Ok, I understand completely the differences between the two courses, but for those who don't wiki does a pretty good job. They can be checked out at:
http://en.wikipedia.org/wiki/Great_circle
&
http://en.wikipedia.org/wiki/Rhumb_line
So given the great circle is the shortest distance between two points on the earth, is that the best course for a cruising sailor to take? Obviously, on a day sail in the bay it doesn't matter, but what about the crossing from Panama to Tahiti? Now, the true great circle can never be achieved by a helmsman because it requires constant course changes at the helm that I don't think my
raymarine autopilot is ready for just yet. But you can approximate it with multiple waypoints on a regularly scheduled, say two day interval, course change.
I am a pretty fair hand with Mercator navigation, but I've not come across anything that talks about plotting courses using the great circle routes. Does anyone use these or is it almost strictly for airline pilots? If you do, please give me some guidance on how to determine the great circle route and how great a distance savings it makes in comparison to the rhumb
line in say, for example, the Bahamas to Bermuda run or Panama to Tahiti. Thanks, and look forward to hearing from you true navigators.
LW