Close Quarters Maneuvering for Small Craft
a book by Charles T. Low
by Charles T. Low, author of Boat Docking
Wind contributes more to the challenge of docking than all of many other factors combined. Although there are indeed other individual circumstances in which docking may be exceedingly difficult, wind tops the list not only because it can be so hard to deal with, but because it is so common a confounding variable. Wind features prominently in boaters casual banter about docking, and we all often observe it as the source of trouble for a variety of boats in and around the docks.
Wind make things happen quickly! Compare this to those rare, completely calm days, when a docking can be halted at any stage, giving lots of time to re-organize our thoughts and our lines (in that order!), or to move to a different spot on the boat in preparation for fending off or for stepping ashore. Not so when a wind blows! Even a light breeze of 5 or 10 knots, common enough that we wouldnt want it to deter us from boating, imparts a sense of urgency and immediacy to what would otherwise be a much more relaxed docking.
Different boats and types of boats vary tremendously in the intensity of their responses to wind, but the general principles apply to all of them. Each boater deduces individually just how much the various wind effects apply to his or her boat, largely by experimentation, on the water. (Hint: practise. Try things! If unsure of the way a boat will respond, make your initial observations in other than close quarters.)
Blown Around The most obvious wind effect is that it blows a boat along. What is less apparent is how fast it can move a vessel. Beginning boaters often recognize the quality of the winds effects more than the quantity! Wind often doesnt give you a lot of time to sit and ponder your situation!
Even less widely appreciated is the very strong yawing (turning) effect of the wind on a boat hull. This applies to supertankers as well as to canoes, and to all boats in between (unless they have sails up, in which case the yawing effect is different in nature but thats a separate discussion).
The result is that the boat is blown broadside to the wind. If this seems counter-intuitive to you, it may be some slight consolation to know that it does to me too, but regardless, thats the way it is. Physicists have drawn wind pressure diagrams (in their spare time) which show why hulls react this way, and by golly, theyre right. You can try it: take the boat out of gear, center the helm, and then wait some hulls will turn beam to wind very quickly, others slowly, but there are very few, if any, exceptions to the rule that they do go beam to wind.
Exceptions? Well, a vessel with high windage at one end or the other may weathervane, to some extent. Planing hull power boaters take note: your bow is high and light, and your stern deep and heavy. (Were talking about your boat, still; dont let this affect your body image.) Nonetheless, youll be amazed at how weakly most boats weathervane, and at how strongly they go broadside to the wind.
A related caveat about the yawing effect of wind is that it varies enormously, in some boats, depending on which direction the boat starts from. Put the higher windage end of the boat towards the wind, and the vessel will turn quickly, and vice versa. So, to take our planing hull power boat again, if taken out of gear while in a headwind, it will blow broadside to breeze quickly; but if it starts out stern to wind, it may be some time before it gets around to turning. The implications of this will arise shortly.
Going broadside to the wind means going broadside to the waves, too, in most cases not a big consideration in close quarters, but worth noting should you ever suffer engine failure on the open water.
Maneuvering In Wind We will examine handling a vessel in various combinations of i) making headway vs. making sternway, and ii) in winds coming from ahead, astern, and abeam.
Conclusion There is no conclusion to Boat Docking the potential for more progress never ceases. Thank goodness that this is the case; how unexciting life and boating would be otherwise!
As surely as the wind blows, understanding its effects on boats is half the battle. (Add up all of the halves that constitute this struggle, and you have quite a large whole the various factors must intersect and overlap!) One of the many other halves, Momentum, was discussed here recently, and between it and wind rests perhaps two-thirds (the math is getting less convincing) of the understanding required for close quarters maneuvering for small craft.
Let this information soak in and become a part of you, by practical experimentation on the water, and expect it to continue gradually to ingrain, more and more deeply, for your whole boating career.
About the book Boat Docking (Close Quarters Maneuvering for Small Craft) is a recently published book about how to dock a boat! It contains many concrete examples of boat docking, from the elementary to the advanced, and also has chapters discussing the theory of close quarters maneuvering.
This is a softcover publication, 7"x9" (18x23 cm), 88 pages in length, with roughly 25,000 words and about 140 clear, simple illustrations. (That's a lot of illustrations!) It's a comfortable (winter) evening's read, or a ready on-board reference and discussion document.
The distillation that has resulted is not, to our knowledge, reproduced elsewhere. This book is tightly focused only on slow-speed handling of small craft, and as such it is very complete and thorough. It has an excellent balance of technical analysis and practical boat-docking recipes.
Charles T. Low, the author of Boat Docking, is a recreational boater in the Thousand Islands on the St. Lawrence River. He and his family spend much of their summer vacations, weekends, and many evenings, on the water. Charles likes the beauty and tranquility of the islands, and also enjoys boating an excellent match of process and product!
Visit the Boat Docking web site for further information.
|Boat Docking Wind is Copyright © 1997 ctLow|
Charles T. Low, Harvey Island Enterprises