"5 Keys to Assymetric Speed"

Five Keys to Asymmetric Speed and Teamwork

By Kerry Klingler

Over the last 10 years, I have been campaigning boats with asymmetrical spinnakers. This article, which was also published in “Sailing World,” is about how to get more speed out of your asymmetrical spinnaker and be more comfortable racing with this type of sail. 

There are several premises that have proven to be fast on all boats, symmetrical or asymmetrical. Taking care of these details is the first step to finding down wind boat speed. The top of the list is always let the rig forward when sailing down wind. This one thing can have a huge effect on boat speed. First, off ease off your backstay; you might want to sight your rig after easing it to ensure you don’t ease it off too much and create a reverse fore and aft bend in the rig. In most boats, you will find you can ease the backstay a lot before this happens. On top of easing off the backstay there are other things you can do to help get the rig farther forward, such as using your jib halyard to pull the rig forward. After the Jib or Genoa comes down, the bowman hooks up the halyard to the tack fitting and grinds the rig forward. You will be amazed at how much farther forward the rig will go. On boats that use roller-furling systems on their headsail, you can’t tighten the jib halyard to pull the rig forward. My advice is to furl your headsail and then tension your jib sheet against your headstay to pull the rig forward.  On my J-80,  I would ease my backstay to the point where it was very slack. I would then tension the jib sheets to pull the rig forward, and that action would also pull the backstay tight. 

The second premise is that separation between the spinnaker and the mainsail is fast. The spinnaker trimmer’s goal should be to try to ease the sheet as much as possible and allow the spinnaker to lift and float away from the main. On asymmetrical boats, heeling the boat to windward also helps the spinnaker separate from the main. It also helps project the luff out to the side of the boat away from the main. This is why when you see the top boats in an asymmetrical fleet the whole crew is packed to weather down wind. It is also important pay attention to the trim of the tack line. I often wonder why racers adjust the topping lift on asymmetrical spinnaker all the time, but forget about the tack line on an asymmetrical spinnaker. The tack line has a similar effect as adjusting the pole height on a symmetrical spinnaker. If the luff of an asymmetrical spinnaker becomes too bouncy or hard to control, tighten the tack line. This straightens the luff, and moves the draft forward in the sail. I like to have the tack line a little tight for a spinnaker set or jibe because it makes it easier to fill quickly.  After you get going and the pressure increases in the sail, try easing the tack line. This allows the asymmetrical to float away from the main and drift to windward. I like to call this effect on an asymmetrical “opening the luff.”  When the luff opens, the sail lifts away from the boat to windward, the upper section of the luff are more pressured and the luff flattens in curvature slightly. This is OK because the spinnaker has pressure in it, and stays stable. It is achieving our goal of rotating to windward more and separating from the mainsail. A general rule for the tension on the tack line is the following:  If the tack line is angling off to leeward or if the luff of the sail becomes unstable, tighten the tack line:  If the tack line is angled to windward and you want to try to open upper luff, ease the tack line.   

The third key factor in downwind speed is mainsail trim. It amazes me how many sailors forget about the importance of the mainsail when sailing downwind. The first key is not to over-trim the main. I like to check trim by easing off the main until the luff starts to break and then trim it in until it stops breaking. Vang trim is also very important. In the NOOD regatta (our first regatta in my new boat) we were slow down wind. I couldn’t figure what the problem was. Then we experimented with a much looser vang and we started to find some speed. Keep in mind the mainsail it is still half the horsepower of the boat downwind. 

Weight placement is also very important to downwind speed. As stated before, get the crew to windward to project the spinnaker. Also try to play with weight placement, fore and aft. A number of the J-Boats have very full bows and like the weight forward down wind. This has proven to be fast in a lot of other boats as well. In Stars and Etchells you can often see a crewmember in front of the shrouds.  The goal in weight placement is to reduce wetted surface, not to plow the bow too much, and to keep the boat under control. In a Laser, keeping weight forward is very fast, but if you loose control of the boat, the loss can be great. 

Don’t be afraid to go out and practice, try different things. Use your Speedo or GPS to help figure the fastest way to sail. Also record downwind sailing angles. You will find them very valuable in a race for keeping track of shifts downwind. 

So, now that you have the general premises for downwind speed how do you organize you crew to maximize you performance. We use four key areas or positions that help in the division of labor on the boat. 

The first key position on the boat is the spotter/tactician. His job is to help with the following critical decisions: First is keeping the crew informed of the position and speed of your competition. The spotter provides the skipper with information about the boat’s speed and angle. The spotter also tells me things like we are lower or higher in angle and whether we are faster or slower. The spotter also helps with tactical decisions like keeping our lane clear and free from any wind shadows, and taking advantage of wind shifts and angles to the leeward mark. 

The next key position is spinnaker trimmer. The spinnaker trimmer helps the skipper sail the boat at the optimum sailing angle for the best VMG to the leeward mark. The trimmer should keep the skipper informed of the pressure on the sheet and sail. Helpful advice should be offered constantly about how much or how little pressure is on the sail such as, ‘I am losing pressure on the sail let’s try a little higher’ or ‘I have a lot of pressure, let’s fall off a little.’ The trimmer’s goal should be to keep the sheet as loose as possible without the luff of the sail breaking. On bigger boats, spinnaker trim should be worked as a team with the grinder and trimmer working together to keep the sail in optimum trim. 

As in any boat that sails downwind, there will be a time where you have to jibe. In asymmetrical boats, readiness is a key factor in attacking the racecourse. A second trimmer’s job is to make sure the boat is prepared to jibe at any time. On our boat, as soon as we complete a jibe we are prepared for another.  The key for a successful jibe is to make sure of the following: 1. The current spinnaker is free to run out smoothly and completely. 2. The second trimmer on the new sheet is in a place of location where the new sheet can be trimmed efficiently and quickly. 3. The new spinnaker sheet is clear of the bow pulpit and is up high on the headstay (around 6’ to 8’), ready for a fast trim.  During the jibe, the spinnaker trimmer on the old sheet stays with that sheet. His job is to make sure the clew floats to the headstay and then makes sure the pressure is off the sheet for trimming on the new jibe. The second trimmer, trims in as fast as possible and tries to get the spinnaker to refill as soon as possible. Right after the spinnaker fills, there should be ease in the sail for proper trim on the new jibe.  

The skipper’s job is to sail the boat to the fastest VMG to the leeward mark. It is his job to assimilate the information given to him by the trimmer and the spotter. Some skippers give the tactical decisions to a tactician, others make those decisions for themselves. The key is that boat speed and VMG are maximized. At the same time, you must tactically defend your position on the racecourse. 

In a race, we work together as a team to work the boat down the run. The skipper looks for constant feedback from the trimmer, spotter, and tactician. The trimmer is key in angle assessment and pressure on the sail. The tactician and spotter help keep the boat in an optimal position relative to our competition and the next mark. 

Other things to do that help:  Before a race get out early and get a good idea of the conditions and wind angles upwind and downwind. When going into a windward mark, ask yourself are you on a lift or a header? That will help you decide what tack you want to start the run on. Typically, you would want to sail on the headed jibe going downwind. Use a hand-bearing compass. It helps a lot on sighting the leeward mark and determining when to jibe to a mark. Try to make your jibes count. Each jibe is a loss in distance. Make sure you take advantages of the shifts, but don’t jibe just for the sake of jibing. In a J-80 on a one-mile leg two extra jibes would cost you at least three boat lengths. Work hard not to sail under the fleet, and keep your air clear, in asymmetrical boats, it is easy for boats behind to trap you and blanket you. 

Contact Author:
Kerry Klingler

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