More than just a book about sailing, Go for the Green is a clarion call to bring sailing out of the doldrums and into an expanded role as a catalyst for the more environmentally sensitive enjoyment of the sea. As a former Coast Guard Officer, active racer, cruiser and yacht designer, author Garry Hoyt combines a lifetime of sailing experience, with a weather eye to uncover the new challenges of global warming and the need for energy independence. His prediction that carbon based fuels will eventually draw the same degree of social scorn that smoking now receives, creates an automatic need for ingenuity in the harnessing of sail and solar power as better alternatives for water based recreation. To encourage readers along that path, Hoyt presents a philosophy and a variety of new design solutions to stimulate more creative design development. He makes his case in a simple, readable style that will interest all those who love the sea.
GO FOR THE GREEN
By Garry HoytiUniverse, Inc.
Copyright © 2009 Garry Hoyt
All right reserved.ISBN: 978-1-4401-4809-5Contents
Part I New Considerations........................................................................xiIntroduction.....................................................................................xiiiChapter 1-The Evolving Fortunes of Sail Power....................................................1Chapter 2-Single Handed Sailing Skill............................................................16Chapter 3-Wanted-A Small Boat That Adults Can Quickly And Safely Single Hand.....................20Chapter 4-The Sail Resort........................................................................25Chapter 5-The New Nature of "Day Sailing"........................................................29Chapter 6-Bring Back the Reach...................................................................32Chapter 7-A Better Way for Olympic Sailing.......................................................34Chapter 8-The Computer Assisted Atrophy of the Mind's Eye (CAAME)................................37Chapter 9-The High Cost of Low Price Petroleum...................................................40Chapter 10-What Need For Speed?..................................................................42Chapter 11-The Cascading Connectivity of Things..................................................45Part II Design Solutions.........................................................................49Introduction.....................................................................................51Chapter 1-Back To The Future-The Square Rig Returns..............................................53Chapter 2-The Hoyt Off set Rig (HOR).............................................................60Chapter 3-The Nantucket Bay Skimmer..............................................................71Chapter 4-The Quadrilateral Staysail Rig.........................................................75Chaper 5-The Caravel.............................................................................79Chapter 6-Multihull Applications of HOR..........................................................82Chapter 7-The Hoyt Jib Boom (HJB)................................................................86Chapter 8-The Balanced Hoyt Jib Boom (BHJB)-(Patent Pending).....................................93Chapter 9-Solar Electric Power As The Natural Ally Of Wind Power.................................100Chapter10-The Solar Cell Sail As New Dual Purpose Power..........................................105Chapter 11-Reprise...............................................................................108ABOUT THE AUTHOR.................................................................................112
Chapter One
The Evolving Fortunes of Sail Power
This is not a detailed history, but rather a conceptual review of where Sail has been with an eye to where it needs to go in the future. Technical points will be made in non-technical terms.
For perspective, it is important to recognize that for roughly three thousand years, sailing represented the preeminent technology of its day. Because sailing was the exclusive means of distance travel, trade, exploration, and military power. There is probably no other technology that matches sailing's sustained impact on the course of history and the spread of civilization. Sail ranks right up there with the wheel as a vital link in human progress because sail was literally the prime medium of discovery that opened up the modern world.
This then is a legacy of serious importance, and it is instructive to follow how sail technology has progressed and also how it has been slowed and distracted. Persistent market decline, particularly in the U.S., needs to be addressed. Here it is necessary to note that sailing technology cannot realistically be separated from sailing commerce because the two are highly interdependent. And so when markets fail or falter, it is often because technology has not fully kept pace with new circumstances and new competitive alternatives.
When we talk of sailing it is also important to separate sail from other more frivolous recreational diversions such as golf, or tennis, or bowling or basketball or baseball. All of these are artificial activities devised purely for amusement or exercise, they have no practical roots, nor do they aspire to any. Sailing, in contrast, is a very natural endeavor that sprang directly from practical need. From the earliest days man needed to get across large bodies of water as rapidly and reliably as possible for the business of fishing, of commerce, or warfare or exploration or carrying people and news.
Speculating about origins, one can reasonably suppose that wood's inherent power of flotation and the ability of flotation to lessen the carrying load, was easily and early observed. Lacking was something to add propulsion and mobility to flotation. Sail emerged as the best, indeed the only means to accomplish this, because it combined an abundant, free source of power, the wind, with an ability to function with a variety of the crudest shapes made with the simplest materials.
Thus the early cave man, seated astride a floating log, discovered that by spreading an animal skin, he could be blown in the direction of the wind, with more speed and less effort than by paddling. We can also imagine that these early cave man sailors rather quickly tired of the frequent tip overs that were the inevitable price of spreading sail atop a rolly log. A log is the prime example of a hull form with no form stability. Form stability is the stability that is derived from the shape of the hull, as opposed to stability derived from the weight of ballast. Resolving this issue of stability was an early on sail problem, and remains so today.
