PassageMaker - August 2010

WATERLINES

On a cruise in Maine some years ago, we had just entered the mouth of Somes Sound, that gorgeous glacial cut that nearly bisects Mount Desert Island, when the image of the chart on the multifunction display suddenly went dim. Up close, we could make out faint ghosts of the shoreline on either side of the sound, but that was all. The screen showed no details of rocks to be avoided, navaids to be honored, or depths in places where we might need to drop an anchor.

At times like these, your first inclination is to look around, take some general bearings, and get a fix on where you are. As I peered ahead, the sun shone brightly, a steady breeze blew across the cold, blue waters, and the visibility was excellent. But behind us, as if timed perfectly to coincide with our electronic dilemma, the moorings and features of Southwest Harbor melted away as a lead-gray fog bank rolled in.

This was not good news for our intrepid crew, who had planned to use the single chart plotter aboard for primary navigation, guiding our way south and west behind the offshore islands that protect Isle au Haut Bay and Penobscot Bay, threading our way through Fox Islands Thorofare between North Haven and Vinalhaven Islands, and coasting safely away from ledges too numerous to name to visit friends in Tenants Harbor. To that end, I had taken great care to have the

Paper Is Where It’s At latest edition of the Navionics Platinum Plus cartography chip on hand before starting our cruise. With it, the MFD had been, for most of the voyage, a wondrous and accurate navigation tool.