On Mon, 19 Jan 2004 17:40:49 -0500, Gene Kearns
wrote:

Considering that there will most assuredly be some sort of outside
influence working on your desired track, the 270 given by the GPS, you
might be forced to *steer* (by compass heading) a different number,
say 260 or 280. Your boat will crab into the wind/current much the
same way some dogs seem to run sideways.... but the *path* of your
vessel should be the 270 degrees.
============================================

Here's how I do it for what it's worth.

1. Observe course to waypoint on GPS. (Waypoint Bearing)

2. Steer same course on compass and observe Course Over Ground (COG),
or Course Made Good (CMG) for a short time (maybe 30 seconds).

3. Adjust compass course until COG/CMG equals waypoint bearing.

4. At this point the boat should be traveling in the right direction
to go directly to the waypoint with all necessary corrections built in
for current, compass error, wind, etc.

5. Re-check COG/CMG vs Waypoint Bearing periodically and adjust
compass course as required.

There are other perfectly valid techniques of course, such as setting
a "from and to" route and observing cross track error. This is
basically what the "highway" display is doing in graphical form.

Another approach which I sometimes use with my computerized charting
software, is to lay out the entire route the night before. This
creates course lines on the mapping display and you can watch the boat
move along the course out of the corner of your eye, making steering
corrections as needed. After you've found the rignt compass heading
to maintain the course, you just need to double check progress every
minute or so.