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Eco 5 Power Cat

A catamaran for cozy cruising

From Issue   March 2016

W as it time for another boat? In the 1980s, it was a 16′ sailing dinghy that awakened my wife Barbara and me to the beach-cruising pleasures of the San Juan Islands in Washington’s Puget Sound. In the ’90s, it was a 19′ lug-rigged double-ender for oar, sail, and outboard that extended cruising to Desolation Sound. Then came a 20′ catamaran, sporting a wing mast with square-topped mainsail, that got us inside a comfortable cabin while offering exciting sailing in moderate conditions. But as years went by, sitting out in the weather and hauling sheets took its toll. Sailing was exciting when the wind was up, but boring in light summer winds. Why bother with sailing if we could motor at 10 knots? Was it time for a gasser?

And so it was, and we decided upon the Eco 5 Power Cat by Bernd Kohler in France. Its narrow hulls, wave-piercing bows, space-age profile, and three-tone color scheme really made it a looker. At 5.5 meters, it was about the same size and accommodation as our 6-meter sailing cat, and still trailerable behind our compact SUV. The twin 5-hp outboards specified in the plans were to drive the EcoCat at an economical 10 knots and spin it around in circles. Having them mounted on the transoms should eliminate weed pickup, as well as the between-hull wave buildup working against a centrally mounted outboard. I ordered plans, and the digital files came quickly via email.

The plywood-on-frame EcoCat is simply built, using chines sprung around widely spaced bulkheads. I opened the DXF files on an older Mac Cube still running Drawing Board CAD from Ashlar Vellum. With CAD, I made some design changes for a bit more cabin headroom, bigger windows, storage lockers forward, and extended cockpit sides complementing the cabin profile.

The Eco Cat rests comfortably on the cobbles between tides. There’s room aboard for an inflatable kayak when a dinghy is required if the Cat’s at anchor.

Once I had the design tuned to suit our needs, I nested parts for economical use of plywood sheets, created a tool path for the ShopBot CNC router I’d used for our rowing-shell kit business, and quickly cut out the parts from 6mm plywood. It sounds complicated, but it’s actually similar to laying out parts by hand—but with parts cut far more accurately, with beautiful, fair, and smooth curves everywhere. I milled clear Sitka spruce to dimension, scarfed it to full lengths, rounded edges, and precoated everything with epoxy. This self-made “kit” made for very fast building.

The building jig had only one temporary form; all other forms were bulkheads that remained with the hulls. The hulls were built upside down, planked, and even finish-coated with graphite-infused epoxy—later I’d paint above the waterline. The 6mm planking was patterned on the hull, as the actual faired shape may be a bit different from a CAD plate expansion, then glued in place and trimmed. The hull and side-panel sections were joined with butt blocks that added stiffness in way of the temporary bulkhead. After I flipped the hulls upright and aligned them, I fit the deck—scarfed 12mm plywood. The cabin sides and top were built up with two layers of 4mm ply. It took just four months for me to complete the construction of the hulls and cabin.

The partially finished boat looked great, and I decided to spend the big money for a two-part paint sprayed on by a professional, thinking it would be done quickly. Wrong. It was another six weeks before the boat was back for outfitting. The plans showed a windscreen here, a galley there, a steering wheel, and twin outboards—but no details. It was just another challenge to work through.

The two small outboards were a good fit for the twin hulls, but didn’t provide adequate power.

Remote steering and motor controls for twin outboards is very routine for a monohull, but not for tiny twin 5-hp outboards on a catamaran! Time to improvise. A tiller bar, supported on nylon bushings, was hidden in the cross beam with a mechanical steering cable connected to the dash-mounted steering wheel. What a challenge it was just to have twin motors on a little catamaran.

Another professional I hired designed an excellent canvas dodger, back panel, and semi-rigid windscreen that really complemented the design. Barbara and I could now cruise, completely protected from wind and rain, sitting in comfortable captain’s chairs. The 6′ x 8′ cockpit is our living room at anchor, doubling the EcoCat’s enclosed space. A Yeti cooler, good for five days, stays in the cockpit as a table or extra seat. An Origo two-burner alcohol stove eliminated complicated propane systems. We use a lightweight 32-amp-hour starting battery, not for the pull-cord-start outboards, but for powering LED lighting and an iPad for music and charts with the Navionics app. We only need the instruments powered up while we’re under way, so the outboards’ 6-amp charging outlets supply power directly to the instruments and charge the battery at the same time. No shore power is needed. Simple systems for a simple boat—its name, JUST ENUF, serves the cat well!

