Dead Reckoning — What is it? SOUTHWINDS once received a letter about Garmin and its electronic charts. It made me think about how the world of navigation on the seas has changed over the years. I think electronic charts and chartplotters all interconnected with GPS are some of the greatest things to come along. Why? Besides all the obvious reasons of convenience, it’s because just about everything to do with navigation is interesting to me. To be able to be in the middle of a sea out of sight of land and move across it or about it and get to where you want is an intriguing challenge that’s both suspenseful and interesting. To have all this mapped out on a little box in front of you adds to that intrigue. Then there’s dead reckoning.
There’s something about dead reckoning that I like even more.
The first time I made a crossing out of sight of land as captain was crossing the Gulf Stream from Miami to the Bahamas in a wooden 27-foot sloop. I had a compass, chart, knotmeter, watch and the traditional chart tools—nothing else to help me along besides what I knew, which was an essential part of it all (and no motor, by the way). It was dead reckoning. Plus it was nighttime—adding to the mystery and suspense of it all. We ran out of wind halfway across the Stream, which really threw us for a loop. But I had a pilot chart, which showed that the Gulf Stream was moving north that month (May) at about 2.5 knots.
As we made the crossing, I had plotted our position since our departure in the early evening every hour where I assumed we were, by creating vectors from what I knew about the wind, the current, our direction, speed and time. After the wind died to pure doldrums, we ended up drifting north for about eight hours, with our dinghy and its 2-hp outboard rafted to the boat helping us—barely—move east out of the main part of the Gulf Stream. We ended up eight hours later almost exactly where I had plotted us. As land approached in late morning, we were able to confirm our position. It was like a miracle.
I’ve never forgotten that night—and many others—as I cruised around the Bahamas for three months with just those same navigation tools and knowledge. Today, I often feel like making a passage out of sight of any landmarks with just those same tools guiding me. I would carry a GPS with me but not turn it on until we reached our goal. I just don’t know if I could do it. I don’t mean if I could succeed in getting to where I wanted on a one-day trip like the Gulf Stream crossing. I am sure I could. I just don’t know if I would have the strength to not turn the GPS
However, there is something about dead reckoning. It’s just not quite dead. Not in me anyway.
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