Heavy weather and survival conditions
First, let us make the distinction between heavy weather sailing and survival sailing. Heavy weather sailing is done in full control of your circumstances and ability to manage your vessel. Survival is when you pass that point and must take action to preserve life and property, a topic discussed later in this article under the heading of Drag Devices.
Historically, many situations that would have been survival situations in other craft were just heavy weather sailing for cruising catamarans. A classic story by Robin Knox-Johnston was published in Cruising World. It is his account of sailing his catamaran through Force 12 winds. There are other similar experiences that support the notion that keeping the vessel underway is a good survival tactic.
Little has been written specifically for survival situations in multihulls. The basic reason for this lack of literature is the astonishing safety record compiled by ordinary sailors in “off-the-shelf” catamarans. At the time of the famous Fastnet disaster, of which volumes have been written, there were two cruising catamarans in the vicinity. They were shadowing the fleet as unofficial entries when the racing fleet sailed into a serious storm. The carnage caused by the storm was so great that a “Committee On Safety From Capsizing” was formed. Their purpose was to design a minimum stability formula for ocean racing monohull yachts. The weather that was a disaster to the Fastnet fleet was considered merely “beastly weather for sailing” by the two adjacent catamarans.
During the tragic “Queen’s Birthday” typhoon off New Zealand, the two catamarans showed that even with an aging and somewhat handicapped short crew they could provide predictable and adequate safety. There are numerous stories of catamaran crews simply furling all sails, lashing the helm amidships and going below to wait out the storm while their cat bobbed around looking after herself.
Knowing when to reef is the most important skill to develop for heavy weather sailing; next comes sail shape and sheeting angle. There are a few generalities that will help you get started learning about heavy weather sailing tactics:
- As the wind increases, move the sheeting point to leeward. This is one of the best features of multihull sailing. Multihulls have a wide sheeting base which allows a greater angular choice for sail trim than narrow boats. Ease off the traveler to move the main to leeward and use an outside rail attachment point, stanchion base, toe track and car to move the jib to leeward. To further flatten the mainsail tighten the main halyard, outhaul, downhaul and running backstay as necessary.
- Allow more twist in the sails as the wind strengthens and reduce camber (flatten) the sails. This is achieved in the main by slacking the main-sheet and in the jib by moving the sheeting point aft.
- Reduce sail. Most multihulls are just as happy with reduced sail and you will be surprised how little speed you really lose. By reducing speed you will also greatly decrease the loads on rig and structure, diminishing any chance of fitting failures or torn sails.
- Learn to use a barber-hauler (see glossary) to control your jib. A barber-hauler does not need to be a fancy multi-part tackle, but can be made from most anything, including just a length of line lead from the clew of your jib via an appropriate turning point to a winch.
- Slow down to a more moderate speed. Think of it as similar to slowing down your car when you come to a rough road.
- Choose a sail combination according to direction. Downwind, reduce the main area first, then the jib. Upwind, reduce jib area first, then the main. This is just a rule-of-thumb. It must be tailored to the individual vessel. If pressure on the helm is excessive and the boat wants to constantly break away, raising or lowering the dagger boards will allow you to fine tune the boat to near perfect balance.
- Expect to hand-steer downwind in big waves. Your auto pilot will not be able to react fast enough, nor can it anticipate waves. The trick is never to allow yourself to be perpendicular to the waves, but always to be at an angle to them, especially if you are sailing a keel catamaran. By taking the waves from the rear quarter you are always sailing downhill and you reduce the chance of pooping or pitch poling (pooping is unheard of in cruising catamarans and pitch poling comes from excessive speed perpendicular to the waves). If caught in a situation where an errant wave plunges the boat head-on into a very steep sea, the importance of full volume, properly designed bows will play a great role in safely stabilizing the boat and preventing disaster.
Getting to windward
If you seriously feel the need to maximize your heavy-weather windward ability under sail, then you must be prepared to change headsails for the purpose. Roller-reefing sails are good to a certain point. It must be remembered that a sail is sewn to pull against the head, the tack and the clew with the luff supported by a stay. When a sail is partially rolled, it is no longer pulling against the designed strong points, it is pulling against the luff and the foot where they roll around the stay. While it is possible to do reasonably well with a partially rolled jib, it is without doubt much better to have a sail specifically cut for that purpose, such as a good storm jib.
