crew weight 368
When sailing in light air and chop, conventional wisdom says to keep the crew weight together to minimize pitching. But if you watched the U.S. Olympic Yngling team of Sally Barkow, Carrie Howe, and Debbie Capozzi sail in light air and chop, you may have seen something different-they weren’t always bunched together in the middle of the boat. Rather, they were spread out, and they were going fast. Dave Powlison spoke to their coach, James Lyne, who explains what they were doing and why.
Rethinking weight placement in chop to deal with pitching was a matter of revisiting old lessons. I remember talking to Charles Curry, who had won the Finn silver medal at the 1952 Olympics, which was well before I was even born. He told me that, in the old days, when his Finn started pitching too much, he would fill his bow tank with a bucket of water. Here was a silver medalist, who, at the time, was one of the world’s best singlehanded sailors, and he was spreading out the weight instead of consolidating it. I was too young to clue into it when he was telling me this, but it’s a story that stuck with me.
Builders do all they can to centralize weight to create a relatively good center of gravity, linearly, which helps reduce pitching. However, when the crew is a big portion of the all-up weight, such as the Yngling, with 440 pounds of crew weight on a 1,430-pound boat, you’re talking about a fairly significant ability to change the boat’s dynamics by moving the crew around. Just because the wind is light and the chop is up doesn’t mean you always want to consolidate crew weight.
The key is to look at frequency, how quickly the boat is pitching, and amplitude, identified by the arc through which the top of the mast moves. Then the question becomes, which is causing the biggest performance loss? Is it that you’re pitching too fast or is it that the radius you’re going through is too big?
If we’re pitching too quickly, and frequency is the problem, we start spreading the crew, slowing the frequency and allowing the flow to stay attached to the sails. At the same time, we’re trying to lower our center of gravity. Upwind, we have the jib trimmer, Debbie, lying on her on the cockpit floor, with her head back around where the rudder post is, looking straight up at the jib, which is a pretty comfortable position compared to the standard jib position on the floor just aft of the cuddy. Meanwhile, Carrie, the middle crew, who does a lot of the tactics, lies on the deck or on the cockpit floor. For Sally, the skipper, the choice is usually to sit either on the side deck, which isn’t great in terms of lowering the center of gravity, or on the cockpit floor, which doesn’t give her a great visibility. Because the class rules require that each boat carry a bucket, the third option is to put the bucket on the cockpit floor and have Sally sit on it, which gets her weight lower but still allows her to see.
Once we start sailing in 10 to 20 knots and chop, we no longer care about frequency because we’ve got flow around the sails. We want to limit pitching as much as possible. Now we begin squeezing everybody together. We also start moving the weight aft, but still together, because the aft section of the boat has quite a bit more volume than the forward sections. Moving aft a little stabilizes the boat quite a bit. In the Yngling, it might be only six inches aft. But moving 440 pounds six inches has a significant effect, especially on a 19-foot boat.
Downwind, our most significant departure from traditional crew weight placement comes when we’re sailing above displacement speed. In winds of 18 knots or more, while the rest of the world sails with the forward crew, just at the front of the cuddy, you’ll see Debbie on the aft deck, kneeling behind the traveler. That represents a 12-foot movement of a 132-pound crew. The rest of the world sees us and thinks we’re crazy. But we think it’s faster. Here’s why.
Like many boats, the Yngling has a lot of volume just in front of the mast and a lot of rocker. Once you’re above displacement speed and you have the boat in a slightly bow-down to level position, you end up pushing a huge volume of boat through the water. There’s so much volume in the bow that it’s making a bow wave that resembles what might come off a super tanker. But the boat has this lovely flat aft run, and if we just rock the boat back, all of a sudden we’ve taken all that volume out of the water up forward. The windier it is, the more aggressively we move Debbie aft. She’s usually at the back of cockpit when the wind gets to around 15 knots, and once over 20 knots, she’s definitely on the aft deck.
