21 Nov 09
Following contour lines is one of my favourite means of navigating close inshore. If the lines zig zag around a lot, or are dotted, then they are probably unsuitable.
So, find a suitable contour line that is as close to the shore as you want to be, and safe. Add the height of tide for the time of day you are sailing, and keep that figure showing steady on your depth gauge.
If in doubt – go out.
At anytime, of course you can change to a different contour line. However, always add the height of tide above CD; otherwise, you will not be where you think you are.
How else?
Well, GPS, waypoints, routes, tracks and x-track error etc., need no explanation here. Other, traditional stuff like vertical sextant angles, transits, constant bearings, etc., all have their uses depending on the situation.
Use whatever you are confident with to make a safe passage.
Charts plotters deserve a brief cautionary note because we tend to take their accuracy for granted, when, as I found out last summer, they can certainly be adrift. Picking my way up carefully up the River Dart towards Totnes, in my 2m draught boat, required a fair degree of concentration. So it was a little distracting to see my Chart Plotter ‘accurately’ positioning ‘Yacht Anni Frind' in among the grazing sheep a quarter of a mile to the east for much of the upper reaches!
I’ve enjoyed writing this item about our cruising interests, and if you should see me around do please say hello. I sail a Bavaria 30 named ‘Anni Frind’, my fourth boat. She is berthed in the Weymouth and Portland Borough Council marina adjacent to the North Quay entrance.
