CHAPTER 1

About This Book

In the fog-shrouded past of a generation ago, navigation was still done as ithad been for centuries. A navigator would set forth on the wide waters armedwith his (or her) charts, dividers, course plotter, compass, eyes, and wits.Along unfamiliar coasts or through bad weather, he "felt" his way from port toport. Any charted navigation buoy or landmark was a valued reference; withbearings and distances from these, he could fix a point on a chart and say withconfidence, "I am there!"

But such confidence would be tested if those charted objects ever slipped fromview. In darkness or thick fog, the navigator could calculate only hisapproximate position. This calculation, this dead reckoning,worked when done well, but it wasn't dead on. Without precise fixes, thenavigator could only strain his eyes and ears to hear the reassuring peal of abell buoy or (heaven forbid) to see the foaming white surge of breakers overlurking rocks in the mist ahead.

But all that has changed.

Just prior to the close of the last millennium, GPS (the Global PositioningSystem) was born. Within a few years, GPS receivers had become popular andaffordable. Nowadays, if you have a hundred bucks and two AA batteries, you canbuy a handheld GPS and use it to plot your location anywhere on the Earth'ssurface. Just one glance at the GPS screen will tell you your precise location,your speed, your heading, and the direction and distance to your nextdestination. It will even give you the time of day.

GPS has made navigation easy. Within hours you can learn enough to get out onthe water. But those AA batteries won't last forever, and neither will your GPSreceiver, 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 generationpast. You should know how to plot courses on a chart with dividers and parallelrules, steer them by compass, fix your position with visual bearings, and deadreckon when no bearings are possible. In short, you should know how to navigateby 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 ofstyle and never lose their usefulness. You'll learn how to use a GPS receiver aswell as a handful of other modern electronic navigation tools, and you'll learnwithin a context that will strengthen your overall understanding of navigationconcepts. Despite all the new technologies, nautical charts remain the singlemost essential tool of the navigator, and unlocking their language stillrequires practice. So, it's important that we learn about navigation's pastbefore we can fully understand its future. After all, a straight line mayrepresent 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 ofyour learning while you're boating, not before. Round up the recommendednavigation tools and spend a weekend with The Weekend Navigator, andyou'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 areference guide. The early chapters will quickly get you up to speed and out onthe water. The later chapters will provide you with the advanced techniques andtools 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 betweentraditional piloting and modern-day navigation. You'll learn the key concepts ofwaypoint navigation, and you'll be introduced to "The Three Steps ofNavigation." Chapter 4 introduces the necessary tools, both traditionaland digital.

Part II deals with prevoyage planning—the first of the three stepsin navigation. These chapters show you how to plot safe courses on both paperand digital charts and how to enter waypoints into a GPS.

By Part III, we've plotted courses and are ready to follow them acrossthe water. Navigating underway is the second step in navigation, and thesechapters teach you how to use a GPS, a computer, and a chartplotter from thehelm.

The third and final step in navigation is to confirm your electronics throughindependent means. Double-checking is the focus of Part IV. Thesechapters 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 mostcareful navigation. Part V discusses how to prepare for changingconditions.

Part VI is a virtual wish list of high-tech navigation equipment; eachchapter demonstrates how to use a particular tool and explains what it doesbest. Armed with this information, you can decide which tools are right for yourboat.

Each of the chapters in Part VII explores an advanced topic innavigation. These tips and techniques are easily referenced and ready to helpyou develop into a seasoned navigator.

The principles of navigation were established long ago. A GPS receiver fixesyour position by crossing circles of equal distance, just as celestialnavigators have been doing for centuries and coastal pilots have been doing formillennia. But the electronics revolution is bringing us rapidly evolving toolsthat allow us to navigate more precisely and with increasing ease and safety. Asone example, the downloadable software described in Appendix 1 is updated atleast yearly. I invite you to visit www.weekendnavigator.net, where Ikeep track of updates, tips, and late-breaking information on navigationsoftware and navigation in general.

No other pursuit can set you free the way boating can. The infinite expanse ofblue water and sky invites you to leave your everyday stresses behind. Even ashort weekend outing on local waters can make you feel as though you're worldsaway from home and work. But no matter how far you drift, the skills andtechniques you'll learn from The Weekend Navigator will ensure that youcan always return. (Whenever you're ready, of course.) And regardless ofconditions—be it the foggiest day or the darkest night—you willalways 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. Inyour travels by car, you follow roads. Although it is possible to select thewrong road or route to your destination, you will rarely encounter terrainhazards 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 thegreat freedom and the challenge of navigating a boat, because unseen hazards maylurk below the surface of what looks like safe water. Consequently, a major partof marine navigation is avoiding hazards while traveling from point A to pointB.

In planning for travel on land, you pull out maps and select the appropriatesequence of roads to reach your destination. The roads generally are clearlydefined and marked, so they are easily identified while you are underway.Planning for travel on the water is an entirely different matter. You will needto make up your own roads. Once on the water, you may encounter few markings orsigns to guide you along your chosen path.

The Three Steps of Navigation

To clarify the process of marine navigation, it is helpful to consider it inthree sequential steps, the distinctions among which may blur in practice.

Prevoyage planning—deciding which path to take

Navigating underway—following the selected path

Double-checking—confirming by independent means that you haveselected the right preplanned path and are where you think you are

A skilled navigator will not rely only on electronic devices for the latterdetermination. He will use his ship's compass, his eyes, his charts, and othertools to reassure himself that those marvelous but inscrutable electronic blackboxes are still displaying reliable data. But more on this momentarily.