By way of solution, these early sailors figured out that lashing together two or three logs made a crude but stable raft that could carry more people, or a slain deer or whatever. Of course carrying more weight sank the log raft lower in the water, which increased the drag of wetted surface, which made the raft slower and quickly established the need for more sail power. And so they had to spread more animal skins to the wind via supporting sticks. And since holding up sticks with skins was hard hand work, they figured out how to tie vines to the sticks to hold them in place, and so rigging was born.
Of course crude log rafts with crude skin sails could really only go dead downwind, which was not necessarily where you wanted or needed to go. So somebody got smart, stuck a paddle vertically between the logs and discovered that by creating lateral resistance, the raft could be made to sail at right angles to the wind with reduced slipping sideways. That opened up another 180 of the compass. Not perfect, but markedly better than the hard work of constant paddling.
The critical, remaining problem was how to go against the wind, a move that defies logic. When you can take a strong natural force that's blowing against you and convert it to a drive force pushing you forward the other way, that's pretty neat, sort of like defying gravity. That's was sailing does quietly, naturally, with no cost and no pollution, a considerable feat that sets sailing apart from any other form of propulsion.
It can be seen that right from the very start that all the basic problems of sailing had to be faced and to some degree solved. These problems still exist for the most sophisticated designs of today, and they can be summarized as follows:
1. Provide sufficient sail power to create the drive force forward.
2. Provide sufficient stability (righting moment) to carry the sail power without tipping over.
3. Provide enough lateral resistance to keep from sliding sideways.
4. Minimize the burden of weight.
5. Minimize the drag of wetted surface.
You have only to comprehend these factors and you will have a grasp of the basic issues facing sailboat designers. Solve these problems better and you will have a better design. Understand them better and you will be a better sailor. And these solutions are not limited to trained engineers. Some of the best ideas in sailing have come from people with no previous training in sailboat design. There can even be some advantage to technical inexperience in that when you have no command of the complexities, you are forced into simplicities. Extensive technical knowledge can tempt the designer into arcane solutions that the sea has no tolerance for. As will be repeated in this book, simplicity is the ultimate sophistication.
Beyond its direct transportation utility, sail power, again right from the start, was a stern instructor in the consequentiality of things. Long before such concepts were fashionable, sail power at sea was an equal opportunity destroyer. It didn't matter whether you were white or black, male or female, old or young, noble or peasant, a mistake at sea meant down you went. The ocean is relentlessly even handed in its dispersed distribution of danger and sailors were repeatedly taught that there is nothing that man makes that the sea in its marshaled fury cannot break. As a result, sailors were obliged to acquire a cautious and disciplined behavior for survival. Yet they had to be willing to daringly cross those lines of restraint when opportunity beckoned. Thus, the lessons of risk and reward were early taught in sailing ships at sea because every voyage involved certain risk for uncertain results. Early sea captains were pioneer venture capitalists, but in contrast to the modern variety, there was no government bail out handy and their lives were often part of the high price of failure. And predatory pirates like Madoff didn't make bail or jail, they made the yard arms.
So it was that for centuries, prowess in sail power virtually dictated a nation's rate of success in commerce, warfare and the critical ability to find and control new lands. And naturally, the best minds of those times concentrated their ingenuity on designing and building sailing ships that could carry more men, more goods, more guns, with the ability to sail ever closer to the wind. For centuries, information and ideas literally moved at the speed of sail. This preeminence of sail assured a constant press for innovation, and progress was steady and occasionally dramatic.
Not every nation did this equally well, and their relative success or failure in sail power was directly reflected in their commercial, military and national power. Britain did it best for longest and by virtue of the naval superiority that derived directly from better sail power, that small island nation became the largest empire in the world. Being able to design, build and man superior sailing ships gave the British a naval edge that was the equivalent of a nuclear power edge in today's world. Because control of the sea ways meant control of the communications and supplies upon which military success was totally dependent. That the American colonies were able to succeed against this overwhelming power makes the story of the American Revolution all the more remarkable.
And for the emerging, independent American colonies, prowess in sail power was an early marker of the nation's potential. America led the world in the then important whaling industry and the American Clipper Ships represented the zenith of ship building skill-very daring and leading edge in its day. And progress in sail power was continuous as long as sail had dominant, commercial and military value.
But with the advent of steam power, sail abruptly lost its exclusive commercial and military value, and technological attention quickly turned elsewhere. Sailing drifted into the backwaters and eddies of a rich man's sport, and precipitously descended from primary transportation for everybody to recreational diversion for a few. What little design urgency remained was focused on racing, and racing quickly developed rules, mostly in the form of exclusions and complications often designed primarily to keep the game intact and comprehensible only to those already playing it. A sense of "newcomers need not apply" seemed to prevail. Sailing speed became important only in the relative sense-that is speed relative to other boats limited by the same rules. Rules are directly detrimental to innovation, and so sailing, which had previously invited and rewarded innovation, began to resist it and even outlaw it. These tendencies were a sure fire formula for shrinkage and stagnation.