On the other hand, if you do what most cruisers do and simply run your engine about one third your normal cruising speed you will go to windward just fine. This motor-sailing concept is almost the universal choice of cruisers for going to windward in heavy weather. In a catamaran with twin engines, it is usually necessary to run only one of the engines, preferably the leeward engine, to gain the desired effect.
Knowing when to reef
This is the most often asked question concerning multihull safety. The answer is deceptively simple: “It is time to reef when you first think about it.” This is not meant to belittle the importance of knowing that “time”. As you acquire more experience with your particular boat, the more feel you will get for the process.
Let us compare learning how to “feel” your boat with how you learned to “feel” your car. When you first learned to drive, how did you know when to start slowing for a stop? If you started slowing too soon, you created a traffic hazard. If you started too late, you wound up with a panic stop or a rear-end collision. How did you learn this subjective judgmental skill? How did this judgmental process become habitual? The “feel” just developed with experience.
Subjective sailing. From the subjective point of view, when you begin to feel uneasy, apprehensive or concerned, it is time to reef. The correct time to reef will also depend on your state of mind, nature of the boat, the sea room and sea state. When the boat no longer has its feather light touch at the helm, it is time to reef. When the boat’s motion changes from its normal light, resilient feeling to one of petulant obedience, it is time to reef. When the lee bow seems to want to plunge and bury, it is time to reef.
Objective sailing. From the objective point of view, when the apparent wind speed goes over 18 knots, it is time to reef on most boats. When you are heeled 2 degrees more than normal, it is time to reef. When you are no longer strong enough to crank in the sails, it’s time to reef.
Reefing, as referred to in this section, includes both headsail and mainsail. As a rule for masthead boats going upwind, reef the jib first; downwind, reef the main first. It is hard to generalize about fractional rigs. Sailing under main alone is typically far more controllable and the main can be reefed as necessary. The fully battened mainsail has the most sail controls, is held on two sides by spars, and can be given optimum size and shape. Modern mainsail reefing systems have gotten more dependable, but the sailors choice is still the dependable slab reefing system, which, with all lines lead to the cockpit can be done in 30 seconds or less. It is still the most dependable, quickest and safest reefing system around. With the help of the full battened main and lazy jacks (which can also be used as a topping lift) the excess sail is gathered neatly on the boom. Roller furling booms or masts in my mind, have no place on a highly loaded multihull. They will work most of the time in the first year, but will eventually fail when you need them most.
There is no substitute for experience, so take your boat out in a controlled environment in strong winds with some capable crew. If you have a cruising catamaran, sail it as hard as you can and try to lift a hull. You probably won’t be able to do it, but you will learn a lot about how your cat feels when you begin to reach the realistic usable limits. Then never sail your boat that hard again if you can help it!
A trimaran is far easier to judge when overpressed than a catamaran. The extreme initial stability of the cat muddles both sensory and visual clues. A trimaran initially heels almost like a monohull, and you can visually see the lee float being depressed. Since there is more heel, there is more familiarity for those used to monohulls. As with any multihull, however, the wide beam of a trimaran allows you trimming angles not available to monohulls, thus you can have far more control and can keep your power up longer. A good multihull also requires less power to move at speed because it is lighter and does not have the hull speed limitation factor of a monohull.
—contributed by Victor Shane, Para-Anchors International
The multihull configuration has proved itself to be more seaworthy than even the most ardent of its proponents anticipated. The proverbial fly in the ointment has to do with what many people perceive as the multihull’s Achilles’ heel: capsize. The argument goes that ballasted monohulls are more likely to capsize, and they sink while multihulls don’t. On the other hand, a monohull’s ballast will right the boat if she is capsized (even though she may be dismasted or have sustained other damage), while in the unlikely event a multihull is capsized she will need outside assistance to right herself (a ship with a crane, for instance). If that outside assistance is not forthcoming, the multihull will remain upside down indefinitely and may have to be written off altogether.
