NAVIGATIONG WITH GPS, LORAN, AND RADAR
ON THE MAINE COAST

DESPITE the new and wonderful instruments that have become widely available, the most important navigational tools for the coast of Maine remain those basic skills of piloting and dead reckoning. You will become alert to the color of rockweed under water (indicating a submerged rock) and grateful that swells break on submerged ledges. Most of the piloting along the coast in clear weather is done by eye and instinct and chart. Fog, of course, requires more formal.

GPS. As in most locations, GPS has become the standard electronic navigation tool in Maine. Differential transmitters are located in Portsmouth, New Hampshire and Brunswick, Maine.

Cruising sailors should be thoroughly comfortable with the use and limitations of GPS before they rely on it in the fog. The Coast Guard cautions against the common practice of relative navigation—using a previously observed position as a waypoint without first transferring it to a chart to check its accuracy—particularly for GPS. Likewise, waypoints obtained from sources other than charts should be plotted before being used. This guide lists harbor positions only for locating harbors, not for use as navigational waypoints.

Loran. Although the Loran system has taken a back seat to GPS, some fishermen still favor it for its accuracy in repeatability—its ability to return to a marked position.

Maine is covered by the U.S. Northeast Chain GRI 9960. As you approach Canada, the Canadian East Coast Chain GRI 5930 becomes stronger than GRI 9960. Loran signals may be distorted or blanked out by the enormous naval radio communications towers on Cutler Peninsula way Down East.

Radar. If the incentive to develop radar hadn’t been war, it probably would have been the Maine coast. Even when you can’t see your own bow, the bold shores show on the screen as sharp images, and you can identify navigational aids and monitor the movements of nearby vessels. Most lobsterboats and commercial fishermen have radar, as do many yachts. In heavy fog it is a blessing (see preceding section on fog, page 17), but not essential. One thing no yacht should be without, however, is a good radar reflector, mounted high.