Perhaps you like to plan your passages when you’re away from your boat. Maybe you spend a lot of time sailing on other people’s boats. Maybe you just like to take your nav gear home at the end of the day, or you like having a backup in a bag. Whatever the reason, there’s a lot to be said for being able to tote along your own tried and proven gear.

My own experiences on any number of deliveries, races and boat tests have long since convinced me of the value of this approach. In many cases, for example, I’ll run my portable gear in parallel with a new boat’s built-in navigation system. It can take time to become familiar with an unfamiliar setup, and when stepping aboard a new boat it’s nice to have a familiar digital platform up and running from the get-go.

The first step is to install a feature-packed navigation software program—like those offered by Nobeltec, Rose Point, Maptech, Fugawi or the Capn—on your laptop. Just load it up, plug in a 0183 GPS cable or stick a standalone GPS unit in a PCMCA slot, and your laptop becomes a versatile digital charting display.

Over a decade ago, I loaded a copy of Nobeltec’s Visual Navigation Suite 4.0 onto a laptop and took it on a transatlantic run, using it mostly at either end of the passage. Since then I’ve run up and down the coast and made ocean passages with newer editions of Nobeltec software and Rose Point Coastal Explorer. I’ve found both systems solid and dependable. I’ve also found Maptech and Fugawi software to be user-friendly and cost-effective options.

The best way to tell if a program is right for you is to spend time at a boat show being walked through its features by one of the company’s software gurus. Then go home and download the free trial version that many companies offer. The fact that all of the raster and vector charts covering U.S. waters are available for free from NOAA (nauticalcharts.noaa.gov/staff/chartspubs.html) makes the entry into digital navigation both easy and affordable. Maptech’s Offshore Navigator Lite sells for $99.95 and comes with a DVD that includes a complete set of U.S. charts. A SiRF III GPS fits into a PCMCIA slot in a laptop and costs another $49.95. For a grand total of about $150 you can turn your laptop into a portable chartplotter.

WHAT’S IN THE BAG?

Much of the gear I haul from boat to boat in my portable nav kit requires no batteries. In fact, some of the most important equipment is the same stuff navigators have been counting on for decades. My goal is to have a versatile alternative at hand, just in case the vessel’s navigation suite is lacking—or if all the lights and electronic equipment go dark.

Let’s start with the basics. I prefer push-button mechanical pencils rather than the familiar old wooden standbys that always seem reluctant to keep a sharp point. My “analog delete key” is an art gum eraser, which I use regularly to rid charts of previous plots that can confuse current work. My preference, when it comes to dividers, is the gear-synchronized, one-hand-span locking Weems & Plath CP0176—a favorite among pro navigators. I also use conventional parallel rules and a #120 roller plotter, along with an isosceles right triangle to quickly scribe parallel and perpendicular lines.

Dig deeper into my nav-to-go bag and you’ll uncover a pair of Steiner 7×50 binoculars with a built-in hand-bearing compass, along with a simple hockey puck-type HB compass that I regularly put to good use. Shooting a quick round of bearings on identifiable shoreside targets is an easy way to double check what’s playing out on a digital plotter screen. The fix can be plotted on a paper chart for comparison, or you can move the DCS cursor on your laptop to the charted object ashore and compare your visual bearing to the electronic one. Be sure to either set the bearing function to read in magnetic rather than true degrees, or correct the hand bearing compass reading for variation.

Whenever I go offshore I carry either a chart book or a few carefully chosen individual paper charts that cover the route and have enough detail to make a safe landfall at either end of the voyage. I also bring along—or make sure the vessel has—hard copies of the sailing directions and a cruising guide detailing our destination. Additional publications can be kept in PDF format on the laptop’s hard drive. Tucked even deeper in my nav bag is an extra pair of glasses, a powerful magnifying glass and a couple of small flashlights and a headlamp—these work equally well whether plotting a fix after the lights have gone out or searching for a leak in an engine’s coolant system.

I also usually bring a waterproof handheld GPS and VHF radio. The radio lets me listen to local weather broadcasts and make Channel 13 bridge-to-bridge contact with passing ships while leaving the boat’s radio set on 16 or scanning multiple channels. The handheld GPS is a backup, but can come in handy when a long dinghy ride to town becomes a fogbound passage on the trip back to the boat.

There’s also a 1in x 6in cylindrical high-intensity Inova LED flashlight lurking near the bottom of the bag. It’s bright and narrow-beamed enough to be considered a mini-spotlight and can turn an unlit buoy into a brightly lit beacon. I was reluctant at first to carry it because it uses 123A lithium batteries rather than the AA alkalines that the VHF and GPS use, but its light weight and tightly focused beam won me over.

Finally, on ocean passages I lug along my David White Mark II Navy sextant and a nautical almanac, and install Star Pilot software on my laptop for reducing sights. Although a laptop only consumes 2 or 3 amps when running, that can add up to 48-72 AH per day—as much as an efficient refrigeration system. Before assuming that the house bank will be able to simply take the additional load in stride, you should make some capacity calculations. These energy demands may eventually drive me to invest in an iPad or other tablet, but I prefer the way digital charting software handles on a modern laptop, so for now I’ll settle for a bright digital display at the expense of cold beer.