The dynamics that lead to capsize are complicated. Entire books have been written on the subject. Although simply lying ahull (broadside to the waves) is a technique that has been employed successfully on many cruising catamarans, as a general rule boats are far less likely to capsize when they are properly aligned with the seaway (parallel to the direction in which the wind and the seas are running). Many experts feel that the ability to survive a severe storm, whether on a monohull or multihull, is closely related to alignment, and therefore boats should be forcefully brought into alignment by some sort of a drag device. There are two classes of drag devices: 1) Parachute Sea Anchors used off the bow, and 2) Drogues towed off the stern.
A sea anchor forcefully holds your boat’s bow(s) into the seaway. A drogue keeps your boat aligned with the seaway if you choose to run downwind with the storm. According to experts, a sea anchor and drogue are two items that enable a multihull to be respected as a fully seaworthy, sail-anywhere yacht.
Parachute sea anchors. All boats are designed to penetrate the waves with their bows. This is especially true of multihulls which, as a rule, have knife-like bows. A parachute sea anchor is used to keep those knife edges pointed into the waves offshore, where the water is too deep to use a regular anchor. It aligns the boat by “anchoring” it bow-on to the surface of the ocean. More importantly, it provides sufficient drag to pull those knife-like bows through large breaking waves without allowing the capsize or pitch pole cycle to begin.
Small cone-type sea anchors have proven to be ineffective and unstable; what are needed are parachute-type devices. As a general rule, the diameter of the parachute sea anchor should be large enough (A) to maintain stable inflation without being tumbled by surface action, (B) to overcome the lateral resistance of any keels involved, (C) to hold the bow(s) into the seas and keep side-to-side yaw to a minimum, and (D) to reduce drift so as to protect the rudder and its fitting. As a general guideline the diameter of the parachute sea anchor should be at least 35% of the LOA for both monohull and multihull yachts. When in doubt select a bigger chute.
Modern parachute sea anchors must be used in conjunction with a long nylon rode to allow the boat to yield to the seas and not stand up against them. The long nylon rode is integral to the parachute anchoring system to prevent excessive dynamic loads. For both monohulls and multihulls it is suggested that this rode be equal to at least ten times LOA of the boat when in survival conditions (for example, a 40 ft. multihull will need a nylon tether that is at least 400 feet long).
Rode diameters should be the same as ground tackle rode. A bridle is essential for multihulls. It is recommended that the arms of this bridle be equal to 2.5 times the beam of the multihull (for example, a multihull with a 20 foot beam will have a bridle whose arms are about 50 feet each. A swivel is required at the parachute terminal and it is recommended that all other unions be in the form of spliced thimbles (no knots) utilizing shackles of equal strength which are wired shut.
Centerboards and dagger boards should be lowered (or partially lowered) when using a parachute sea anchor off the bow. This has the effect of keeping the CLR (center of lateral resistance) well forward which, in turn, minimizes the extent of side-to-side yaw.
Bow rollers used for conventional anchors can be used for the para-anchor; however these must have retaining pins to keep the rode in place (otherwise the rode will jump off the roller when the bow of the vessel dips down into a trough). Heavy-duty chafing gear must be used where the anchor line meets the boat. Never underestimate what chafe can do to your equipment, to your boat and to the lives of those on board. Chafe is the bane of any storm anchoring system. Never take it for granted that the protective rubber or leather sleeve is going to stay put; it’s going to migrate, and sooner than you think. Post anchor watch and keep a sharp eye on the gear.
The safest method of deploying a parachute sea anchor in heavy weather is known as the standing set. This method allows the boat’s drift to pay out the rode. The procedure is as follows:
- Head up into the wind, allow sails to luff and the boat to stall.
- Lower/furl all sail.
- Secure the rudder amidships, lower all boards.
- Heave the float.
- Slam-dunk the para-anchor ON THE WINDWARD SIDE (and never on the lee side, where the boat may drift over and foul with it).
- As the boat drifts away from the sea anchor, snub the line to help the canopy open under water (only half a turn is required on the cleat; do not fully cleat until adequate “scope” has been payed out.)
- Secure the rode; put on chafe gear.
