You've had an adventurous trip, you've seen some new ports and now you're nearly back home. Less than a mile to go, you can see the harbour entrance so let's stop following the line on the chart plotter and head straight in …
You could just have made a big mistake. I very nearly did!
I admit, as a skipper, I'm a bit green (especially when the waves are in from the side!) but I reckon anyone could get into trouble in waters with a decent tidal stream.
I started sailing nearly three years ago, bought an old 26' bilge keel cruiser, went to the boat show and purchased a few useless things but I did also buy a little Garman chart plotter which I love.
I just put in the waypoints, join them up and I've got a red line to follow. Yep, I know they could switch off the satellites, its memory could get nuked by intense magnetic radiation, or I could accidently drop it over the side.
With all those potential problems it's still got a 99.9% better chance of getting me to where I want to go than me and my dividers - but that's another story.
It took me a while to realise that when I blindly followed the red line on the plotter I would arrive at my destination even though I could see the place I was going to over on one side or the other of my heading. It looked like I was heading straight for the cliffs but I would end up in port!
I threw my all my brain cell(s) at the riddle and came up with the solution: to helm the boat so it stays on the red line on the chart plotter you are continuously adjusting for tidal stream.
QED - you are in fact skewing down the line - it just looks like you are going somewhere other than your destination. If you are doing 3 knots and the tidal stream is doing 3 knots into your starboard beam then your destination will appear 45 degrees to port.
So when you have the bow pointed at that well known haven, eyes looking forward to the harbour entrance, mind relaxed and thinking 'Stella' or 'Old Original' you are forgetting that for every 100 meters forward you travel you are moving 100 meters to port.
This is not at all obvious when you are just looking at your destination in your euphoric dream. It was only the sound of waves breaking on the rocks that made me see how close we were to the rocky shore.
If the sea had been calmer or if it had been darker …
There for the grace of God …
