What Are The Catamarain Bulkhead Spacing

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Usually the very first comments boat show visitors make when stepping aboard a large cruising catamaran is related to the vast amount of room as compared to an equivalent length monohull. Close to ideal cockpit shelters, large amounts of storage, and 360-degree saloon views are just some of the space and layout advantages of multihulls.

Thanks to the wide beam of a multihull its volume is much more than meets the eye. We all know that for every additional foot in length, the interior of a monohull rapidly increases. This phenomenon is taken to the extreme on a catamaran where even several inches additional boat length will provide more of everything than ever dreamed of. This is most noticeable when experiencing the vast space of a catamaran's main deck.

The saloon and cockpit account for the major portion of a catamaran's bridge deck and usually span from the aft end of the cockpit to the central, mast-bearing crossbeam. Not only is this area the most comfortable part of the boat, since it is close to the center of gravity (CG), but it is also where most of the action takes place. In fact, more hours are spent in the cockpit or the saloon of a catamaran than in bed. In contrast to the typical monohull, where the cockpit is separated by a steep companionway ladder leading down into the cavity of the boat, a cruising catamaran provides a close to ideal surrounding.

Froude's pendulum experiment proved that no matter how inclined the wave-face angle, the pendulum remained perpendicular to the sea due to the effects of momentum.

Froude's Pendulum

The cockpit, even on a 45' catamaran, has enough space to separate the helmsman from lounging crewmembers. Often the sheltered corner just aft and to one side of the saloon bulkhead is utilized for a fixed cockpit table. We often have 10 people on our boat without feeling cramped. There is sufficient elbow room for winches to be operated and usually the mainsheet traveler is either on the bimini arch or aft of the cockpit settee, well separated from passengers. On a monohull one sits "within" the cockpit, as one would in a bathtub. The helmsman will often have to squeeze by the huge wheel, and the sitting and lounging area is less than one third of that of a cruising catamaran. The bitter ends of halyards and lines quickly clutter the largest cockpit and make them look messy. On a monohull it is often unavoidable to be sitting or standing on a rope, which is not necessarily comfortable nor safe. The greater deck space of the catamaran also allows designers to route sail controls in such a way that they are not only strategically placed for efficient operation, but also out of harm's way of the passengers. This is one luxury that monohulls do not have either.

The bimini is an essential item on a cruising boat and in my mind is often underrated in its design. Few boats - monohulls and multihulls included - have smartly integrated or good looking biminis. Often one sees a beautiful looking yacht with sleek hull lines only to discover a ridiculous looking contraption of above For half the price of a top waterfront condo, you could visit the most beautiful harbors and anchorages aboard your private island. Here the cockpit feels like an extension of the saloon; even the sliding moon-roof permits unobstructed view of the stars.

below Yapluka 70 saloon complete with wet bar and lounge area. Classic elegance and top workmanship at its best.

steel and canvas perched over its cockpit. Usually biminis on monohulls are more of an eyesore, as they are completely freestanding and do not benefit from the protective structure of the coach house as found on a catamaran. The only solution for the monohull is a small dodger, which protects the open companionway from spray and barely provides shade. In contrast, bimini structures on cruising catamarans are not only esthetically more pleasing as they can be tied into the deckhouse, but they actually do what they are designed to do.

The giant sliding saloon doors of a multihull invite the crew to enter the bright saloon from the cockpit, which is often on the same level. There are no steep ladders or steps to crawl over. Similar to an expansive patio, the living area created by the bridgedeck saloon and cockpit rival those of small penthouses.

They truly are one of the best parts of a catamaran. One can entertain, cook, navigate or simply lounge with enough room not to be in the way of another crewmember. On long ocean passages, this is refreshing indeed. Some catamarans have the galley facing aft against the saloon bulkhead and feature a configuration resembling a bar. This permits the chef to easily pass drinks or food to guests in the cockpit. Try balancing beverages and plates up the steep companionway of a heeling monohull.

The 360-degree view from the saloon allows unobstructed sight forward and aft. In most cases the settee is placed against the forward side of the bridgedeck in order to create a transverse passageway for the hulls. The seating arrangement is usually slightly elevated to provide an outside view without having to strain neck muscles. In inclement

weather, seeing outside from the protection of the saloon is especially reassuring to novice sailors. On a typical 45' catamaran the dinette can seat 6-8 people for elaborate dinners without hindering the access and circulation in the saloon.

