Balance

Rev. 11-16-2010

Not ying and yang. Not work and play.

Sails vs. keel and rudders.

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The usual practice is to locate the keel some distance behind the mast:

For example, my last boat, a Stiletto 27, had a dagger board several feet behind the mast, giving her good balance over a variety of sail choices and points of sail. Like most cats, she likes more main that jib up-wind, in part because a main is easier to feather in the puffs; she is well balanced in this configuration. Off the wind in a blow, she does better with more jib and a reefed main, steering easily and keeping her bows up. This is a common keel location; visit your local shore yard and observe that nearly all of the keels are in this general position. If the keel is long, the center is in this same spot.

But not the PDQ 32 or the PDQ 36, either. Both have the keels located several feet further forward than sailing balance requires, presumably to place them under the center of gravity, the best position for drying out. Should you run solidly aground on a falling tide, this is reassuring, but it doesn't help her sail; the center of lateral resistance is 2-3 feet further forward than it should be. The rudders are of a very efficient spade form, but they are small, can't make up for severe imbalance and will play tricks if you ask too much of them. They become inefficient at high angles of attack, piling on buckets of unseen drag, and then suddenly overload and loose their grip on the water entirely, allowing the boat to slew sideways with no more warning than the heavy helm you've been ignoring. Remember that the square riggers of old steered as much by sail balance as rudder; modern boats are not so bad, but the principles remain.

What does this mean to the sailor? What can be done? Well, she is still a very capable sailor, she simply asks that you handle her according to her nature. Because she has wheel steering, she only whispers; she won't talk loudly until the wind gets up, and then she'll scream all at once if you haven't been listening. Listen to the whispers.

To Windward. Because of this imbalance, she loves to round up and to go into irons if you let her. Don't give her cause. In lighter winds this is annoying and sometimes embarrassing; in strong winds she just won't sail in poor balance.

• Reef the main and jib together. It's tempting to just roll in a little jib, but taken too far she gets way out of balance. Lowering the traveler can help, but she'll be happier reefed.
• Keep the jib tight when the wind is up. Not over sheeted--it's hard to over the sheet the genoa because of the shroud location and chose reasonable self-tacker lead locations to avoid backwind--but not eased off and full. You are  trying to keep the center of effort well forward, to keep her driving and using the keel properly for leverage.
• Keep the traveler at or below the center. Never add too much pressure aft.
• Don't over sheet the main. The leach tell tales should always stream aft; they are the important ones on this boat. Don't worry if the windward tell tales lift.
• Drop the traveler a little on every tack, particularly if single-handing. It's tough to get the genoa sheeted back in fast enough to maintain balance, particularly if a sheet hangs-up. Without the jib she will tack nicely... and then turn right back head to wind, into irons. Pull the traveler back up once she has gained some speed.
• Remove all sheets from the self-tailing jaws of winches. There is simply too much delay, while the sailor unwinds all of this in an unexpected gust. Better, leave only 2 turns on the drum and place the tail in a conveniently placed cam cleat. More than 2 turns will often snarl into a tight override if eased quickly. Three or four turns are acceptable if a crewman will actively trim and only release with a hand placed properly on the drum (read any standard text, practice the method and watch your fingers).

Off the Wind. In light to moderate winds, do what you like and she'll still behave well enough. With no jib, she'll be very slow to bear-off, but little else is note worthy to the non-racer. In strong winds, 25 knots and up, the sails can easily over power the rudders, which can lead to a dangerous round-ups in big waves.

