– Cat Not Dog part II –

In the second of a two-part enquiry, Alex Stone continues with the main considerations to be taken into account when buying a modern cruising multihull.

DISPLACEMENT AND PAYLOAD

The acres of space that bridgedeck cruising cats offer has tempted many owners to pile on weight everywhere. An example of this is a friend’s boat (she’s sold it now) that was the same length and accommodation as our 12m cat, but was literally twice the weight. There were Teak extras everywhere, Teak deck veneer, oversize motors, you name it – all too easy to install. And all having an effect on that boat’s performance. But still, it was (and remains so) a fine cruising boat – just not quite so fast. It’s the boat pictured above - a 30-year-old Grainger design Mind you, we got it up to 18kts with the kite up, and under autopilot …

A note on the consequences of your choices here. If you have opted for the long-lean-fast hulls, you won’t have much margin for generosity of payload. (See Hull Shape, coming up …)

You may need to ask guests to limit their luggage weight – but, hey, if airlines can do it, why can’t we?

Cat does Dog. Image Lesley Stone

GALLEY UP / GALLEY DOWN?

This debate appears almost to be resolved among experienced cruising cat sailors in favour of the galley-up option – ie in the bridgedeck saloon, not down in one of the hulls.

Which does leave an inordinate number of boats in the secondhand market with the galley-down configuration. The best advice on this is to make up your mind for yourself: go cruising overnight(s) with both options. Yes, some people do prefer galley down, for their own reasons – it may be that they feel more secure, less-seasicky down there (if the galley is well-ventilated); it may be that you prefer food preparation away from the sitting/lounging space. Your choice. Galley up or down also affects the placement of your fridge/freezer.

On our boat, we’re totally sold on the galley-up configuration, with windows above the kitchen bench leading directly to the cockpit. This makes for easy al-fresco serving and eating, and great ventilation for the galley stove too. And this was after initially favouring galley-down – so we are converts.

This shows the relatively beamy hulls of this French design. Also the solar panels and windmill for additional energy generation; and the accessible liferaft stowage.

GROUND TACKLE

Armchair Admirals may regale you with horror stories of cats and tris misbehaving at anchor, and sailing alarmingly around the anchor point. This is exaggerated. But it does pay to have a good, and easy-to-attach bridle system that leads from the outside bows to the central anchor chain or rode. This minimises the swinging at anchor.

Also, anchors that are deployed directly from underneath a cat’s bridgedeck, rather than from a point below the front crossbeam, come with attendant hassles. In real racing multis, naturally the anchor is kept away from the bow, but this is not really a concern with cruising cats. Generally, cats and tris have lighter anchors too.

Yes, light multis can move about at anchor, especially those with wing-section and/or rotating masts. This can be minimised by cleating the mast off to one side; or if you have two masts (a ketch or a biplane rig) by setting the masts in opposition to each other.

One advantage offered by all multihulls is the ability to anchor in shallower water than the keelboats.

HALYARD LEADS

Some cruising cats have the halyards leading from the mast base, down under the bridgedeck, to a central winch placed behind the cabin. This system usually has too much friction from the additional three turning blocks; and offers poor visibility to what you’re doing. Not recommended. One way to get around this visibility problem, is to lead your halyard tail around the central winch, and to a side genoa sheet winch – if there’s a fair lead to do this. But you’re also then adding to the resistance. We shifted our mainsail halyard and topping lift to side-deck winches – and left the lesser-used halyards in the awkward position. This works for us.

By the way, a 2:1 mainsail halyard is common on multihulls – this to make up for the added inward pressure from the full-length battens in high roach or square-top mainsails.

HULL SHAPE

Hull beam:length ratio, and displacement:length ratio

Look along the length of any cruising cat from dinghy-eye level. For many, the hulls will appear rather chunky, with volume distortions on the inside, leading up to the bridgedeck (this is to allow interior space for bunks and stairwells). If this distortion is well above the waterline, that’s okay.

For any kind of performance, your cat will need hulls of a (waterline) beam:length ratio of at least 1:12. Or a minimum of 1:10. The commodious types of cruising cats will often be very different to that – some down to 1:6. Buyer beware. Similarly, a trimaran with an almost monohull-like central hull will not be very fast either.