The galley is usually not far from the dinette. On most cruising cats the chef is where the guests are and is part of the social action. The cook is happy on a multihull, with plenty of storage space, ventilation and natural light. The front opening refrigerator does not necessitate acrobatics to get to the bottom of it and communication with the crew in the cockpit does not require shouting or hand signals. In short, even the galley on a small multihull is any chef's delight.

Visibility Ergonomics
Antares Pdq Catamarans

above One of the most overlooked features of good cruising boats is the forward-looking chart table, which lets you navigate and even steer the boat via push button controls in inclement weather.

Whereas on a monohull, passengers live within the confines of the interior and often need to strain to catch a glimpse of the horizon, catamaran sailors reside above the waterline and enjoy unsurpassed 360 degree views, whether standing or sitting.

far right Wide, unobstructed teak decks are not only elegant, but also safe to walk on; however, they will require some maintenance to keep them looking good.

below A gourmet's delight and a chef's playground; the finely fitted galley. Although most galleys are found on a catamaran's main deck, they can also be placed in the hulls.

Storage space is usually (too) abundant on a catamaran. Where "deep-storage" items disappear into a monohull's bilges, the same goods are kept in house-hold type shelves and lockers. It is often frightening how many closets are found on a multihull. Sadly, sailors tend to stuff them full of items which are never needed. Everyone falls into this trap. I have often discovered items on our own boat, which rotted in the bottom of a dark bin, that I never even knew existed. It should be noted that one of the drawbacks of light multihulls is the erosion in performance when loaded. Therefore care should be taken to keep the payload within the designer's parameters.

Have you ever tried hand-steering a monohull from the inside navigation station? One is literally blind as there is no way to see forward. Usually inside helm stations are an afterthought on a monohull and it is rare that one finds a pilothouse boat with a proper forward facing navigation station. The majority of today's cruising catamarans have inside helm stations, which feature duplicate instrumentation and

Generous room, more possibilities for a smart layout and the non-heel environment of a cat will allow sailors to perform boat handling tasks much easier than on a monohull. Beginners will gain confidence joystick helm controls. The operator has 360-degree view, can navigate, make course corrections and even tack (with a self tacking jib) while sipping a drink and comfortably seated. Abundant space and the unique layout of the multihull's bridge deck permit this invaluable feature. Anyone who has hand-steered a boat in torrential rain can appreciate the importance of an inside steering station.

The charter industry realized the practical nature of spacious money-making catamarans, which can often accommodate 4 paying parties or more. Well separated in the four corners of the boat, 2 couples sleep in each hull and guests sometimes do not even realize that they are not alone. The privacy provided by the hulls is unique and one could sleep undisturbed while another couple is watching a movie in the main saloon on the bridge deck.

Owner's layout multihulls feature an entire hull dedicated to the proprietor. Even on a typical 40' catamaran, a double berth aft is separated from a desk and lounge by closet space, while forward one can find en suite heads with separate walk-in showers. A cruising catamaran's abundant space and accommodation plan will provide a higher standard of living. Because of this the crew will find itself in a safer surrounding and a more ergonomically optimized environment than on any other vessel.

Boat Handling

Generous room, more possibilities for a smart layout and the non-heel environment of a cat will allow sailors to perform boat handling tasks much easier than on a monohull. Beginners will gain confidence

quicker, and a catamaran's redundant engine and steering systems will permit not only better maneuverability but also more efficient motor-sailing and the ability to beach the boat. Let's look at these characteristics in detail.

below This is not the cockpit, but the flybridge of a large cat! A second helm station forward allows unrivaled views of the horizon and a sun pad provides lounging space for sunbathers; a stairway leads to the main deck below.

Many novice sailors are always astonished by the fact that I know people whose first boat is an 18-ton, oceangoing sail-catamaran. This should not mean that everyone can take a multihull around the world without experience, yet basic maneuvers are easier learned on a stable and more user-friendly catamaran. This greatly boosts operator confidence and because of that the learning curve is often steeper. The twin engines and high helm position of a cruising catamaran greatly facilitate docking and tight harbor maneuvers. A monohull's single screw will make a novice guess which direction the prop will "walk" and often bowthrusters are the only answer to back a big monohull into a tight slip. In contrast it will only take several times for beginners to understand the simple principles of the turning power of widely spaced twin diesels and soon maneuvers that seemed impossible are mastered with confidence.

