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The WEEKEND NAVIGATOR
Simple Boat Navigation with GPS and Electronics
By Robert J. Sweet
The McGraw-Hill Companies, Inc.Copyright © 2012Robert J. Sweet
All rights reserved.
About This Book
In the fog-shrouded past of a generation ago, navigation was still done as it had been for centuries. A navigator would set forth on the wide waters armed with his (or her) charts, dividers, course plotter, compass, eyes, and wits. Along unfamiliar coasts or through bad weather, he "felt" his way from port to port. Any charted navigation buoy or landmark was a valued reference; with bearings and distances from these, he could fix a point on a chart and say with confidence, "I am there!"
But such confidence would be tested if those charted objects ever slipped from view. In darkness or thick fog, the navigator could calculate only his approximate position. This calculation, this dead reckoning, worked when done well, but it wasn't dead on. Without precise fixes, the navigator could only strain his eyes and ears to hear the reassuring peal of a bell buoy or (heaven forbid) to see the foaming white surge of breakers over lurking rocks in the mist ahead.
But all that has changed.
Just prior to the close of the last millennium, GPS (the Global Positioning System) was born. Within a few years, GPS receivers had become popular and affordable. Nowadays, if you have a hundred bucks and two AA batteries, you can buy a handheld GPS and use it to plot your location anywhere on the Earth's surface. Just one glance at the GPS screen will tell you your precise location, your speed, your heading, and the direction and distance to your next destination. It will even give you the time of day.
GPS has made navigation easy. Within hours you can learn enough to get out on the water. But those AA batteries won't last forever, and neither will your GPS receiver, for that matter. Sure, the quantum leap in technology is impressive, but no one has yet invented electronics that won't eventually break down. Therefore, it's important that you also learn the techniques from a generation past. You should know how to plot courses on a chart with dividers and parallel rules, steer them by compass, fix your position with visual bearings, and dead reckon when no bearings are possible. In short, you should know how to navigate by your wits.
The Weekend Navigator will teach you how to navigate in the digital age, but it will also teach you the time-honored techniques that never go out of style and never lose their usefulness. You'll learn how to use a GPS receiver as well as a handful of other modern electronic navigation tools, and you'll learn within a context that will strengthen your overall understanding of navigation concepts. Despite all the new technologies, nautical charts remain the single most essential tool of the navigator, and unlocking their language still requires practice. So, it's important that we learn about navigation's past before we can fully understand its future. After all, a straight line may represent the shortest path between two points, but it isn't always the safest.
But here's the good news: with GPS on your side, you can safely do a lot more of your learning while you're boating, not before. Round up the recommended navigation tools and spend a weekend with The Weekend Navigator, and you'll be ready to start putting your navigation skills into practice. That's the GPS revolution.
Navigating This Book
This book can be considered both a "quick start" guide to navigation and a reference guide. The early chapters will quickly get you up to speed and out on the water. The later chapters will provide you with the advanced techniques and tools that only old salts know.
Part I gives you an overview. Using a sample cruise as an example, Chapters 2 and 3 help you see the important differences between traditional piloting and modern-day navigation. You'll learn the key concepts of waypoint navigation, and you'll be introduced to "The Three Steps of Navigation." Chapter 4 introduces the necessary tools, both traditional and digital.
Part II deals with prevoyage planning—the first of the three steps in navigation. These chapters show you how to plot safe courses on both paper and digital charts and how to enter waypoints into a GPS.
By Part III, we've plotted courses and are ready to follow them across the water. Navigating underway is the second step in navigation, and these chapters teach you how to use a GPS, a computer, and a chartplotter from the helm.
The third and final step in navigation is to confirm your electronics through independent means. Double-checking is the focus of Part IV. These chapters reveal some low-tech tips that will keep you on the right track.
Electronic failures and forces of nature can play havoc with even the most careful navigation. Part V discusses how to prepare for changing conditions.
Part VI is a virtual wish list of high-tech navigation equipment; each chapter demonstrates how to use a particular tool and explains what it does best. Armed with this information, you can decide which tools are right for your boat.
Each of the chapters in Part VII explores an advanced topic in navigation. These tips and techniques are easily referenced and ready to help you develop into a seasoned navigator.
The principles of navigation were established long ago. A GPS receiver fixes your position by crossing circles of equal distance, just as celestial navigators have been doing for centuries and coastal pilots have been doing for millennia. But the electronics revolution is bringing us rapidly evolving tools that allow us to navigate more precisely and with increasing ease and safety. As one example, the downloadable software described in Appendix 1 is updated at least yearly. I invite you to visit www.weekendnavigator.net, where I keep track of updates, tips, and late-breaking information on navigation software and navigation in general.
No other pursuit can set you free the way boating can. The infinite expanse of blue water and sky invites you to leave your everyday stresses behind. Even a short weekend outing on local waters can make you feel as though you're worlds away from home and work. But no matter how far you drift, the skills and techniques you'll learn from The Weekend Navigator will ensure that you can always return. (Whenever you're ready, of course.) And regardless of conditions—be it the foggiest day or the darkest night—you will always be able to pull out a chart and confidently state, "I am there!"CHAPTER 2
What Is Navigation?
Navigating on the water is vastly different from piloting your automobile. In your travels by car, you follow roads. Although it is possible to select the wrong road or route to your destination, you will rarely encounter terrain hazards as long as you stay on the roadway. But there are no roads on the water, and your choices for travel appear virtually limitless. This is at once the great freedom and the challenge of navigating a boat, because unseen hazards may lurk below the surface of what looks like safe water. Consequently, a major part of marine navigation is avoiding hazards while traveling from point A to point B.
In planning for travel on land, you pull out maps and select the appropriate sequence of roads to reach your destination. The roads generally are clearly defined and marked, so they are easily identified while you are underway. Planning for travel on the water is an entirely different matter. You will need to make up your own roads. Once on the water, you may encounter few markings or signs to guide you along your chosen path.
The Three Steps
Excerpted from The WEEKEND NAVIGATOR by Robert J. Sweet. Copyright © 2012 by Robert J. Sweet. Excerpted by permission of The McGraw-Hill Companies, Inc..
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