Join Date: Jun 2000
Location: CT/ Long Island Sound
Thanked 34 Times in 33 Posts
Rep Power: 17
A magnetic compass can do just about all the same things the digital compass does on the race course. They are NOT just for steering to a course. We routinely use ours to track headers and lifts. If we start out on a starboard tack heading at 90º and after a while find that we're only able to make 80º on that tack, it means the wind has shifted to head us. In order to sail the shortest course to the windward mark, we should tack onto port. When we tack, we note the course we're able to hold - probably around 170º. If the wind changes to head us down to 180º on port tack, it's time to tack back to starboard. Conversely, the wind can shift to lift you as well. Take advantage! If you're hiking out, you can use the lubber-lines to see the relative change of heading; you don't have to be looking from right behind the compass to use it. You can also use the compass to see if you're gaining on competitors by seeing if their compass bearing relative to you is changing. Sight on their mast for the most precise measure. The compass is also useful for finding out which side of a course is favored. If you can see the windward mark, point the boat towards it and note the compass heading. Then point the boat directly into the wind and note any discrepancy. Few race committees are able to set marks directly into the wind every time; the side the wind is coming from will be the "favored" side of the course, all else being equal. Head to that side if you can. Knowing how high you can point on each tack (in degrees) alerts you to changes in wind direction after you've rounded a mark, so you can take advantage of the shift. Compasses are especially useful in 'round the buoys racing and a lot cheaper than a GPS.