A good illustration of this came when Nathaniel Herreshoff, the preeminent American designer produced the catamaran Amaryllis back in 1876 and soundly thrashed all the best monohulls in an important New York regatta. For this impertinence in daring to sail faster, Amaryllis and all multihulls were banished from the race course by the powers that were, an exile from which multihulls only recently began to recover. That's over one hundred years in the doghouse for the high crime of higher speed. It's hard to see how banning better speed in any way serves the cause of sailing. Yet much of the effort and structure of sailing organizations seems contrived to resist or inhibit speed improvements.
For example, One Design racing is a bedrock of sailing activity, and it remains both an enjoyable practice and the best way to develop good sailors. But the popularity of One Design racing is a contradiction of design progress because it specifically freezes boat design. That's a great way to ensure even racing but also a sure way to block technological progress. The One Design concept basically prohibits design innovation so it has to be viewed as a mixed blessing in terms of moving sailing ahead.
Sail's shift from commercial utility to racing frivolity has led to some awkward and unimaginative transitions.. When sail power's prime purpose was to carry cargo, cargo was used as ballast to solve the stability problem. That was very sensible, using what you had to carry for profit as the balance force to keep the ship upright. When the commercial focus was removed, sailing ships simply replaced operative cargo with inoperative lead. That worked, but what an uninspired solution. Weight is the first enemy of speed, which makes it illogical to begin any serious quest for improved speed with the automatic assumption of fixed lead for ballast. Limiting design vision to that tunnel is an unnecessary restraint that has confined sailing speed and popularity.
But enough of this historical debris, let's get on with some new thoughts and analysis.
The persistent problem that has forever challenged sailors is how to operate successfully in two interactive, often turbulent fluid mediums. The upper fluid, the air, is the drive force. The lower fluid, the water, is some six hundred times denser and serves as a flotation force and a drag force. The water holds you up by flotation, but holds you back by drag. The interface between these two fluids, the surface, is particularly complex because it is constantly agitated by surface waves, waves caused by both the wind and by the boat's own forward motion. Surface waves are a prime contributor to the speed inhibitions facing a sailboat.
How to extract forward progress from this interactive confusion is complex, because often the full force of wind and wave is directly opposed to the direction you want to go. In this case, the source of propulsion is perversely inclined to beat you back. The harder the wind blows the greater this counter force and the more agitated the supporting surface becomes. In many ways it is simpler to design an airplane or a submarine because each of those has an independent, controllable drive source, the engine, and each operates in just one fluid medium, air or water. Operating in just one medium gives you consistent characteristics. Operating in the zone where two fluid mediums interface, the surface, gives a sometimes baffling mix.
One of the first hydrodynamic rules that complicated boat design is the concept of "hull speed." Hull speed, which is numerically expressed by the formula 1.34 x the square root of the waterline describes the immutable limitation that governs the upper speed of displacement (non planing) hulls. By this rule, longer displacement hulls are always potentially faster than shorter displacement hulls. The reasons why behind this mandate are complex, but have mainly to do with the bow and stern waves that are automatically generated by any hull moving through the water. In a simplified explanation, longer hulls "stretch out" those speed stealing waves more than short hulls. No amount of extra engine power can alter these displacement hull speed limitations because the build up of bow and stern waves creates impenetrable water walls and the more power you add the more the hull just sinks into the hole between those walls created by bow waves and stern waves.
The key operative fact of this rule is that fair and slender hulls will reach "hull speed" more quickly and with less power applied than shorter or less fair hulls. Obviously there are strong, practical considerations that limit how narrow a hull can be and still retain some semblance of stability.
Planing hulls escape this hull speed formula limitation by rising up and riding over the bow wave, which quickly reduces the hull's wetted surface drag, a release resulting in higher speed and flatter wake. But obtaining this advantage requires lighter hull weight, significantly higher propulsion power and broad, flatter after hull shapes, which are much less efficient in rough seas or lower speeds. So those conditions disqualify planing hulls from practical cargo carrying use.
Multihulls can also escape the "hull speed" formulaic limitation by gaining stability through the conjoined use of two or three slender hulls whose slenderness would be prohibitively unstable in single hull configuration. But this multihull speed advantage requires wide beam, light weight and connecting bridge height sufficient to be free of wave slamming. Nonetheless, by their narrowness multihulls can avoid the "hull speed" trap and this allows them to be inherently faster then displacement hulls of similar length.
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Excerpted from GO FOR THE GREENby Garry Hoyt Copyright © 2009 by Garry Hoyt. Excerpted by permission.
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