Gear Shifting For Waves
Gear Shifting For Waves
Waves don't always line up with the wind. When this happens, your approach to each tack must differ. "From the Experts" from our June 2010 issue
The day before the first race of the 2009 Melges 32 Gold Cup in Fort Lauderdale, Fla., the kick-off to the class’s winter series, it blew 25 knots with big waves. By the first race, the wind dropped to 5 knots, with leftover 2-foot waves coming at 40 degrees to the right of the wind. This made one tack dead into the waves. Each time a boat slammed into a wave, it would then have to reaccelerate. A slight lift or a little more pressure pushed the bow just above the slamming angle and allowed that team to take off. Anyone caught in a light spot or a header stopped dead, as footing meant heading directly into the teeth of the waves.
Most venues don’t have such extreme differences between the wind and wave direction, but it’s not unusual, even on an small, inland lake, for one tack to feel considerably better, or worse, or simply different than the other. On one tack, the waves might be right on the bow, and you’re banging into them—“chopping wood.” On the other tack, the waves are pushing the boat sideways. Clearly, the wind and waves are not aligned, and if your boat is set up identically for both tacks—jib leads in the same place, backstay and sheet tension the same—you’ll be paying a big price in the speed department.
To be fast on both tacks, the most important sail setup considerations are depth and twist. There are other considerations, but these are the two most important ones and the two you can most easily adjust for each tack. I think about it this way: when the waves are not aligned with the wind, you need to set the sails up with more twist and greater depth on one tack.
Stay out of the woodshed
At the Gold Cup that day, port tack was right into the waves, so we set up the sails with twist and a fair amount of depth. If you only let the sheet out to twist the sail, you’ll loose too much power. That’s why we need deeper sails. Think of this as the “wave mode.” Here’s what you can do, from the back of the boat forward.
With the main, you want the clew to be further to windward and the top of the sail a little more open. Start by moving the traveler to windward. Ease the mainsheet a little to open the top of the leech, ease the backstay slightly to add depth to the top two-thirds of the sail, and ease the outhaul to kick the lower battens to windward a little bit and provide slightly more depth down low. On a boat like a J/24, you’re playing the backstay, traveler, and mainsheet—that whole loop—from tack to tack, so you’re always balancing those three controls. If it’s rough, you’re moving the traveler up, easing the backstay a little, and easing the sheet slightly.
If you were observing from behind the boat and looking at the sail, instead of seeing a relatively straight leech, as you would see in smooth water conditions, you’d now see the bottom corner—the clew of the sail—a little further to windward, the top of the leech a little more to leeward, and the middle of the leech in the same spot as it would be with a straight leech. The rougher it is, the more we need to bring to windward the bottom of the leech while opening up the top. Twist the leech off, and then make the sail deeper by easing the backstay, and you’ll have the same amount of power as the flat water setup except you’ll have a twisted leech profile that will be more forgiving.
Once the main is set, we match the jib shape to that. On the Melges 32, we kicked the jib lead forward an inch or two and eased the jib sheet. Moving the jib lead forward has the same effect on the jib as easing the outhaul has on the main—it adds depth to the bottom of the sail. Easing the jib sheet produced a similar result to moving the main traveler to windward—the top twisted off a little more. The upper jib leech was at about the same spot on the spreaders, maybe a little more open, but there was more overall twist, and the lower leech kicked slightly to windward. That “return” to windward of the bottom part of the jib shoots the wind back into the main a little more. If we can also inhaul a bit, we do that as well.
On the fast tack
After pounding into waves on one tack, the other seemed quiet and fast, so we set the boat up for the 5 knots of wind, but as if the sea state was flat: a straight leech for both the jib and main. Tighten the backstay and pull on a lot of sheet, tightening the leech, and lower the traveler. This is the “flat water mode.”
Remember, you want to keep the middle of the sail in the same position as when sailing straight into the chop, but close the top leech and straighten the bottom leech so that there is less overall twist. Jib leads on this tack should be at their flat-water position, and you’ll sheet the jib a little harder to straighten the leech so that it matches the leech profile of the mainsail.