This article was originally published in October, 2000 at SailNet.
A few weeks ago, 18 1D35s from throughout the US converged on San Francisco Bay for their three-day National Championship regatta. Most sailors acknowledge the Bay as a heavy-air venue, particularly in late summer, and the Bay delivered as promised. Record-breaking heat in the region helped fuel a strong westerly rush of cool air off the Pacific, which sped through the Golden Gate every day and across the Berkeley Circle where the competition took place. Race managers from the San Francisco Yacht Club set three windward-leeward courses daily in breezes that ranged from 15 to over 30 knots.
The definition of heavy-air sailing will vary somewhat from one type of boat to the next, depending on the sail area, displacement, and stability of the design. Like many popular offshore one-designs and IMS-style boats, the 1D35 has a generous amount of sail area and relatively little wetted surface area in the hull in order for it to perform well in light air, but these boats are also endowed with tremendous stability to stay fast in a breeze. Even though boats of this ilk are powered-up in a way that means the crew must hike out in as little as eight or nine knots of wind, "heavy air" would usually be defined as sailing in a breeze of 20 knots or more.
The optimal rig setup for these conditions will obviously vary from boat to boat, but some general principles apply to all designs. More mast rake, for example, is a desirable feature in light air to promote weather helm, but should be reduced in a breeze where the boat will have adequate helm from the increased amount of heel. If the boat has running backstays, more load on them translates to a tighter headstay, which in turn helps optimize the shape of the jib for stronger breezes. More permanent backstay pressure will also help by tightening the headstay in masthead rigs, and by bending the mast to flatten, and thereby depower, the shape of the mainsail. On a 1D35—where the headstay is adjustable and there isn't a backstay—this stay should be maxed out to nearly 4,000 pounds of pressure in big breeze, with a little ease on the diagonal shrouds to allow the mast to bend.
|"Sail selection is simple—choose the headsail or spinnaker appropriate for the velocity in the lulls."|
Crew weight is also a simple concept—have as many people on the rail as the rules allow, hiking as hard as they can. For boats like the 1D35, it's particularly important to hike hard while rounding a mark (upwind or down) because this helps the helmsman maintain control as he or she turns the boat. The 1D35 crew weight limit is 1,400 pounds, which usually translates into eight or nine crew members on each team, and everyone, except the helmsman, and mainsail trimmer, is expected to hike.
Sail-trim techniques are a little more complex, but they're generally based on the principal of flattening the sail shape to depower the sail plan. Mast bend will promote flattening of the mainsail, and easing the sheet and letting the sheet lead back on the jib will allow it to depower by way of twisting off the leech. The mainsail should have the outhaul pulled on with maximum tension and the traveler should be dropped just far enough to leeward so that there's still sufficient pressure on the leech of the sail to give feel to the helm, but not so much as to cause excessive heel. If the traveler is to leeward and the mainsheet eased, using a little vang tension can keep pressure on the leech and prevent the sail from luffing. Then, as the boat sails up the leg, the mainsail trimmer constantly plays the traveler in the puffs and lulls in an effort to maintain a consistent pressure on the helm.
Driving the boat upwind in a breeze can be tricky, particularly in big waves, since the apparent wind can change constantly as the boat moves through the waves. The key is to have the mainsail trimmer balance the boat, with an ease of the traveler or sheet to gain speed after hitting big waves, and trimming in to gain more height when the boat is sailing faster in the smoother water. Just a quick word here about smooth water: Even in the choppiest conditions, there are patches of smooth water. It's a good idea to have someone on the rail keep an eye out for these areas and alert the helmsman so that he or she can take advantage of them by gaining a little height in those spots.
When tacking in heavy air, the helmsman should choose a spot where the water is relatively flat. It's important for the crew to be ready to move to the new rail as fast as possible and be hiking hard just as the sails fill on the new tack. Often it's a good practice for the trimmers to leave both sails slightly eased until the boat is almost back up to speed, and then fine-tune their trim, being careful not to over-trim the sails.Downwind Like sailing upwind, downwind performance is a matter of balance using crew weight and sail trim. In most boats, moving the crew weight aft will help keep the bow out of the waves and thereby give the helmsman more control. When the bow plunges into the back of a wave, the boat slows down, the apparent wind increases dramatically, and the boat can become unstable as the sails load up and the rudder comes out of the water. When this happens, the results can be very unpleasant and occasionally dangerous.
Because of the 1D35's light weight and oversized spinnakers, crews on these boats regularly sail with the spinnaker pole a little farther forward to keep the mid point of the sail in line with the boat's lengthwise axis. Sailing a little "hotter" (or higher) in this fashion produces faster speeds and better VMG numbers (Velocity Made Good) than squaring down deep off the wind, where the boat might be prone to rolling to weather, inducing lee helm.
For heavy air jibes, the best technique is to reduce the apparent wind speed by jibing while going fast on a wave, flicking the main across, and flying the spinnaker without a pole until the pole can be reattached on the new weather side. The 1D35 carries a long, carbon-fiber pole, and bow crews on these boats employ the end-for-end technique using lazy sheets and guys. Spinnaker trimmers make sure that the sheet-lead angle to the sail is kept high by pulling the tweaker (or twing) lines on hard, which helps to control the rolling motion of the sail.
Mark Roundings The best way to get around a mark in heavy air can be summarized in one phrase—be conservative! At upwind marks, it's fundamentally important to keep the crew hiked out while easing the sails through the turn and then get the spinnaker up. Another key to a successful spinnaker set in heavy air is to make certain that the lazy guy is not cleated during the set, and that the sail is not oversheeted or overeased when it fills. Using a permanent marker to put a set of marks on the line itself can help as references.
Everyone's heard that adage, "practice makes perfect." Well, it really rings true for heavy air competition. Having a few hours to practice sailing together as a team in these conditions does wonders for perfecting these techniques and for building confidence. Ideally you can do this just prior to the regatta so that dealing with the nuances of the waves and wind peculiar to that area can be mastered for when it counts.
So, back on San Francisco Bay, the 1D35 crew that proved most effective with its heavy-air techniques ended up winning the national championship. Dan Cheresh and his team aboard Extreme made a commitment to get to San Francisco three days before the regatta so that they could practice. They also configured their team so that they would have the maximum crew weight allowed. Then, when the regatta began, they coordinated their boat handling through the tacks, sets, jibes, and takedowns so well that every maneuver was close to perfect. They got good starts and executed good sail trim with the crew hiking hard enough to get to the weather mark first and lead around the course for most of the event. Cheresh and his team ended up scoring five bullets in eight races. You have to admit, it's hard to argue with success.
Beginning in Heavy Air by Dan Dickison
Surviving the Collision by Dave Gerber
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