies to every kind of sailing vessel, whether square-rigger or fore-and-after, whether used for business or pleasure. It is of no avail to pinch a boat for the purpose of keeping her bowsprit pointed for her destination, when it is obvious that she will only fetch a point several miles to leeward. Keep the sails clean full and the boat will make better weather of it, as well as greater speed. It may frequently be necessary to "luff and shake it out of her" when struck by a hard squall, or, by the aid of a "fisherman's luff," to clear an object without tacking, but a good rule is to keep a sailing craft moving through the water and not permit her to pitch and rear end on to the sea.
Diagram No. 8.
The Manœuvre of Tacking.