Keep sail on forward. Reef the mainsail first, then the jib. This has a number of benefits:

• Balance. With the effort forward, the boat will stay well balanced. Off the wind, the balance point of the sails moves outboard, because they are eased and also because the direction of their effort changes (less sideways and more forward). If you do not move the center of effort forward this outboard force will pull her around to windward, the helm can get heavy and she will try to round up in spite of your efforts at the wheel.
• Anticipate gusts and waves by bearing off. Gusts will move the apparent wind forward, causing the center of effort to move forward. Waves will push the transom and encourage rounding-up. Anticipate and steer off when you feel the beginning of a push. Expect that the autopilot will not do so well--it cannot anticipate or feel the rise of the boat on a wave front.
• Steer for balance. Dingy sailors learn to steer to keep the boat under the mast. The rule is unchanged when it gets wild. Always steer for balance.
• Reducing sail. Always roll-up jib by heading straight down wind first to blanket it behind the main. This will greatly reduce the chance of a jammed furler. Make certain you furler lead is fair; mine was badly misaligned by the installer. Immediately take a matching reduction in the main to keep balance. You may have to come up wind for this. Often I roll in a lot of jib, come in to the wind to reef the main, and then bear off and let some jib back out.
• If a rudder is either  lifted from the water or even significantly ventilated by the passage of a wave or excessive heel, half of the grip is lost.A round up is likely.

If these things are not done in a blow it is very probable that the rudders will simply be overloaded, the boat will spin-out, and the sailor find himself beam to the waves. Uncomfortable and disconcerting in brisk weather, and dangerous in bad weather. Yes, this is repetition, but I have heard so many tales of cruising sailors being surprised by this, I thought it worthwhile. Poor sail balance, it seems, is the most frequently underlying cause of a sailboat being "uncontrollable" in rough weather.

Wing and Wing. Perhaps the best way to go dead down wind in a blow. However, there are still some rules:

• The main should be reefed more than the genoa, since the main is larger and tends to have more projected area. This will result in better balance.
• Rig a preventer. This will "prevent" accidental jibes.
• The wind can build without your noticing it, since the ride is typically smooth. You may need to reef before jibing out of this rig.

 Heaving To: the practice of backing the jib while keeping the helm alee, for the purpose of parking the boat on a close reaching course, but with no way on. Often presented as a heavy weather management method, it is inappropriate to most multihulls; most "authorities" and most experienced cruisers will agree, although there are certainly some multihulls and some moderately poor weather circumstances where it can be just fine. Every rule has its exceptions, but they don't disprove the rule. The difficulty is that while monohulls can lay down on one side if a strong gust or wave strikes and relieve the pressure, where multihulls will at worst go over and at best give a rough ride. Heaving to places a multihull in its most vulnerable position, while running off plays to a multihulls strength by allowing the great width to provide a stable platform.

However, sometimes it is useful to heave to in mild weather, when the intention is only to park for a moment to fix or adjust something, or to simply hold station and wait for some reason. I'll do this fishing, sometimes, when I happen across a school of fish. Again, because of the keel-forward design, we must make adjustments. With the genoa up, the jib must be in tight, the traveler all the way down, and the boat placed nearly beam-on to the sea, rather than the traditional close reach posture. Generally, I find the wheel should be about 1/2 way over, but that seems to vary with the waves; it's not a very stable posture. Stay any closer to the wind and she simply rounds-up, maybe tacks, and takes off in a new direction. With the self tacking jib up, even if you pin it to windward, heaving to is unreliable at best, unless someone stays at the helm, and even then there may be nothing they can do. With even a small oscillation in the wind, she rounds up. There simply isn't enough sail forward.

This, from the PDQ manual:

Sailing Fast and Safe
 PDQ catamarans can achieve quite high speeds, even with displacement hulls. For the PDQ 32, various references predict top speeds in the 15-knot range. This speed potential leads new converts to multihulls into unreasonable expectations of cruising performance. To put things into perspective, note that the racing trimaran Steinlager has a maximum speed capability in the 30-knot range, yet she won the tough 1988 Around Australia race at an average speed of 9 knots. The fastest monohull of comparable length averaged 6 knots. Perhaps then, for planning cruises, it is best to expect an average for your PDQ no more than faster than an equivalent monohull.

While high speeds are possible under ideal conditions, such as an offshore wind with no waves, we consider this to be a stunt, and not necessarily good cruising seamanship. You should consider your PDQ 32 to be a good "9-knot boat". When the knotmeter goes to 10 knots, it's time to think about reducing sail. Above all, think about the quality of the crew's collective seamanship. Proceeding at a comfortable, safe and efficient pace with a happy crew is good  seamanship; scaring your crew or pounding the boat is not.

