Learning to trace the edge of the wind by keeping the canoe sailing on the edge of the no go zone is a key aspect of learning to sail up wind, but it is by no means the whole story. If you really want to learn to sail up wind efficiently, then you will need to gain an understanding of wind shifts.
Wind Shifts – Beginners
On long thin lakes such as those found in the Lake District, novice sailors sometimes get used to the idea that the wind blows down the lake. This is broadly true, but we should remember that the wind rarely blows directly down the lake, and that sailing on one tack may allow us to point much closer to the windward end of the lake than the other. The wind direction may vary quite considerably during a sail and will swing from the directly down the lake direction to either blowing from the left hand side or the right hand side. After a big wind shift I have seen a sailor happily sailing along, tracing the edge of the new wind direction, and quite unaware that they were now sailing back towards their starting point.
Wind Shifts – Intermediates
So, you’re sailing along in a straight line and the wind direction changes slightly, shifting around so that the wind is blowing from more in front of you (Fig. 11). If you continue sailing in a straight line, you will feel the boat slow and possibly even see the luff of the sail bubble as the wind from ahead of the boat starts to make the sail flap. Instinctively you adjust the heading of the boat to keep the tell tales flying. The boat continues sailing fast.
Meanwhile your friend, who is sailing behind you, has taken a different approach. Seeing that your boat is now pointing further away from the island you are sailing towards, she tacks. The change in wind direction lifts your friend’s boat because, as she is now on the opposite tack, the shift makes her boat point closer to the windward mark (Fig. 12).
Wind Shifts -Advanced
Good sailors are often able to spot a wind shift before it happens. You may have observed dark squalls making an oval pattern on the water as they move down a lake. If one of these squalls passes behind you, the resulting wind shift will allow you to point closer to your windward objective. Sailors call this being lifted. Alternatively, if the squall passes in front of you, you will either have to tack, or bear away and point further away from your objective. Sailors call this being headed.
Terrain can also be a factor which influences wind shifts. Headlands can bend the wind in a direction that is predictable. The wind tends to run parallel to the shore line, so sailing towards a headland which is upwind of you will often produce a lifting shift.
The key here is observation – and plenty of practice, so you develop an informed feel for how wind can behave and how you and your sailing canoe respond to it.