But it’s not like she is parked on the back deck whenever the breeze is on. Even in 20 knots, Debbie will go onto the back deck when the boat starts riding a wave. Once the boat starts to slow and becomes a little stern down, Debbie goes forward to keep the boat level and keep it going down the wave-like a surfer hanging 10. She wants the boat to keep sliding. She’ll come quickly forward, probably all the way up to Carrie, the spinnaker trimmer-maybe 6 to 7 feet-to try to keep the boat going down the wave. As soon as the boat’s got that little surfing kick down the wave, she’ll go all the way back again. In the 12- to 16-knot range, she does a lot of traveling from the back of the cockpit to the front of the cockpit, which is about 8 feet. She’s thinking like a surfer: when the boat’s just coming up the back of a wave and starts to get a little bow up, she moves forward. As Carrie pumps the spinnaker to catch a wave, Debbie rapidly moves aft. The goal is to get the boat into the right attitude-bow down-to get on the wave.
Is it legal? At this level, we’re always sitting in the gray area. But it’s not ooching, which is a sudden forward movement; she’s not standing up and pushing on the mast or the cockpit combing or anything sudden like that. Instead, it’s a very smooth movement back and forward. Yes, she’s moving, and she’s imparting energy into the boat to kick down the wave, but she isn’t trying to release the boat. Instead, she’s moving smoothly to keep the boat’s attitude correct. Obviously, there are times when she’s really imparting energy into the boat to get it to surf, but that’s the gray area. We’ve never been flagged for these movements.
Debbie’s positioning also helps Sally steer. You’ll see Debbie standing up and shifting her weight from foot to foot or, if she’s kneeling on the back deck, shifting her weight from one knee to the other. Having her stand is actually an advantage because it raises the center of gravity and imparts quite a bit of energy to the boat. So when she shifts her weight to her leeward foot, the boat really rolls up. At times, Debbie will stand in the cockpit in a surfing stance to help steer the boat up and down.
Everybody thinks we’re crazy, but Sally really likes it. Just after she rides a wave down and Carrie has just pumped the spinnaker, the boat rolls to windward. At that point, Sally needs help flattening the boat and turning it back up. If you do it all with the rudder, it’s very slow. So right after the boat rolls down, Debbie steps to the leeward side, and the boat heels to leeward and turns up. Try it, especially if your boat is relatively fat in the middle and fine in the ends.
Downwind in sub-displacement conditions, especially in flat water, wetted surface is the biggest impediment to hull speed. We’ve found it fastest to get crew weight as far forward as possible. Debbie will lie down on the foredeck, head on the forestay. That keeps the center of gravity low, which is important even in light air, where any increase in side-to-side roll flattens the spinnaker and destroys the flow. Now we want the boat’s fine forward V-section in the water and the flat U-shaped stern section out. We’re losing waterline, but that’s not an issue because we’re at sub-displacement speeds, meaning we can’t even get to our theoretical hull speed. If we reduce our wetted surface area 30 percent, that’s huge. We can reduce a certain amount of that with heel, but that can also affect rudder angle, and that depends on what Sally wants. You sometimes see boats sailing downwind heeling to windward or to leeward, and the helmsperson is clearly feeling a lot of pressure on the helm. You can make more gains in wetted surface reduction by moving the weight forward.
How can you tell when to change weight placement-when you’re under or over displacement speed? Look at the boat’s wave train. Are you starting to create a bow wave? Are you starting to create a stern wave? Are you starting to get a trough between the bow and the stern wave? Are the bow and stern wave relatively pronounced? If so, you’re above hull displacement speed. When below it, there’s just a ripple where the bow parts the water, and you can just see a few little eddies in the back where the foils and hull have gone through, but there’s no appreciable wave at all.
In Olympic sailing and America’s Cup sailing, we spend a lot of time two-boat testing to find the crossover points for weight placement. That’s what a lot of the Olympic testing is all about-very small variables just to find out where that crossover is, sort of like the finishing touches to a painting. It doesn’t take much, about 2 knots, where you go from being below hull speed to above it, and all of a sudden, it’s 180-degrees flip-flopped.
That’s what makes it so interesting.