Step 1—Prevoyage Planning

Planning before you set out is ideal, but it's a safe bet that you will findyourself planning on the fly as conditions or destinations change. Nonetheless,you need to plan. And to plan, you need charts and the know-how to use them.

How much planning is enough? It depends on the kind of boating you will be doingand the waters and conditions in which you will be doing it. For example, youshould consider whether you will be:

* voyaging directly from one location to another

* tacking into the wind or waves

* or meandering freely around a region while fishing or just enjoying your timeon the water

How you plan and how you navigate safely are a little different for each.

Prevoyage Planning It makes a great deal of sense to preplan for thewaters you intend to frequent. You can plan a sequence of point-to-point legsthat get you to your destination, or you can isolate areas you want to avoid ona meandering excursion or fishing trip. Then annotate your charts and enter thecorresponding information into your electronics. (These are good tasks forevenings or the off-season.) With appropriate preplanning, you will be wellprepared for most of the navigating tasks you may face.

You can take a cue from what a number of commercial chart companies provide. Forexample, Maptech paper chart kits come with course segments preplotted betweenprominent navigation aids. The distances between these nav aids and the coursesto steer from one to the next are already labeled. You can navigate from pointto point or buoy to buoy along these segments and be reasonably confident thatyou will not encounter underwater hazards. The coordinates of the endpoints areoften printed on the chart so you can enter them into your GPS, as illustratedin Figure 2-6 and explained in Chapter 5. This is a handy tool.

These preplotted segments don't cover all the paths you may wish to take,however, nor do they extend into harbors or coves you might want to visit alongthe way. As you venture away from preprinted course lines—or if you'reusing government charts, which don't include preplotted courses—you willneed to plot your own courses. You can customize any paper or electronic chartby preplotting course segments. Then you can measure the coordinates of theplotted waypoints and enter them into your GPS.

On the other hand, while you're fishing or just enjoying a day on the water, youmay wish to move around more or less at random rather than follow prescribedpaths. In this case, you will be more interested in marking where you donot want to go. Navigation then becomes a process of avoiding thehazards you have highlighted on your charts and stored in your electronics.

Preplanning techniques are described in Chapters 5, 6, and 7.

Planning on the Fly We're all susceptible to impulses, and the impulseto change course is a strong one. But when you do, you must choose a safe path.It's a good idea to keep up-to-date charts near the helm while you're underway.You'll need to plot your present position on the chart and examine your intendedpath for any potential hazards before you follow a new course. If you usedigital charts, you can do the planning in real time on your screen. Planning onthe fly is described in more detail in Chapter 13.

Step 2—Navigating Underway

You made your plan; the next step is to follow it. You'll steer clear of anycharted obstacles or shallow areas by navigating from waypoint to waypoint alongpreplotted paths, monitoring your navigation equipment to make sure you stay oncourse. Sure, navigation requires attentiveness, but it's far easier thancontinually trying to figure out where you are and where you are going.

Monitoring your progress along your intended path helps you determine whenyou're approaching the next waypoint or destination and thus when to execute aturn or look for navigation aids.

On the water, under real-life conditions, it is quite easy to stray from yourintended course. How will you know? Your GPS can provide that information (seeChapters 8 and 9). It's also the subject of the third step ofnavigation—double-checking. If you do get off course, you'll need toregroup and replan. GPS will help get you back on course. Chapters 8 and9 also describe some relatively simple tips for staying on course in thefirst place.

Step 3—Double-Checking

GPS and other electronic navigation tools are highly reliable, but they're notfoolproof. They can fail or occasionally provide faulty or incompleteinformation. You might misread your instruments or the chart, or you might enterthe wrong waypoint into your GPS receiver. Mistakes happen.

As navigator, one of your chief roles is to confirm that you are where you thinkyou are. Your boat and your crew are counting on it.

There are simple techniques for double-checking your navigation. Most boatersrely on a GPS receiver as their primary position sensor, but experiencednavigators confirm their positions using their "seaman's eye." Simply put, youshould compare GPS readings against your surroundings—what hikers callgroundtruthing. This way you can be sure that your electronics are working andremain aware of any uncharted hazards. You can also use radar or otherelectronics to check your position independent of GPS. The idea is not to relysolely on any one device. Always cross-check with other sources. Chapters10 and 11 provide techniques for doing this.

Piloting without Electronics

Traditional piloting is navigation with the aid of landmarks, land features, andcharted navigation aids; you use these visual clues to continually update yourposition while underway. Charted features are also used in the planning process.Whenever possible, your chosen paths will begin and end at navigation aids, soyou'll be able to visually verify your navigation. More generally, takingbearings from your boat to any charted objects in your field of view is thetime-honored way of figuring out where you are at any given time. This is thefoundation of traditional piloting. GPS does exactly the same thingelectronically.

Navigation Aids

As you will learn in Chapter 4, buoys, lights, and other navigation aidsmark prominent hazards, channels, and harbors and provide boaters withinformation of many kinds. Unfortunately, these aids may not be placed insufficient quantity to mark every hazard or every change of course you mightwish to take, particularly in areas away from main channels. Some navigationaids located within harbors are locally managed and may not appear on yourcharts, or they might even have been moved from their charted locations. Chartsshowing fine-grained harbor detail are usually prepared only for harbors thatreceive commercial traffic, so you may need to rely upon the knowledge of localmariners—"local knowledge," it's called—or you may be on your own tomark these locations.

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