The Cat’s shallow draft and twin hulls open up options for anchoring in shallow coves. If the bottom is even and not too rocky, grounding out during a midnight low tide isn’t a problem.

D uring the boat’s first season we took a two-week cruise to British Columbia’s Broughton Islands. The cruise covered hundreds of miles, and we alternated between being the only boat in a secluded cove and being surrounded by the warm hospitality of wilderness float marinas. A comfortable 80-mile range and top speed of 10 knots allowed us to do plenty of exploring without concern for time or fuel. The EcoCat is comfortable in sea conditions of 2′ short, steep chop and can confidently deal with far rougher conditions.

Having the lines of the Eco Cat in CAD files simplifies making alterations like raising the cabin roof to provide standing headroom.

This 8′-wide catamaran offers the stability and seakeeping of a far larger boat. There’s never a problem grabbing for a hot pan when another boat, zipping by to look at JUST ENUF, leaves its wake for us. There is plenty of room with a hanging locker and two cuddies for each person. Sleeping bags with integrated mattresses make a very comfortable double. When bags are folded over during the day, the large padded bridge deck area is very comfortable for sitting, cooking, and just hanging out. The starboard hull has a cushioned canoe seat atop the porta-potti. Just forward is hull storage for an inflatable kayak or two folding bikes and other bulky gear. The port hull has standing headroom at the sink and sit-down room for meal preparation with a flip-down table for dining.

A single 20-hp outboard can outperform twin 5-hp outboards. Just behind the motor’s shaft you can see one of the extensions added to the hulls to improve the trim with the greater motor weight. The custom-made canopy doubles the Cat’s sheltered space.

The twin 5-hp outboards proved to be not enough power. They had no top-speed potential, pull-cord starting, and were noisy, especially with the steering linkage rattling between them. Worse, the tiny props had so little bite that docking maneuvers were a constant challenge. A repower with a single Yamaha 20-hp outboard yielded a 10-knot cruising speed, 15-knot top speed, and the same fuel economy as the twin 5s: 1 gallon per hour at any speed. Electric start, 6-amp charging capability, and a lightweight battery competed the package. A 1′ extension added to the stern of each hull helped offset the additional weight of the larger motor and its under-deck 12-gallon fuel tank. Docking was no longer embarrassing, and we could now talk while running 10 knots. The rougher the water got, the faster and smoother we would go. Life was good.

A hatch in the foredeck provides access to the bow for anchoring.

But as most of the weight was still aft with either engine arrangement, the EcoCat still squatted underway. One day, Mike Snook—experienced with super-large, high-speed Australian catamarans—suggested transom wedges and end plates as the cure. A 1″ x 4″ wedge was added like a trim tab to the each stern with skeg-like end plates added in line with the sides of the hull to contain the flow. The cat’s tracking was better, even with the previous centerline skegs removed. Trim was now level with clean entry and a very smooth exit. After a prop change, we had the same top speed with cruise speed reduced by 400 rpm for a noticeably quieter boat.

Outboards are designed to mount behind a transom with only the prop exposed below the hull. When centrally mounted on a catamaran, all of the lower unit below the bridge deck is exposed to bow wave convergence with lots of unwanted spray and, perhaps, added drag. We had tried several ideas on previous sailing catamaran but solved the problem on the EcoCat with a hull-mounted streamlined fairing that lets the motor think it’s on a transom.

The EcoCat is quite at home in the broad reaches of Puget Sound that lie in the shadow of Mount Baker.

T he 10-knot cruise speed for our typical three-day, 50-mile round-trips lets us enjoy island life and not lose one day getting somewhere and another getting back. That’s the advantage of a gasser. It’s all about the destination, hanging out, enjoying a nice hike, being in a special place, especially for my wife Barbara and me. My solo trips continue to range farther and wider in all weather conditions.

