December 8, 2015
Quantum Expert Answer
Following is a quick explanation of current effects on the racecourse. Yes, current changes the laylines on the upwind and downwind legs of the racecourse. However, current does not change wind direction. If the current is behind you on the upwind leg, you will have greater apparent wind strength. The sailboat will feel headed. The opposite applies if the current is against you. You will have less apparent wind and the boat will have more lift. If the current is behind you while sailing downwind, your apparent wind is less and you will have a header. Against the current on a downwind leg the boat will have more apparent wind speed and a lift.