Cruising Cat: Performance Primer
Follow these performance tips to get the most from your cruising cat.
By Richard Woods
I’ve been sailing and designing catamarans since 1976. I’ve cruised tens of thousands of miles and have won several national titles in racing boats. Years of experience have taught me how to maximize sailing performance. For starters, nothing turns a cruising cat’s polar potential into sluggish real-time performance like excess weight, but this is only one way to ensure peak performance. Here are some more ways to tame your cat.
The old adage “Look after the ounces and the pounds will look after themselves” is never truer than on a multihull. A monohull, with a broad hull that cuts through the water, relies for stability on a keel that may weigh thousands of pounds. In contrast, a cat, with its two narrow hulls that skim over the water, relies for stability on its wide beam and is much more sensitive to the adverse effect of excess weight. The most practical way to keep a boat light is to avoid acquiring everything you have space for—a washing machine, for example. You’ll get the best performance from your cruising cat by ruthlessly removing everything you don’t need and, especially, keeping weight out of the ends and making sure the bows stay empty.
Drag is the enemy
It’s also important to keep the hulls clean; the extra drag produced by fouling is much more noticeable on a catamaran because of its high wetted-surface area. If your cat is equipped with daggerboards, adjust them. Always lift the leeward daggerboard when reaching to reduce drag and to keep the board from breaking. Lift both boards when sailing downwind; if it’s rough, put them halfway down to aid steering.
Catamarans have a reputation for being difficult to tack, but there’s no reason why a well-designed cat shouldn’t tack easily, even without backwinding the genoa. Usually the problem occurs when the commonly used big-roached mainsail is sheeted too tight prior to the tack. This causes the sail to weathercock and keep the bows pointed head-to-wind.
The trick to tacking a cruising cat is simple—just ease both the traveler and the mainsheet slightly before tacking. Handling will be easier if you eliminate any slop in the steering system and rudderstock bearings. And as is true of all boats, it’s crucial to have a comfortable seating position at the helm that has a clear view of the sails and approaching waves.
Since a big roach generates huge leech loads, it is essential to have a high-quality (often a triradial) mainsail. My laminated Spectra sails are not what you’d normally see on a cruising boat. Thinking that they were far too good to use cruising, I bought some cheap sails for my Atlantic crossing. Unfortunately, I found that they had stretched more after three months than the Spectra sails had after three years—proof that it doesn’t pay to economize on sails.
Battens that are too soft make the mainsail baggy. On almost all cruising catamarans it is essential to use rod battens. I do keep my loose-footed main quite full near the foot (around 10:1), but it gets progressively flatter as it goes up to the headboard.
Since batten cars cause drag that can result in the halyard tensioning only the top part of the sail, relying solely on the mainsail halyard to tension the luff doesn’t work. I use a 6:1 downhaul/cunningham on the main to combat that problem and any possible stopper creep.
I believe all proper cruising boats must be equipped so that one person can lower and reef the sails in any conditions, even downwind or in a gale at night. My boat has a big full-batten mainsail and swept-back shrouds. Most people think such rigs are a recipe for disaster, but that’s not necessarily true. To help tame it, I use strong, low-friction Bainbridge Sailman 2000 plastic slides. The real key to easy mainsail lowering is the mainsail downhaul, a thin line tied to the headboard. I lead it through alternate sail slides so that it doesn’t catch in the rigging. It’s tied off slackly to the gooseneck when the sail is fully hoisted. On releasing the halyard, I pull on the downhaul and the top part of the sail drops. It works every time. And if you have a full-batten sail, don’t go to sea without lazyjacks.
I have single-line reefing on my first two reefs. Using large ball-bearing blocks attached to the clew and tack rings reduces friction and chafe. Once the reef is pulled in, I connect the clew ring directly to the boom with a snapshackle. Cunningham holes above each tack point allow me to use my 6:1 purchase to tension the luff (this is much easier than using the tack hooks). When that’s set up I release the reefing pendant (made of Spectra) so there is no chance of chafe. I recommend using thin Spectra line for the genoa’s roller-furling line since it’s a line that must never, ever break. But it’s not just ropes that can chafe. Sails wear out fast if they are allowed to rub on the shrouds, so I have sacrificial strips of 1-inch webbing sewn to the batten pockets.
I always use a 4:1 preventer on the boom and a barber hauler on the genoa. Leech telltales and jib woollies are the best go-fast instruments you can have. The barber hauler provides just the right amount of jib twist. The preventer prevents dangerous accidental gybes and helps stop sail chafe.
The preventer also acts as a boomvang and is the only line on board that doesn’t have a stopper knot. If I have to release the vang in a hurry in order to gybe, this allows it to run out freely.
Many monohull sailors will be surprised to hear that I regularly fly a spinnaker when sailing without crew. Most spinnaker-handling hassles come not from the spinnaker itself, but from the pole—and who needs a pole when the windward hull often protrudes more than 10 feet to windward of the headstay? Despite the popularity of asymmetric spinnakers, I use a conventional spinnaker because I find it much easier to gybe. I usually cruise downwind with the spinnaker up, the mainsail lowered, and the autopilot on. It’s the only way to go. I do find it’s often easier to sail at 130 to150 degrees apparent than dead downwind.
The two golden rules for fast sailing under spinnaker are to keep the clews level and “if in doubt, let it out.” I don’t use a spinnaker sock to lower the sail as I find it frustratingly slow; instead, I trip the guy the old-fashioned way and pull the sail down into the cockpit. It takes a bit of running around, but I can always do this by myself.
Richard Woods sails two cats he designed—a 25-foot trailerable he keeps in the Pacific Northwest and a 30-footer he sails and winters aboard in the Bahamas.