Ron Mueller continues to design and build small boats and still rows most days in Bellingham, Washington. He started whitewater kayaking in the late ’60s, sailing in mid ’80s, and rowing in the ’90s when he founded Wayland Marine. Ron designed and built the Merry Wherry kits and was the Northwest dealer for Alden Ocean Shells and Echo Rowing until retiring in 2010.

Eco Cat Particulars

LOA/ 18′ (5.50m) Beam/8′ 2.4″ (2.50m) Draft/8.7″ (0.22m) Weight/606 lbs (275 kg) Capacity/1350 lbs (620 kg) Power/15–20 hp Construction/Approx. 400 hours

Plans for the EcoCat , with a digital manual and 16 pages of drawings as BMP or DFX files, come from Bernd Kohler at K-designs . A kit is also available.

Is there a boat you’d like to know more about? Have you built one that you think other Small Boats Monthly readers would enjoy? Please email  us!

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Comments (27)

I would really like to see a drawing of the modifications mentioned in the text. It sounds like the end product was significantly different from the original design.

Tim, JUST ENUF is built exactly to the furnished plans. Obvious additions were the cockpit sides and transom extensions when repowering. Plans are furnished as DXF files which may be printed out for “manual parts layout” or modified in CAD for CNC cutting. I hope this helps.

Form definitely follows function on your well built boat. The 20-hp outboard was a great idea and so were all of the modifications to get everything right.

Pete, thanks for your kind thoughts. Looking forward to seeing you on a Salish Sea beach soon!

I really enjoyed the article in the March issue of Small Boats Monthly about Ron Mueller’s JUST ENUF. Ron’s boat never fails to draw all kinds of attention when he’s pulled out on the beach or running with a group of other boats up here in the north Puget Sound, and looking carefully at his superlative build, one can easily see why. Though I am somewhat of a “traditionalist” at present, this boat looks like it could very well be in my build list sooner rather than later!

I love seeing articles from other Salish Sea folk. The photo with Mount Baker (Komo Kulshan is the name given to it long ago by the Lummi people) in the background is part of my life.

Vince, twins seem desirable but two 8.5-hp motors would use noticeably more fuel then a single 17-hp motor. Remote control would lend itself to a autopilot but complicated. Remember that each catamaran hull has a different turning radius in a turn. My previous sailing Jarcat had rudders set up with Ackerman steering (like a car). That’s probably not really needed for outboards. Just a thought.

I like the look of this craft. What would be the result if you went to twin 8.5-hp outboards which have the electric start and hardware to do twin rigs with remote control? Still the design appears to have a lot going for it. Enjoy it!

I’m just wondering if the deadrise at the end of each original hull was maintained on the 1′ extensions and if so, how the trim tabs were installed.

Mike, deadrise was just flowed out. The trim tabs are a solid wedge at the end of the hull about 4″ long and 1″ thick. An end plate (in line with hull side) contains the water flow for greater effect. The end plate is a skeg-like shape about 12″ by 4″ that provides better tracking than the original skegs on the keel centerline.

Most of the changes Ron made to the design—the hull extensions and other modifications—are incorporated in the plans. There are many ECO’s sailing world wide and it is my policy to update the plans to improve my designs. That applies not only for my ECO line of boats, but the others as well. By the way, I leveled out the deadrise of the extension to 0°.

Do the plans show the unique assembly method in case a builder wanted to have the parts CNC cut? Is the interior of the cabin also coated with epoxy?

Most parts were pre-coated and sanded (at least one side) prior to assembly. The plans are DXF files for display and would need to be, at least, nested for a CNC tool path prior to cutting. After importing to a CAD program, I added an inch in cabin height. Enlarged the windows, laid out cubby holes in the forward bulkhead and designed the cockpit sides with the same curvature used for the cabin. This is a real timesaver and provides great accuracy when having symmetrical parts and provides very smooth curves. The planking and cabin top is best (and easily) laid out directly on existing structure rather then CNC cutting. The construction was completed in just four months while attending to my normal business of selling rowing shells and making kits of same. Painting and canvas was “sent out” and fitting out was, at least, another month.

Thank you very much.

What is the contraption mounted on the forward hatch?