The ratio of hull length to displacement is also important. Australian Tony Grainger explains on his very fine website: “The longer the hulls for a given mass (displacement); the lower the displacement to length ratio, the more easily driven the hulls are and the more sea kindly the motion of the vessel in a seaway.”

Reverse bows? They look like the new fashion. But they’re not just a fad.

Tony Grainger again: “... for displacement hulls reverse bows are the state of the art in our technological quiver where performance is paramount. They can be beautiful and those that are will endure just as many of the classic sailing yachts of the past have endured for their beauty. 

“The important thing is not whether the bow points forward or aft, the important thing is whether all of the design features work cohesively in style and in function.” 

A new trend in fast cats are fuller hulls in the forward sections. The may look strange to traditionalists, but if the boast is from a reputable designer, trust him/her.

The hulls on this cruising cat are narrow below, and wider above the waterline, making for a more spacious interior. Image Lesley Stone

MAST STEP

A number of modern multihull designers take great care to place the mast step on a flat section of the deck, or on a horizontal step in the coachroof as it slopes down.

This is for ease of working at halyards around the mast base; and a good thing for safety at sea. A mast step on the top of the coachroof is both unsafe and usually structurally less sound.

MINI-KEELS OR DAGGERBOARDS?

An enduring debate amongst cruising cat sailors and designers; and one with the jury still out on the benefits-vs-compromises balance. Most of the ‘production comfortable cruising cats’ will be marketed with mini-keels. The advantages of this arrangement they will say, lie in the fact that this allows the boat to be beachable, reduces draft, protects the saildrive and rudder, offers internal diesel or water storage, minimises complications (no hassles with raising or lowering daggerboards), cleans up interior layout (no daggerboard cases running up through the hulls) – and anyway, there’s no significant performance downside.

But there is one, and where it counts most for safety – in storm conditions. Fixed mini-keels won’t allow a boat to slip sideways under duress, and this can provide complications aplenty when wind and waves are high and threatening. After surviving a full-on oceanic storm in our light daggerboard cat (see Australian Multihull World November 2020) we found that the retracted board could now be flush with the hull – thereby allowing the boat to slip sideways safely.

But Grainger notes “I’ve never heard of a cat tripping sideways over its keels but please enlighten me if this has been the case.” Here he’s talking about capsizing.

Daggerboards will give the boat better all-round performance, on all courses relative to the wind. Going upwind, you’ll have deeper, higher-aspect and more efficient underwater foils; you’ll go faster and point higher. On a reach, especially in a smaller cat, you’ll have the option of raising the leeward daggerboard – which will allow the boat to safely slip sideways if the windward hull lifts out of the water. Downwind, you can reduce drag by lifting both daggerboards.

Grainger writes: “I generally recommend that daggerboards are a worthwhile investment if the owner has a preference for sailing to windward rather than motoring or waiting for a favourable breeze, and if the boat is going to be kept light enough to have a power to weight ratio that will do justice to the dagger board configuration. 

“As a rough guide I would suggest that a 40’ cat which had a sailing weight of six tonnes or less would benefit from daggerboards, while a relatively heavy cruising cat would gain very little  benefit from the more efficient foils.”

And that’s the important point here: is your aim primarily to have a performance sailing craft? Or a more commodious vessel, that you’re happy to motor-sail more often?

LAYOUT AND ACCOMMODATION

Space, lots of space, say the pictures in the ads for the modern cruising cat. Especially those from European production-line facilities, with big marketing budgets behind them. Great lighting, and wide-angle lenses all add to the impression. And plans of the layouts will show double berths in en-suite cabins aplenty.

Here’s where a reality check is needed.

The width of a bridgedeck cats can also be their downfall. Some of the ‘commodious’ types of cats have been stacked so full of bunks to look almost like dormitories. Trimarans, of course mostly have their accommodation concentrated in the main hull, with bunk spaces leading out over the deck, but never into the amas (the outriggers).