Sailing in Strong Winds
Sailing in strong winds in a well-built, well-equipped boat is one of life's greatest pleasures. There is, however, a point when strong winds become excessive. A major part of good seamanship is knowing when enough is enough. It is not possible to be precise about when certain evolutions should be carried through: crew skill and attitude, the stability of
the wind and the state of the sea will all affect vour boathanding decisions. In dealing with a high or rapidly rising wind, the goal is to reduce the wind's power on your boat and, by responding to changes quickly and smoothly, maintain everyone's confidence in your collective ability to deal with the weather.

Changes should begin to happen early in a rising wind, and should be seen as a progressive response to the wind's greater force. If changes are made in good time, no one becomes spooked, their confidence remains high and they cope better.

• De-power the main by flattening it with the outhaul.
• Raise the traveler and ease the sheet, so the main's upper section twists off to leeward. 

When do you reef? An old rule of thumb that's still worth remembering says, "reef when it first occurs to you." Do it before people start getting worried and do it before it becomes a struggle. As an indication, we have found that the boat is more comfortable when the first reef is taken at 20 knots true wind in flat water. When reaching, the reef can be put off until true wind speed is 25 knots.

As the wind rises:

• Take the first reef.
• Limit your boatspeed.
• Place a crew member on the traveler, ready to ease the main in gusts.
• Reef again to suit the gusts. (Sail loading rises with the square of the wind speed, so a 10-knot gust on top of a 25-knot wind will double the wind pressure.)
• Put a crew member on the jib sheet.
• Reduce sail to the absolute minimum.

We have found that this reefing combination maintains good balance:

• At 20 knots true wind: first reef in the main.
• At 25 knots true wind: second reef in the main.
• Over 40 knots: run off at 120" to 140" apparent wind angle under jib alone.

Be specially careful when traveling fast downwind as the boat speed can reduce a 30-knot blow to an apparently reasonable 18-knot breeze. If you are caught in squall while traveling downwind, use the main to blanket the foresails and get them down before rounding onto a reach. Speed is also discussed in the heavy-weather section, below.

Heavy Weather and Offshore Safety
One of the key factors to surviving bad conditions offshore is to keep your boatspeed down. In a monohull, this is generally done by lying ahull or heaving to. Neither of these techniques is recommend for the catamaran. With no heel angle to reduce the weight of wind on the mast and rigging and to reduce the lateral resistance of the hull and keels, the full force of the storm bears on the boat. This puts unreasonable stresses on the boat and increases the likelihood of damage or capsize.

If sea room is available, running before the storm is appealing, providing speed can be controlled and the crew is not too tired. The problem is that in extreme conditions, even with no sails up, the surfing speed down larger waves may increase to dangerous levels. This is the time to use a drogue deployed on 300 feet of line from the stern, balanced with a small amount of sail to give a steady speed for control. The article, Drogues and Sea Anchors by Ian Johnston and Cathy Hawkins (Multibull~M, ay-June 1989) provides more detail. If a drogue is not available, you can also trail the anchor line between the hulls, with the bight streaming aft in a huge U. The ultimate choice for surviving the worst is the parachute sea anchor. This is deployed on a bridle from the bow. If you are considering a uip offshore, please read, The Parnchute Anchoring System, published by Chiodi Advertising and Publishing Inc., Boston, iMA, USA, and follow Charles Chiodi's advice-"Get the system and don't leave the dock without it."

All this talk of heavy weather and survival sounds alarming. Remember that all accounts show that yachts of any type are
almost always tougher than the crew. Many have been abandoned by their crews, often with fatal results, and the yachts have been found later, afloat and intact. The infamous 1979 Fastnet Race was a good example of this phenomenon. Learn to trust your boat, and if the unthinkable happens, stay with it.