It’s a Nicro Solar Vent Fan. It runs mostly 24/7 as long as its self-contained battery is charged. There is enough leakage through the companionway hatch to keep the cabin dry during winter storage and summer nights when we’re sleeping aboard. We usually slide the main hatch open an inch or two at night (the dodger protects it from rain), and latch the foredeck vent hatch open rather the use the fan. Although fans may be quiet at first, they do develop a bit of noise after a few years.

I did some measuring. I wouldn’t have the ceiling height to flip the hulls over. Is there a real problem building them separately?

Walter, good news, the hulls are built separately. While the hulls were still upside down, I coated them with three coats of epoxy mixed with graphite powder. Those are the black surfaces in the video. This graphite/epoxy mix becomes “bottom paint” and is quite UV resistant, and does not need further painting.

The hulls are then rotated upright, aligned, and a 1/2″ plywood deck is glued to join both hulls. Everything else is built up from this deck—no need to turn the boat over! All of the painting is done from the waterline up. You could paint the bridge deck underside and inner hull sides while the boat is on a trailer.

What brand of windlass was used on JUST ENUF?

An 11-pound Bruce anchor with 10′ of chain is quite easy to haul with an arm-power winch while standing in the forward hatch.

I was looking at the thing below the hatch. Again, thank you.

Appromately how many sheets of plywood were CNC cut?

CNC cutting was used for all bulkheads, frames, cabin sides, cockpit sides, and interior trim— perhaps 10 sheets. The advantage of CNC is symmetrical parts, identical parts for both hulls and very smooth curves and cutout radius. When I had it (now retired six years), my ShopBot was the power tool of choice. Whatever I drew, I could cut and it would fit! Really miss it for my infrequent annual boat building project.

PS: The “thingy” below the hatch was a simple anchor bow roller.

Thank you very much for the information. I have found a local shop that has two ShopBot machines with the capacity of 66″ x 122″.

Greetings Ron, and congratulations on a well built project with very intelligent, yet simple modifications. My question is: Why were not twin 10-hp outboards considered when the twin 5s were insufficient instead of the single 20? Weight, perhaps? And could not the weight vs performance equation also be solved with transom trim tab re-engineering or re-positioning of gas tanks, etc? Love this boat. I am in Biscayne Bay, Forida. We get a chop, we get wind, squalls, hurricanes, etc. It’s a very open bay, but then we get to cruise to the Keys, the Everglades archipelagos, and a million places to explore and gunkhole. I have owned several sailboats here, all with retractable keels—a must if you’re on the bay and want to get off the beaten path of all the Olympic and Biscayne Bay Yacht Racing Association regattas.

Twin 5’s were specified as it was to be a EcoCat. The Honda 9.9 weighs on or about 100 pounds. The Honda rep insists that a single outboard (equivalent in HP to two twins) will always be more economical. I’d suggest today’s best choice would be a Suzuki 25, about the weight of the Yamaha 15/20. It’s said to be more economical and quieter. They sell a 30 (same block size) in the US but it only comes with power trim/tilt so the bracket would be dragging in the water. I hope this helps.

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The Planing Power Catamaran: A Different Kind Of Cat

Advertisement

Planing powercats deliver the high speeds dayboaters and weekend anglers crave — but without so much pounding in choppy seas.

The air cushion ­created between the two hulls dramatically reduces wave impact at running speeds. (Photo: World Cat)

Powercats are different beasts than sailing cats, and the powercats you're most likely to see on your local waters are those in the 20- to 40-foot range (like my 22-foot Glacier Bay). Unlike the big cruising powercats, which are more like cat trawlers with top ends maybe a little over 20 mph, smaller cats have planing hulls that perform much like today's modern powerboats.

Depending on the engine package, there are a few cats that top out in the lower 30s, lots in the lower 40s, some in the 50s, and a few that break 70 or even 80 mph.

