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This Article Last Updated: Oct 14th, 2010 - 15:13:49
|Eric Doyle |
The most striking feature of sail plan of the star is the unusually large and powerful mainsail. A look at more traditionally designed yachts shows boats with much larger head sails paired with a conventionally sized main. One interesting trend which I have noticed is that the rest of the world is starting to catch up to the design of the star. We are seeing more and more boats come out with smaller jibs in relation to the main. From the International Americaís Cup Class to Mumm 30ís to Farr 40ís, everyone is starting to realize this configuration is fast, fun, easy to use and doesnít have to compromise the performance of the boat. In the star boat, much of our time and energy is devoted to setting up the mast and properly trimming the main and rightly so, as it is the primary driving force. However, the jib is important as well and in this article I will attempt to explain how different jib settings in various wind strengths can help improve the performance of your star boat. I know I run the risk of upsetting many crews who can probably trim the jib far better then I, but they can correct my mistakes in future articles of their own!
The first thing I look at when setting up the jib is the halyard height. This is critical to the lead position and must very precise and repeatable. On my boat the jib halyard adjustment is dead ended at a knot, either on the barney post or forward, which is just blown off at the leeward mark and allowed to rest on a stopper knot when sailing upwind. This way you donít have to worry about cleating the halyard exactly on some sort of mark when making the transition from down to upwind. Large adjustments to the height of the jib are made by switching to a different ball on the halyard at the mast exit. Try to remember which ball the jib is on for next time. If you are sailing an older boat, it is very important to have an adjustment to be able to quickly raise the jib high off the deck when running downwind. This helps to get the sail area projected higher up and helps keep the pole from digging in the water as the boat rolls to weather on heavy air runs. On my boat the tack of the jib is about 1 inch off the deck when going upwind. The foot of the jib just overlaps about half an inch on the deck almost all the way back to the clew. Not too much overlap though as this gives away needed sail area. Remember, as you raise the jib, the clew also goes up which has the same effect as moving the lead forward, and vice versa.
The lead position on your boat must be able to move both in and out and fore and aft. The in and out position is rarely changed and I will go over some special conditions where I like to try changing this later in the article. Normally it just lives at the 14 inch mark out from the center of the boat. We also have a mark 7 feet 2 inches from the headstay for the fore and aft position where we start the day. Small are adjustments made from there depending upon the conditions. I usually try to set the jib up according to the sea state: flat water-- lead aft and trimmed flat. In bumpy conditions-- lead forward and a rounder more powerful shape. In light to medium flat conditions, I donít mind having the lead aft with just a hint of a fold along the foot of the jib. The lead should be just far enough forward to get the leech of the jib to the mark on the spreader when at the maximum trimmed position. As the wind strength increases and the jib stretches more, the leech opens up and the lead has to go forward and the sheet has to be trimmed harder in order to get to the spreader mark. Only trim the jib to the mark if you feel the boat is going top speed. Keep it eased outside the mark in extremely light air, in sets of waves, coming out of a tack, off the starting line and at leeward mark roundings.
I always like to be able to see just a hint of wrinkles along the luff of my jib, especially in flatter water. The jib tack adjustment can be thought of like the cunningham on the mainsail. The harder you stretch the luff, the more the draft moves forward and the more the leech opens up. In flat water you want to be able to point high so the luff must be loose. This helps close the leech, so the lead must be aft in order to sheet hard enough to flatten the jib overall. If there is enough wind and the water is extremely flat, you might be able to try and sneak the lead inboard an inch or so. The telltale sign for this is when you feel like the luff of the jib is always soft and breaking because you keep trying to point the boat higher into the wind. In big waves or chop, the luff should be tighter to give the jib a more powerful, draft forward shape to drive the boat through the waves. This will also help keep the upper leech from cupping and closing down the slot. If the conditions get extremely windy, I have also seen people drop the lead outboard a bit to open up the slot without sacrificing any pointing. Contrary to popular belief, in windy conditions the jib must remain very full for several reasons. First, just the overall size of the main gives the boat too much power in the back and a full jib is necessary to pull the bow down and balance the boat. Second, the main is generally set up very flat and often breaking up a bit. The jib then becomes the driving force to keep the boat going forward. Often the waves are huge in these conditions and the boat will literally stop when pounding through them. A full jib helps the boat to power through the waves and to accelerate better after coming to a crashing halt. A very flat jib just makes the boat too hard to sail in these conditions.
Now, all these little tips are great for getting the final 2% of performance out of the jib in some conditions, but donít make it too complicated. Most of the time the leads are at the standard settings and the leech is trimmed right to the mark in the middle of the spreader. Clear, repeatable marks and settings are critical and good communication between the skipper and crew about jib trimming is also vital during the race. A little ease in a big set of waves and a little trim in a puff can go a long way toward grinding over that guy who started underneath you. I also like to do several tacks just after the warning signal to get in sync with the conditions and to give the crew the opportunity to see how hard the jib needs to be sheeted out of the tack and how long till he can sheet into max trim. Take some time also to practice some boathandling, but with an old jib as this type of practice can shorten the useful lifespan of a new jib considerably. One afternoon at the beginning of the season to shake off the winter rust can go a long way. I like to go out by ourselves just do transition drills from upwind to downwind and do some leeward mark roundings. This helps reduce the chances of pulling the mast back with the jib halyard all the way up and stretching the luff of your brand new jib as tight as a drum, or the ever damaging wrapping of the jib around the headstay. Ouch!! It is also nice to come into the leeward mark on port tack and have the confidence to jibe right at the mark and turn upwind without a hitch.
I try to keep the trim on the boat as simple as possible. Getting the boat set up before the start and then trying to go the right way will win more races then changing the jig leads ľ of an inch. But, just as you keep an eye out for windshifts, always keep an eye out for changing conditions which require a change of trim.
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