An alternative method, commonly used by commercial fishermen and requiring a great deal of practice, is known as the flying set. In this case the vessel is placed on a downwind course and the para-anchor is jettisoned off the stern while quartering the seas on storm jib or bare poles (mainsail has to be furled). With all but the last coils of the line slipped, the helm is put down hard. As the slack goes out of the system the rode will pull the bow around into the wind. A WORD OF CAUTION: Because of the dynamic and/or shock loads involved in attempting to stop a heavy boat that is moving downwind at some speed, the author does not recommend the flying set in heavy weather situations.
Parachute sea anchors can be retrieved by means of a full or partial trip-line. I favor attaching the trip-line to the crown of the parachute, since it enables the crew to invert the canopy and retrieve it with relative ease. A partial trip-line doesn’t come all the way back to the boat (unlike the full trip-line) and hence reduces chance of nasty foul-ups. The procedure is fairly straightforward; simply winch (or power) the boat up to the second float and retrieve it with a boat-hook. Haul in the trip-line and bring the chute on deck. Even so, it is best to wait for calmer weather before retrieving a large parachute sea anchor.
Drogues. Drogues generate much less drag than parachute sea anchors and require considerable sea room for use. They are towed off the stern in order to limit the speed of the vessel when running before strong following seas. Speed-limiting drogues are, for all intents and purposes, steering assist devices, requiring a man at the helm. They may simply consist of a warp (length of line), or warps, with bights of chain attached. They may consist of any number of on-board items towed off the stern, or they may be purpose-made devices.
Drogues must track straight as they are being towed through the sea. If the drogue configuration is unstable it may “squid”, “kite” and “zig-zag” in a seaway, allowing the tow-line to go slack and boat to possibly broach and capsize. Stable tracking is critical in association with the drogue concept. Whereas large diameter parachute sea anchors are designed to block the flow of water outright, small drogues must be designed to allow for very stable flow configurations. They may be solid plastic devices shaped like torpedoes, as is the case with the two-stage Australian Sea Brake, or they may be parabolic baskets fabricated from strong nylon webbing, as is the case with the American Galerider. Other devices may work, including those associated with defense and aerospace recovery systems (ballute, guide-surface, hemisflow, ringslot and ribbon chutes used mainly for aircraft deceleration).
Speed-limiting drogues are used in conjunction with several hundred feet of nylon or Dacron towline (consult the manufacturer’s instructions). In general, it is necessary to use some chain next to the drogue. This helps to keep the drogue submerged. Any speed-limiting device may lose its bite if it is allowed to surface, cavitate and/or be pulled out of a wave face. In this connection it is important to position the drogue behind its wave when the boat is beginning to surge down the face of another wave. This pulls the drogue through the meaty part of the wave (and not into thin air).
Drogues used with bridles will take more control of the whole situation. Even so, they are not designed to take total control of the situation, as sea anchors are. If the boat needs to be steered, on the other hand, no bridle should be used. By bringing a single towline to a winch well forward of the rudder the helmsman may be able to steer the boat freely, even with the drogue in tow. Raising and lowering the boards will give additional control, either to the drogue or to the helmsman.
Drogue or sea anchor? Speed-limiting drogues are designed for low drag. The associated “Catch 22” is as follows: the same low drag that allows the boat to be steered may allow the boat to be pitchpoled in the ultimate storm. The forces that pitch pole a boat are so great that they will yank the drogue through the sea while throwing the boat end over end. You need the higher drag of a sea anchor to be physically pulled through the breaking sea (and not be thrown by it). It goes without saying, therefore, that the prudent sailor will have both items on board, and know when to use which. If he is towing a speed-limiting drogue off the stern, for instance, the prudent sailor will keep an eye on the barometer in anticipation of making the transition from drogue to sea anchor. And if that transition becomes imminent the prudent sailor will go to the sea anchor early on in the game, long before he is irrevocably committed to the dread toboggan ride to oblivion.
You will be able to remain under sail in many heavy weather situations on a cruising multihull—as long as you reef when you should. You will probably find when the wind is up you can go just as fast reefed down. Besides, most times you will want to slow down a bit to remain comfortable—yes, a bit like slowing your car down when you come to a rough stretch of road. There is one other basic rule of thumb associated with reefing: on a monohull you typically reef to the strength of the gusts, while on a multihull you reef to the strength of the lulls.
by Gregor Tarjan