While a similar length monohull may have a 40-mph cruising speed in a 2-foot chop, the monohull captain will pull back the throttles and cruise at 30 to avoid being beaten up. The cat guy, on the other hand, may be able to keep on doing 40 thanks to the smoother ride. But having two hulls underfoot does create some interesting similarities in how these different types of boats react to input from the helm. So you'll see a few of the tips here mirror those used for sailing or cruising catamarans. Whatever type of cat you may be captaining, remember the following:

• Center the wheel and use only the throttles to control the boat. Powercats have their engines exceptionally widely spaced apart, and are far more responsive than monohulls when steered via throttles. Generally speaking, turning the steering wheel will only serve to reduce the effectiveness of working the throttles. This, of course, is assuming you have two engines. There are a few rare cats with one engine.
• At identical rpm, the engine in forward will create more thrust than the engine in reverse. So even if the throttles are set evenly when opposed, the boat will likely slide forward a bit as opposed to spinning in its own length. As a result, when attempting to speed up the maneuver it's usually best to favor giving the reversed engine extra oomph as opposed to the one in forward (assuming you don't want to move forward while turning the boat).
• Check the speed and direction of the wind before docking , and remember that some cats, particularly those with low draft, can be blown around more easily than many monohulls as there may be less hull below the waterline.
• When docking in a new slip for the first time with lines that haven't been preset, bear in mind that once you're docked, securing the boat can be difficult in some situations because few powercats have centered cleats. Most will have a single cleat on either side, in some cases obstructed by a bow rail and/or pulpit, which can make crossing lines difficult.
• Never shut those engines down until all the lines are secured . Again, remember that many cats can get blown out of kilter faster than the average monohull, and if you don't have lines preset, it may take a moment to figure out how to best secure them. Many a captain has done a perfect docking job and then shut off the engines, only for a gust of wind to push the boat right back out of the slip before the lines can be tied. Keep those engines running until the boat is 100% secure so you can apply power, if necessary, to maintain position.

Why Two Hulls?

Like all boats, catamarans come with distinct advantages (smooth ride, draft), and areas of compromise (docking, turning). Regardless of design aesthetics, the first question is usually: Why two hulls?

Mike Myers, vice president of product development for World Cat explains: "Catamaran hulls experience little to no drag or resistance to get on plane, resulting in greater fuel economy. They have a steady rise in speed and fuel burn with little to no spikes in fuel consumption."Planing powercats have a unique trait — which many cat lovers consider the top advantage over monohulls — the impact-absorbing cushion of air created by a compression tunnel between hulls.

And when it comes to beam, catamarans' parallel hulls create reliable stability, which helps to avoid heeling and capsizing, and greatly reduces the vessel roll at rest and at trolling speeds.

"Many boats are primarily designed around comfort for the captain. This usually means anyone at the front or sides of the boat takes most of the jostling,"Myers says. "The catamaran-style hull delivers ride comfort, smoothness, load distribution, and stability."That stability draws anglers to powercats of typically 20 to 40 feet; and cruisers to sailing cats 40 to 60 feet and beyond.

— Rich Armstrong

Taming The Cat

When it comes to handling powercats in open waters, the most important thing to remember is that all boats are different. Just as you wouldn't lump the handling characteristics of all monohulls together, the same goes for powercats. But many have a few common traits to consider.

• Some powercats have relatively low buoyancy in the bow compared to monohulls, as many have very narrow hull entries . As a result, in some cases, idling into a sea can allow waves to break over the bow. Gaining some headway so the bow rises a bit and packs air into the tunnel can alleviate the issue.
• Some planing powercats will run smoother at faster speeds than slower speeds, as they compress air in the tunnel between the two hulls. In these cases, speeding up may actually provide a more comfortable ride in some sea states as compared to slowing down. Depending on your boat, its tunnel may result in other differences from the monohull that you may be familiar with. Learning about these will improve you experience.
• Some powercats display a "snap roll,"which is a very fast righting motion that can rock the boat uncomfortably, especially when drifting in a beam sea. In these cases, people who may want to drift often (such as anglers) will sometimes deploy a drift sock off the bow to reduce rocking and rolling.