The Capsize Canard
"They do turn over, don't they?" is frequently heard from sailors with no experience of multihulls.
In his book, Rod Gibbons tells us that I,iovd's of London rates are the same for production boats, monohui )r multihull. He also reports that the Catfisher (70 produced in ten years) has a 100% safety record. Catalac and Prout also have superb safety records. The similarity of insurance rates authoritatively tells us that the wrong combination of wind and sea can visit trouble on any sailboat. 

Beyond the numbers, it's important to compare the experiences of people who suffer capsize in a cruising sailboat. A monohull's ballast may right it, but it must do so quickly or that ballast will take the boat to the bottom. Once a multihull is over, it tends to stay that way. This sounds dreadful until you note that the crew can live on' the overturned boat for week;. We've all seen the news photos of a crew waving from their upturned multihull--certainly these make better news
than a comparable calamity with a monohull. With the monohull, there is nothing left to photograph, whereas the multihull is often recovered to sail again.

Moreover, these photos often turn out to be racing superstars participating in a prestigious race, and that's a clue to the problem. Driven hard in steep seas, the boat stuffs its bows into a wave ahead and pitchpoles end-over-end. The probability of capsize, then, is determined not only by weather, but by the crew's management of the boat. In flat water,
wind can capsize a catamaran, but achieving this in a PDQ would require serious negligence or foolhardiness by the crew. The theoretical danger level for the PDQ 32 is about 28 knots of wind on the beam with full sail sheeted fore and aft. Failure to notice the risk would require an absurd level of inattention and the sails would probably rip before the boat went over. Chris White's The Cruising Multihull provides a good discussion of risky situations. Waves play a substantial part in the capsize of boats, particularly if any combination of shallow water or current combines with winds of gale force and above to produce breaking waves. Such conditions are dangerous, but a sensible crew can deal
with them, as described above. If a capsize should occur, however, there is one rule and one rule only: stay with the boat. With its combination of light weight, lack of ballast, closed cell foam hull sandwich and flotation
compartments, the PDQ 32 resists sinlung even when full of water. Crews that have been living on an upturned boat are not normally very happy with their situation, but they are often in reasonable health, having had access to food and water from the boat's stores. Compare that with the various fates meted out to monohull crews...

The closest encounter with capsize experienced by a PDQ crew occurred when a PDQ 36 was running at 22 knots under spinnaker in 30 knots of wind. The boat was dancing on its bows when the crew cut the sheet. This should not be regarded as conventional cruising behavior and the company will not celebrate your attempts to produce a more lively anecdote. 

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 Notes by SailDelmarva on the above: Since this was published, two PDQ 32s have been capsized: one flipped in the Bahamas while being sailed by a charter skipper of very limited expereince; the other was flipped by new owners, on their maiden voyage with their new boat, in strong gale conditions off the coast of northern California. Neither of these accidents occurred in experienced hands. Both were recovered. Hundreds are sailing.

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Good, as far as it goes, but more emphasis and explanation about WHY more jib area is required off the wind by this specific design is needed.

What else can be done to ease the balance? Move the rig forward? No, the deck reinforcement and main bridge deck beam preclude such changes. New draft-forward sails? Certainly some help, though owners with new sails have reported the same troubles. Move the keel? Oh yes, I have half a mind to saw it off and slide it back 2 feet. But that's major surgery to be sure.

Add some additional length to the keels? Yes, I think so, this spring when I haul the boat. The existing keels end with an unnecessarily blunt trailing edge with substantial forward rake (to shed keel wraps--I think I know enough about anchoring to avoid wraps). Adding a square foot of finely tapered trailing edge should be a minor project--I have a stock of pre-laminated FRP--and may give some benefit. I had also considered a small end plate, also to help move the center of effort aft, but I am convinced that could make groundings more serious, and that might be too great a price to pay. Still, I might add just a little, in part to brace the addition. I have some expereince with sort of thing: I modified the rudders on my Stiletto and was quite pleased with the result. If the result is not positive, a grinder will remove it in another 2 years with little fuss. I also figure a new square-top main with 3 reefs is in her future, but not for a few years. That may further move the center of effort aft, so I must plan for that.

But that will provide content for a summer post.

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Note: in 2015 I modified the keel to farther improve balance. Look for the post.