When sailing upwind I have always had a problem determining if that boat on the other tack is on a collision course with me or if we will cross. Somewhere I heard about "making trees" and it was expained to me, but I did not get it. I found this website 2 years ago, read the info and still did not get it. I picked up the printed copy today, looked at the picture and the light went on. I figured this would be good info to share.
http://duckworksmagazine.com/r/vintage/ ... ensive.htm
If it is not obvious to you - as it wasn't to me: You are sailing upwind. Another boat on the opposite tack may or may not be on a collision course with your boat. The way I would apply it to model boats, and I would appreciate any info that clears it up further or makes it easier for me, you need to line up your boat, the other boat and a handy lighthouse on the far shore. No, but you do need something on the far shore to line up with.
As you sail along you would walk so as to keep your boat lined up with the lighthouse and take note of whether the other boat is "making trees", that is he is getting further ahead relative to the lighthouse which means he will pass ahead of you, or he is losing trees or falling back relative to the lighthouse which means you will pass ahead of him. And if the boats stay lined up then unless someone changes speed or course they will hit.
I will double the size of the bumper on my bow and give this a try. Heads up, Jack!
Scott