Photo: World Cat

• In general, powercats are often more weight-sensitive than monohulls, especially when the bow is loaded down . It's always best to be aware of how you're loading your boat, and if the tunnel is slapping or the bow is digging into waves, consider shifting weight aft.
• Some powercats, particularly older models, lean out in a turn rather than banking in. There's no way to eliminate this phenomenon (although trimming up an outboard engine when initiating a turn may reduce it a bit), so it's important to give passengers a warning to hold on before making any aggressive maneuvers.
• "Sneezing,"or blowing a puff of mist out the front of the tunnel that the boat then runs through (getting everyone aboard damp), is a phenomenon associated with some powercats. In many cases, trimming the bow up a bit will significantly reduce or even eliminate sneezing.

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Small power catamaran

Discussion in ' Powerboats ' started by bsmit24 , Jul 5, 2005 .

bsmit24 Junior Member

I am interested in building a small power catamaran. I have not been able to find many plans. There are a few such as Glen L but the tunnel is very low. What are the design issues that I should look at. With of hulls or ratio, with of total vessal or ratio, hieght of tunnel, width of tunnel, shape of hulls, etc. and how these differ depending on whether it is a displacement craft or planning hull? any insight or interesting websites or books would be helpful. Thanks  

nero Senior Member

What do you plan to do with your power cat? Live on it, cruise it, race it. Where are you going to keep it? How big are you and your guests? How much time do you have to build it? Kurt hughes and John Shuttleworth have designs.  

It would be to cruise and fish. My main objective is to get a smooth ride with little power and a relatively small boat (14' to 18'). Nothing to fancy, just a project that I want to do and a new challenge.  

yokebutt Boatbuilder

Bsmit, How about an old hobie 16 with an outboard? You could always replace the trampoline with a rigid platform. Yoke.  

How about a proa? http://www.harryproa.com . Rob Denney Kurt Hughes has several small designs. Rapid building technique also. Plan prices are affordable.  

marshmat Senior Member

Proas are intriguing as sailing craft, yes. I'm not sure if the concept is that good an idea for power craft though. In displacement mode you'd be restricted to hull speed on the ama- not a problem on a sailboat that rarely approaches that speed, but a concern on a power craft. A symmetrical cat would probably be more efficient. For the 14-18' range: I do like Yoke's idea of a hopped-up power-Hobie. If I were building this as a little back-lake cruiser I might actually design the beast myself, be creative.... Now a few rough guess answers to bsmit's questions: Compared to a monohull, a cat's hulls tend to be very slender. For planing, you typically keep the outer hullsides parallel while narrowing the tunnel significantly (the air in the tunnel then helps lift). Hull bottoms can be V or half-V, and are often asymmetrical (it's a complex art...). For displacement hulls, it's usually more like two separate boats bolted together- each slim and sleek. Hullforms- near infinite variety. The stability comes from the wide spacing between the hulls. Tunnel height is determined mostly by the waves you'll run in and the tunnel should be high enough that the waves don't slap it too much. The art of hull design is as complex or simple as you want it to be. If you're fishing little back lakes, this could be a fun one to experiment with. If you're a big-water type it might be better to look at stock designs.  

JEM Senior Member

Take a look at http://www.davesflatcat.com/ . I think Dave is a member on this board. Last I heard, he's willing to share the plans. Matt - JEM Watercraft  

Thanks guys. I have a 40hp yamaha so I would like to try a planing hull first. I did find one that I liked on http://www.constellationyachts.com/skiff.htm . The davesflatcat is interesting but the tunnel is very low and the hulls have flat bottoms. I currently have a bateau so I would be more interested in something that would take a little rougher water. I also like the twin vee 17 but I really want to build the boat. There just does not seem to be much out there.  

Tim B Senior Member

If you tell me what you're after (E-mail me - [email protected] ) I'll draw up some ideas/plans for you at reasonable cost. I can't easily post you drawings, but we can work in electronic form, no problem at all. Then you can either print the plans full-size, or just take measurements off them. I will supply full measurements for each part. All the best, Tim Brocklehurst.  

Jimboat Senior Member

Tunnel boat Design Check out my website for tunnel hull designs and methods...  

Aksan Junior Member

I do not know all your intents but , here is another thing you can look at Full catamaran centerconsole 13 ft long , 30 - 50 HP range. You can get one and rig your own engine to it: Aksano Catamarans aksano.com The boats do 25-45 MPH and are amazingly stable and eye catching..  

kengrome Senior Member

It would be to cruise and fish. My main objective is to get a smooth ride with little power and a relatively small boat (14' to 18'). Nothing to fancy, just a project that I want to do and a new challenge. Click to expand...

