Tuesday, October 25, 2005

Shifting Gears in Light and Variable Wind by Rich Bowen

The key to keeping the boat moving in light winds is clear communication between the helm and the trimmers.
We've all heard people use the term shifting gears when talking about sailboat racing. Surely a lot of folks scoff at first when they hear this. There's no transmission on a sailboat. Sailboats are slow and they lack the kind of gear-shifting we're accustomed to in cars. But actually, shifting gears on the racecourse follows exactly the same concept as it does in cars. Put yourself in the following scenarios, and you'll understand how best to react to the hills and straightaways out on the racecourse.

Remember, on sailboats, one of the most important factors when it comes to shifting gears—especially on larger boats—is communication among the speed team, that is the trimmers, the driver, and the tactician. All of these people need to be aware of what is happening or what the goals are in particular situations. For instance, the tactician needs to know if the boat is at max trim in a close, port-starboard situation, because if it's not, he or she may want the sails sheeted to cross the other boat, or eased out to duck it.

"Having the trimmer provide feedback to the driver and tactician while making minor adjustments can make the difference between preserving your spot among the leaders and sucking bad air in the cheap seats."
Here's the scene: It's early morning and the crew is gathering at the boat on Day One of a regatta. The tactician arrives with the weather report and gives everyone the low-down on the expected conditions—light and variable. Someone says 'We'll need the entire newspaper and a Sports Illustrated to make it through the postponement.' Look on the bright side, it could be raining.

The first critical adjustment for these conditions—tuning the rig—should take place even before leaving the dock. Your boat's tuning guide (obtained from your sailmaker, class association, or boatbuilder) and whatever notes you've taken while practicing should indicate the best rig settings for light air, so make sure you've got this covered. The next call is which sails to use. Depending on what kind of boat you are campaigning, you may have the latitude of selecting different headsails and downwind sails for the day's activities. Obviously for a light-air day, you should think about bringing an appropriate spinnaker, not the heavy air 1.5-ounce kite. And you might want to leave any heavy air jibs on the dock and instead bring the light jib and an AP (all-purpose headsail) if that's an option.

Now let's fast-forward to the start. The brain trust in the back of the boat has gotten your team off to a perfect start, you've got a clean lane at the favored end with full speed on your way to the favored side of the racecourse. In these light and variable conditions, the headsail trimmer is always on the job, sitting in to leeward, at the winch, with the sheet in hand, not in the cleat or the self-tailer. It's important that he or she constantly provide feedback to the helmsman and tactician while making minor adjustments in sail trim according to the demands of the situation. This can make the difference between preserving your spot among the leaders and sucking bad air back in the cheap seats.

As you sail along, your boat speed starts to drop and the headsail begins to luff slightly as the angle of heel begins to decrease. All these are signs that the apparent wind is going forward, meaning that you're sailing into less pressure, which is like starting to climb a hill in a car. OK, it's time to downshift. The jib trimmer or tactician should communicate to the rest of the afterguard that the boat is sailing into less pressure. Then, working in unison with the mainsail trimmer and the driver, he or she can begin to get the boat moving as fast as possible.


It's those subtle adjustments you make to the trim of the sails and the trim of the boat that can keep your boat moving through even the least inspiring zephyrs.
Generally, the initial reaction in these situations is to begin easing the jib immediately, knowing that the sail is now sheeted too tight for the new wind. The trimmer should ease the sail gradually so that it doesn't cause the driver to over-steer and essentially chase the tell tales down in order to find his or her groove. So ease the sail just until the tell tales start flowing again. A typical exchange in such a situation might go something like this:

Trimmer Tim: "We're losing pressure and slowing down, I'm going to give you a slight ease."

Driver Dave: "OK, keep us moving."

Tactician Tina: "Yeah, we'll need the speed because we want to tack in the next two minutes."

Trimmer Tim: "All right, I'm eased three inches and the speed is beginning to come back."

In extreme situations, where the wind has dropped drastically, you may want to ease the headsail halyard tension and the backstay as well as move the sheet lead forward. If you make these adjustments, make sure all of this is communicated to the driver and tactician. Knowing how much the boat has slowed down and how much the wind has decreased will determine the amount of ease needed to get the boat back up to speed. Once the boat is going well enough to resume normal upwind angles for the new conditions, and the tactical situation permits, the headsail trimmer should begin sheeting in and telling his cockpit partners that he's getting it back to maximum upwind trim.

The second possibility in these conditions is an increase in pressure, which would be like starting down a hill in a car. An increase in pressure, when racing upwind, usually allows a boat to sail closer to the wind. When building pressure comes down the course and gets to your boat, the outer tell tales may begin to lift, indicating that the course your driver is steering is too low. There's usually about a two-second delay before the crew on the rail begins to yell: "You're heavy, head up!" Remember, a big change of course made rapidly in light conditions will result in a dramatic loss of boat speed, so don't let the driver over-steer in these situations.

Before the driver begins heading up, keep in mind that when the outer tell tales luff, it's also an indication that the sail might be over-trimmed. The headsail trimmer (sitting with the sheet in hand, ready to react) should communicate to the driver that he or she will ease the sail three inches, or whatever amount is necessary, to make the tell tales flow evenly again. This is when you start shifting into a higher gear to go down the hill. As the boat speed begins to increase, the driver can begin to head up toward the proper upwind angle and the trimmer can begin sheeting the headsail back to max trim. Remember, communication with the driver while sheeting will keep that person from heading up too far. Once again, the headsail halyard and backstay tension may also need to be adjusted for the increased pressure.

If there's one thing you can be sure of out on the racecourse it's that the wind is constantly changing, so you have no excuses for not practicing the technique of shifting gears. The next time you're out sailing upwind in light air, take a moment to sit down to leeward and start making some subtle adjustments in sail trim. If you pay attention to the tell tales and the boatspeed while you're doing this, you'll eventually develop a feel for how much ease is enough when the wind drops and how much trim is necessary when a puff hits. Good luck and good sailing.

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