And after:
From the photos you can actually tell that I washed the cabin wall in the process :-) I forgot my electrical tools, so I have to come back tomorrow to make the compass light work - and check deviation.
Is compass important for racing? It is! And not even for finding the way (which in a long race may not be obvious), but for finding out when to tack.
Everybody knows that you tack on a header, right? Let's say you are sailing close-hauled on a starboard tack and the wind changes direction so that it now blows 10 degrees more from the left. If you want to continue on starboard tack, you would have to bear away 10 degrees - you would be headed 10 degrees - you would effectively lose these 10 degrees. But if you tack, you will be lifted 10 degrees - you will effectively gain 10 degrees. A header on one tack is effectively a lift on the other tack. It is absolutely essential to know if you are being headed or lifted.
How can you know? First, you concentrate. Second, you watch the telltales, and adjust the course to maximize boat speed. Third, you notice changes in direction. This is where the compass comes in.
By looking at the compass, you can tell not only that you are changing direction, but by how many degrees. Is the wind shift instantaneous or swinging? As Mark Russel explains in his "RYA Tactics", the nature of the shifts affects the strategy - if the shifts are swinging, you should only tack after you are headed below the mean direction. I haven't repeated his math, but here is the illustration. Orange wins by adopting this strategy, while Mauve tacks immediately on each header. Pink gets it all wrong by tacking on lifts.
If you are interested in tactics, this is a great book - what you see here is just one page from the first chapter! And it may very well prove useful this Saturday - current forecast from Meteo Blue predicts a strong Bise.
I don't mind a strong wind; I just hope they won't cancel the race if they think it is too strong...
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