Hmm.. There are alot of desigs out there that will effectively slice throught the water and use very few HP. But the key point in Design is,that is light years away from actual fishermans visuals.. I mean that want the efficiency in numbersn but they want it to look cool. You also have to fin means of building this thing so that is simple to fabricate. If you can design something that is COOOOL to look at , plus it is efficient, then you have a CHANCE in the US boat market. Now if you are doing this for your sake just to buil one off, then it is great, I would give myself more space to move about and less seats, bench seat would be just fine in this kind of set up... Oz.  

Squidly-Diddly Senior Member

How about Livingstons? http://www.livingstonboats.com/ They seem to be the standard 'small power cat'. Anyone ever put one through its paces?  

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Livingston VS Other cats / Aksano Catamaran Well I build the Aksano cats but I think the reason they did not catch up a lot was they were too plain, too simple lacking style and speed. I know a few of people who bought ours product www.aksano.com after owning a Livingston, things I heard was; Lower grade appeareance, engine cavitation, cracks / heirline fractures appearing in areas gunnel was bonked to the dock Comparable F3 to a 13 ft livingston goes faster despite the fact that it weighs more smoothness of the ride is equivalent, the quality is comparing apples to oranges, we are lightyears ahead of that concept. Dave livingston very nice guy, was the one who started the company, very smart men, ge is getting a litlle old now his sons now run Martini boats. The company livingston is now located in western shoreline of Washington, veyr slow in business.  

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A small power catamaran may be easy to get around to handle lines around the dock, and is just more manageable all around for a cruising couple than a boat that’s much larger. That said, our patented proa hull design means Aspen owners get all the benefits of seakeeping, straight tracking, and efficient cruising, without paying more for dockage.

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9 Best Power Catamarans For Rough Seas and Coastal!

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Power catamarans are gaining popularity in the cruising world thanks to their enhanced stability and ease of operation. They’re ideal for coastal cruising but can also be used for ocean crossing thanks to their stability and speed.

Here are some of the best power catamarans on the market:

• Fountaine Pajot MY6
• Nautitech 47 Power
• Horizon PC74
• Lagoon Seventy 8
• ArrowCat 420
• Sunreef Supreme 68

In this article, I’ll review some of the best power catamarans out there. I’ll also go over the main features of different power cats and if they can handle rough weather. 

But before we dive in, let’s get a better understanding of what power cats are.

Table of Contents

What Is a Power Cat?

A power catamaran (power cat) is a motor-powered boat that, unlike traditional boats, has two hulls connected by a bridge deck. These vessels are more stable than monohulls because of their wide base.  

Power cats also don’t have a leaded keel to weigh them down, so they’re pretty lightweight and fast. The lack of a keel also means that power cats are more suitable for shallow waters.

They feature large engines designed to handle their bigger bodies and weights, and serve different purposes, like fishing, cruising, or crossing rough seas. In addition, each hull has a separate engine which makes them more maneuverable, especially at turns and tight spaces.

Power catamarans don’t have sails or masts and get all of their power from the combustion engine (or electric motor), unlike their sailing cousins. In addition, these vehicles are much easier to steer because of their increased stability.

Power catamarans have more interior and exterior space thanks to their multihull design, making them perfect for cruising and liveaboard . They also have ample space for storing everything you need on a cruise without worrying about weighing it down. Catamarans offer increased privacy as well because each hull houses one sleeping area, separated by the living area between them.

Are Power Cats Good in Rough Water?

Power catamarans are good in rough waters particularly because of their multi-hull design. Their wide base makes them stable, and their high speed allows for outrunning bad weather.

Power cats that feature a high bridge clearance, will handle rough waters effortlessly. With the added height, you won’t experience pounding and slamming even in heavy waves, allowing the crew to easily control the vessel in challenging situations.

These boats are also faster than their sailing counterparts, which means they can get you out of rough waters quickly.

In addition, since catamarans are large and tall, maneuvering is easier because you have a better view of the surroundings. Additionally, you can steer from the interior cockpit (on certain models), making it easier to control the vessel in bad weather.

