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So Which Way Is Up? (JohnB) (Adapted from a pamphlet by JohnB, which appeared at the winter meet.)
Sometimes, when I am watching our fleet plug its way to windward, I am struck by how far we have progressed over the years. There has been a continual slope of improvement, both in terms of gear and of us, the sailors. In the early days the technology and rules were largely based on previous ACA experience. We had little understanding of our own and we needed years to acquire it. We had fun learning. Within a very short time, however, the desire to point higher and go faster was in evidence. First Gunter and then Bermudan rigs began to appear with purpose-built hulls and asymmetric leeboards, culminating in DaveS's fully battened sail on the Selway Fisher 'Waterman' in 1995. At the time this was regarded as quite a brave move and we all watched with interest, but of course like most of Dave's ideas it worked beautifully. Most of us regard these developments with pleasure and interest. It manifests a certain vitality within the group; we are alive to new ideas and that can only bode well for the coming years.
It has also been suggested that, as a result of global warming, the weather patterns are changing, as we are either sailing in F1/2 or it's a F5/6 and there doesn't seem to be much in between. Whether there is statistical evidence to support this remains to be seen (we are currently in correspondence with the Met Office regarding the matter). If it were so, then perhaps we might have to revise our rules concerning sail area.
There is always a tendency to develop along more or less established lines, based on what has gone before ("Onwards and upwards", we cry), but if only we knew which way was up! We develop our rigs in accordance with the sail aerodynamics of bigger boats (where the research is done) and forget that our mastheads barely reach the level of their booms. Recent reading has led me to the conclusion that one of the fundamental problems we face is that our canoes are operating well below the clean air flow, where flow is turbulent in direction and speed. The angle of attack and velocity for our little rigs is constantly changing, even within the height of the sail. At this level the velocity can vary between zero at ground level and 25 knots at the head of the sail.
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