Froude Pendulum

It is not uncommon to see women driving a multihull into a tight berth, while the husband prepares lines and fenders. The galley is certainly not the only place where our female companions feel at home and their reign has extended to the helm and beyond. It is a refreshing fact that I notice more women at the helm of a catamaran than on a monohull.

Have you ever seen a novice sailor clutching to the rail of a heeling monohull in a fresh breeze, eyes bulging, mouth dry and with an expression of apprehension? These will be involuntary reactions to a heeling and pitching environment, which is completely alien to dry land. Imagine the entire crew in foul-weather gear, huddled together and sitting in a cramped cockpit with water rushing by only inches away. Even worse, the novice is promoted to act as "rail meat" and is ordered to do something as useless as sitting on the windward deck. Now the wind increases and the captain orders the mainsail to be reefed. The boat turns into the wind, the mainsail flaps violently and the skipper shouts commands over the howling wind. The novice sailor starts wishing he were somewhere else as the monohull labors head into the seas, and waves crash against the bows causing spray to fly back into the cockpit. As crewmembers stagger forward to the mast and finally reef the mainsail, the boat is lurching to each wave, the boom is whipping dangerously from side to side and the noise and chaos is frightening. Our apprentice is ready to go back home, thinking that only experienced and tough seamen are made to sail the ocean. He feels that he is definitely not one of them. Of course, this example might be a bit exaggerated, but is often not far from the truth.

Reefing a boat, even on a multihull, can be a drama-filled event, where usually pulses quicken and crewmembers' alertness increases.

On a catamaran the novice would not feel that he is half submerged by sitting in a cockpit. Psychologically he would feel safer too, being high and dry on deck, many feet away from the water. Or the newcomer could be sheltered in the coachouse saloon and still be part of the action by observing the events from the safety of the settee. Even in the large cockpit he would be out of the way and not feel like a useless burden.

The beauty of a well-designed cruising catamaran is that one does not have to round up against the wind to reef the mainsail. This will reduce the excitement of the action and avoid the boat having to stomp into head seas, greatly eliminating the anxiety factor. Today's fully-battened mainsails and lazy jack systems allow a multihull to be reefed, even when sailing downwind. Apparent wind is reduced and the reefing maneuver is less taxing on boat and crew.

From running new sheets for the gennaker to performing a simple repair, actions are usually easier on a multihull with its wide and stable platform. For instance there is no need to tiptoe to a pointy bow to set and check the anchor. A multihull usually has the anchor resting on the front or central crossbeam with enough room to spare to attend to it. Making emergency repairs on a wide forward trampoline in the middle of the ocean (I have done my part) is so much easier than on a rolling stage as on a monohull. Even searching for an important item stored on above Your private owner's suite, nearly 35' long; complete with dresser, lounge and a walk around - queen-size double berth, as found on the very successful Bahia 46 cruiser.

next page Pulling into a new harbor, the wide side decks are the best vantage point to take in the new surroundings and scout out anchorage locations.

Multihull Advantages and Drawbacks

Multihull Advantages

Multihull Drawbacks

Unsinkable - foam construction and more bulkheads

Usually more expensive, length for length

Non-heeling environment

Will stay inverted when flipped

Higher average speeds

Bridge decks can slam if not high enough

More interior space, 360-degree view, optimized layout

Not as easy to find dock space

Shallow draft - safer and more access to harbors

Performance decreases more rapidly when overloaded

Twin-engine and twin-rudder redundancy

Windage can be high

Safer sail-handling and reefing procedure

Quicker motion, especially sailing upwind

Better interior steering station - often forward facing

Not fleet-friendly racers

Better protection in cockpit against sun and rain

More maintenance

Better autopilot function

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How To Have A Perfect Boating Experience

How To Have A Perfect Boating Experience

Lets start by identifying what exactly certain boats are. Sometimes the terminology can get lost on beginners, so well look at some of the most common boats and what theyre called. These boats are exactly what the name implies. They are meant to be used for fishing. Most fishing boats are powered by outboard motors, and many also have a trolling motor mounted on the bow. Bass boats can be made of aluminium or fibreglass.

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Responses

  • Haben
    What are the catamarain bulkhead spacing?
    2 years ago
  • kimi
    What size are catamaran bulk heads?
    8 months ago

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