Win more races
Call Us: Bill Fanizzo 312-218-0339

Sailing in Current

Sailing in Current could be costing you 50 seconds/mile

CurrentSailing in current can be a blessing or a curse. Current can approach 10% of boatspeed. If it’s going the same way you are, great. If it’s going the other way, bad news.

If you don’t know where and how fast the current is going, you could be losing 50 seconds/mile and not know it

Another thing to realize is that current is much more variable than you think or current tables tell you. Back eddies, wind effects and harbor outflow make current do things you would never believe. And on a scale of minutes and a few hundred feet.

Having a real-time current readout is the only way to monitor it and use it tactically

Calculating current requires both GPS and paddle/compass input.

GPS based systems cannot calculate current

Learn more about the importance of paddles…

Current also changes true wind. This can cause confusion because, contrary to perception, performance (relative to the water) is not affected by current. There is no “lee-bow effect”.

Learn more about the lee bow effect myth…

How the Ockam system helps with current

CourseWithCurrentHere we see the OS5 racecourse page with the current status enabled. This current status feature is available on several pages.

At the boat, the blue arrow is the current speed and direction. On the right is the dCur arrow which is the amount of current going in your direction. In this case, it’s almost a knot against you (red arrow). If it’s in your favor, the arrow will be green.

In upwind sailing, the 90 degree difference in heading on the two tacks will change the current’s effect on your performance. If you know this, you can choose when to tack to increase its help or neutralize its effect. In this case, tacking to starboard will change the 1 knot of hindrance to 0.2 knots of help. Knowing this can help in your decision about tacking.

By the way, that “Ready to tack” banner is a report from the tack logger, which reports your tack score for training purposes.


Leave a Reply

WordPress Appliance - Powered by TurnKey Linux