More Headsail trim tips

Even though most genoas and jibs are smaller than the main?sails they team up with, your headsail should get at least as much careful trimming attention as your main. That's because a jib feels no disturbance from the mast and sails in an eternal lift created by flow around the main. As a result, your headsail provides more than its share of your boat's power.

For these reasons, it's impor?tant to work hard at finding the fast settings for your jib controls. Before every race, talk with the mainsail trimmer and helmsperson. Ask them to check out your jib trim and make suggestions. Talk with them about communication. Then follow the trim ideas here.

Trimming rules of thumb

Unless you are extremely confident about trimming the jib, stick with some proven trimming guidelines that can help you through almost any situation. Here are some things to keep in mind.

Calibrate Always use reference marks to help measure and record fast trim settings. Number the jib track holes for your lead position;put marks near your spreader tips to help gauge leech position; add an easy-to-see reference mark on your jib sheet; calibrate halyard tension; and so on. These are key for being able to reproduce your settings when you have similar conditions again in the future.

Communicate Since the jib trimmer must adjust sheet ten?sion continually for changes in the wind. keep communicating with the helmsperson and main?sail trimmer about what you are doing. If you ease the jib slightly to power up. for example, tell the skipper something like, "I can trim in two inches when you're ready." Or if you need more or less headstay sag, negotiate with the mainsail trimmer about how much to adjust the backstay.

Steering Use your jib trim (in conjunction with mainsail trim) to help steer the boat. If you want the boat to turn toward the wind. ease the jib sheet. This reduces wind pressure on the jib and allows the bow of the boat to head up more easily. One example of this happens when the boat gets a lift. If the jib trimmer quickly eases the sheet, it will be easier for the helmsperson to head up into the lift. Conversely, trimming the jib sheet helps push the bow away from the wind.





The 'groove' If your skipper is having a hard time finding or stay?ing in the upwind groove (which is common in shifty winds or bumpy seas), make the groove wider with a fuller and more draft-forward head?sail. Even though this may sacrifice some pointing ability, it should improve overall performance by increasing the time you are able to sail fast in the groove.



Sheet trim In general, trim the genoa sheet until the curve (twist) in the leech matches the curve in the deepest part of the main. If your jib has battens, it's usually good to trim the sheet until the top batten is roughly parallel to the boat's centerline. It may help to put a piece of dark tape on each side of this bat?ten so you can see it more clearly.



Trim guides There are two other good references for jib trim. When it's hard to see the top of the jib while racing, use the position and shape of the sail's foot. The distance from your spreader to the sail is also a great reference for duplicating fast trim settings.





Luff tension Like the mainsail cunnlngham. the jib halyard is not intended primarily for removing wrinkles so the sail looks better. The main purpose of the halyard is to adjust luff tension and thereby control (lie position of draft in the sail. Pull the halyard tighter to move draft forward and make the sail flatter; ease it to move the draft aft and make the sail fuller.

Speed wrinkles Sometimes the presence (or absence) of wrin?kles along the luff of the sail is a helpful guide for getting the right halyard tension. In light air, it's good to see anywhere from a hint to a multitude of wrinkles (except for laminated sails where you usually tension the halyard just enough to remove wrinkles). In heavy air, you usually need enough luff tension to remove all of the wrinkles.

Fore-and-aft lead Set the fore-and-aft position of the jib lead so the telltales on the windward side lift (stall) more or less simulta?neously up and down the luff. In many cases, the top (windward) telltale will fly a little earlier than the others. This is OK, especially in light or heavy wind. However, if it breaks a lot earlier, then move the lead forward. If it breaks later, you should definitely move the lead aft.

In-and-out lead On many boats you also have the option to move your leads inboard or out?board. A rule of thumb here is to move the lead as far inboard as possible without hurting the main?sail or slowing the boat. You want the lead farthest inboard in flat water and moderate wind: it will usually have to go farther outboard in light air, heavy air and chop.

Headstay sag The primary way to fine-tune the amount of power in your headsail is by adjust ing headstay sag. Use your back?stay (or running backstay) to increase or decrease sag and the overall fullness of the jib. The harder you pull the backstay, the less headstay sag you'll have and the flatter your sail will be. A straighter headstay also move the draft aft in the headsail, just as bending the mast does in the main.

Barberhauling On some boats, the existing jib leads are too far outboard, so you need to "barberhaul" the clew inboard by using the windward jib sheet (on one-designs) or a jib in-hauler (bigger boats). If the boat gets overpowered and you have to ease the mainsheet or traveler a lot. you may need to barberhaul outboard to keep the slot between the mainsail and jib from getting too closed.

Asymmetries The jib should normally be trimmed the same on each tack, but watch out for times when you have wind sheer or waves that aren't aligned with the wind. In these conditions, you will probably have to vary lead position and sheet tension from tack to tack.

Shift gears Like the mainsail, the jib needs constant adjustment because wind and wave conditions are always changing. When the boat feels good, try sneaking the jib sheet in another inch. If you're slow or in doubt, let it out. Remember the jib should work closely in con?cert with the main in order to have the best performance.



Keep track If you have a little time, it's helpful to keep a written record of everything you learn about your jib or genoa. Here are two ways to do this: 1) If you use just one jib design, make notes after each day of sailing. Record the wind and sea conditions, the set?tings you used and a note about your performance; 2) If you use two or more jib designs, organize your notebook by sail. For each jib. keep track of its wind range, hours used and optimal settings (lead, halyard, etc.) in various conditions.

The primary way to adjust the amount of fullness in your headsail is by changing headstay sag using the backstay, the runner or the mainsheet. Make your headsail fuller (i.e. increase headstay sag) in light air and waves;make it flatter (decrease headstay sag) in medium to heavy air and smooth water. Move the draft position forward when you need good acceleration (e.g. a tacking duel or waves). Move the draft aft in ideal pointing conditions. It's much easier to see the shape of the sail when you have dark horizontal draft stripes like the ones shown above.

No matter what type of boat you sail, there are three important trimming rules of thumb for your jib. First, you must trim the jib so it works with the mainsail. Second, keep adjusting jib trim to match changes in the wind and water. And third, the only valid way to judge whether you are trimming the jib well is by comparing your performance to that of nearby boats.