On our boat, a light Schionning-design 12m cat, the bunks are all within the bridgedeck volume, and the bows and sterns are pretty lighweight. The single bunks are pretty wide, and could easily ‘top and tail’ two kids. The engines are lifting outboards in the boxes beside the twin steering wheels. In many of the ‘commodious’ cruising cats, you’ll see an extra double cabin in this space, thereby being able to boast about extra accommodation for four more people. But ask yourself – do you really want 10 people on a 40ft boat? Mostly we go cruising with another couple, and we each have our own hull and heads.

If the design you’re looking at has accommodation that stretches fore-and-aft to a greater degree than this, it will certainly come with performance compromises.

Another thing to look out for is where the dinghy will be hanging. Ours is suspended from the targa – and it’s lightweight, being an inflatable and not a hard-bottom type. If your cat has the dinghy hanging right at the aft end of the boat, it will probably contribute to the sterns dragging.

Which leads us directly on to …

Two wheels on this Schionning cat. Each has good visibility, and allows the helsmperson some shelter behind the cabin top.

PERFORMANCE

Much of the current mythology of cats and tris is based on their touted superior speed. But it ain’t necessarily so. Modern, composite-hulled, moveable ballast keelboats are very quick indeed, and can have a speed advantage over multihulls – especially the commodious cruising types – in light airs upwind or dead downwind.

To gain the performance advantage, your cat or tri will have to be of lean hulls, lightweight, with deep daggerboards and an efficient rig. But this combination is possible – and commonly so.

There’s a whole new chapter (books, even – but mostly experiential learning) on the different aspects of seamanship and sailing fast multihulls. That’s the subject of future article(s).

SAIL WARDROBE

Unlike many monohulls, you can get away with a surprisingly limited wardrobe of sails on an efficient multihull. We cruise happily, and fastly, with a blade jib (self-tacking, and on a forestay furler), a Code Zero (also with a luff furler, so it can mostly stay up overnight at anchor), and the usual fully-battened main with deep reefs. We can go on the wind, faster than the wind, in light airs with the Code Zero. Once above 10kts, we’re fine with the blade jib. A genoa is not necessary for cruising, with this set-up.

SHOCK-LOADING

The heeling motion of a monohull is a shock-absorbing effect. Cats do not have this luxury. Gusts of wind are imparted more as shock loads to the rig. So you’ll notice a catamaran will have seemingly over-sized rigging and attachments. This is normal. In fact, if the rigging seems just like on a comparable length monohull, that’s a red flag.

Another collateral to this is that going up the mast at sea on a cat is decidedly more uncomfortable than on a monohull, which has its motion smoothed/regulated by the dynamic forces of heeling. At the masthead of a cat, you’ll be whipped around in a much sharper motion, and in four directions. Be prepared.

Galley-up always provides the cook with a view – and a handy serving hatch to the cockpit area.

STEERING: TYPE AND POSITION

Most cruising cats on the secondhand market will have wheels, and most will have only one. In a wide boat, this can be tricky, especially in a docking situation.

So consider: if there’s a central steering position, is it really practical? Some are placed up high, with a view over the coachroof, but this comes with added windage (for the boat), more wind in the face (for the helmsperson), and a safety concern about falling down the ladder. Boats designed for blue-water sailing will never have this feature. And yes, there are central steering positions on some cats that offer very limited visibility forward.

If there are two wheels, do they both have engine controls leading to them? If not, will you be comfortable doing close manoeuvring always from one side? (With someone on the other hull calling distances etc)

If the boat offers tiller steering, is it comfortable enough to use? Or does it mean the poor helmsperson will always be exposed to the wind and the spray? And for both tiller and wheel steering, are there options for steering standing up and sitting down?

And lastly, a significant safety/emergency consideration: does the boat have a ready, easy option (and emergency tiller, for example, that can be attached to the rudder post; or a spinnaker pole or suchlike, that can be re-deployed as a steering oar?)

WEIGHT DISTRIBUTION

Look for added weight up-front in a secondhand cat. Often, owners have been tempted to fill the commodious for’ard storage hatches, or under them, with extra water- or holding tanks. This is not a good thing.

Buying a cruising yacht is a major investment for most of us. These are just a few pointers to getting your choice just right when you are looking at switching to a multihull, or upgrading to a bigger one. Choose wisely, and you will be well rewarded.