Finally, although a power cat doesn’t have a keel to help it right itself in case of capsizing, it will still float easily because of its positive buoyancy.

Are Power Catamarans More Efficient?

Power catamarans are more fuel-efficient than monohulls because they don’t have leaded keels. While keels are designed to offer stability by weighing down the vessel, they increase the wetted surface and thereby add drag.

Due to the catamarans’ narrow bow entry, there’s lower resistance, leading to smoother acceleration and greater fuel economy in catamarans. In addition, power cats show fewer spikes in fuel consumption in a single power band, especially because of their smooth acceleration and fuel consumption.

The figures reported by cat owners or manufacturers show that power cats have the best power-consumption-to-speed ratios.

That being said, you can improve fuel efficiency by maintaining lower speeds; studies have shown that speed can be the most important factor in fuel efficiency, regardless of the number of engines or hull types. 

Now that you have a better understanding of power catamarans, let’s take a look at the ten best models on the market.

1. Leopard 53

This 53ft (16.19m) power cat is the fourth generation of the widely popular Leopard catamarans, and brings with it all the great features from her predecessor, the 51. 

Although the 51 was the company’s best-selling cat, they added these features to the 53 along with new ones to repeat its success. For example, they have built an enormous saloon, flybridge, and galley by removing the foredeck cockpit in the 51 PC, making it 30 percent larger than the previous model.

This model comes with three or four stateroom layouts, with the 3-stateroom version featuring an owner’s stateroom, two sinks, a loveseat, and lots of storage space.

With two Yanmar 370 hp engines, a maximum speed of 22 knots, and a cruising speed of 17.5, you can enjoy a magnificent ride, whether it’s long-distance cruising or a fun night out with friends.

2. Fountaine Pajot MY6

This luxury power cat is 44ft (13.40m) long, making it super spacious and suitable for families and big parties. With its spacious flybridge, sunbathing lounge, and enormous galley, it’s nothing short of a second home on the water. 

You can steer the cat from the saloon or the 21sqm (68 sq ft) flybridge which features a sunbathing lounge, a pool, and a galley.

This motor yacht continues to delight with its luxurious combination of privacy and pleasure, with views of the sea in almost every interior space. With three cabins, two bathrooms, six cabin beds, ample storage, and a kitchen that opens into the cockpit, you can enjoy practicality and luxury in one place.

The MY6 is exceptionally seaworthy and stable thanks to its wave-piercing hulls and Volvo IPS engines.

Like all power cats, it has straightforward steering, enabling you to control this beast even in the roughest circumstances.

3. Nautitech 47 Power

Powered by dual Volvo Penta D4 engines, this model can output 225-300hp, reaching a maximum of 22 knots and a cruising speed of 18-20 knots . This 46′ 8″ (14.23m) long power cat comes in three or four cabin versions, depending on the customer’s preference.

No matter which layout you choose, you’ll get a spacious, luxurious, and comfortable catamaran with panoramic views from the cabin. The sleek, streamlined exterior design ensures elegant sailing and seaworthiness.

It’s easy for passengers to navigate the deck thanks to its seamless design that connects the saloon to the cockpit and the rear deck. The stern features a big swimming platform that can also accommodate a tender. The cockpit is usable in different weather conditions thanks to the clear covers wrapping the whole area.

This efficient catamaran promises long cruising for big families and groups with two 300L water tanks and a pair of 645L fuel tanks.  

4. Horizon PC74

The Horizon PC 74 is another luxury power cat that can give you the comfort of your home on water. This 73′ 9” (22.48m) long power cat with a 2,000gal (7570L) fuel tank is an enormous vessel that can accommodate more than 14 people.

The enormous hardtop on the three-piece windshield, the teak dining table, the U-shaped bar, the sun pad, and the swing-out stools all guarantee that you’ll have the luxury cruising experience of a lifetime.

This vast and wide catamaran allows you to access the aft deck from the flybridge via a curving staircase. The vast aft deck has a ten-person dining table, a wet bar, and storage space. You can separate the interior and exterior spaces through sliding glass doors and make the space appear bigger by opening them.

Reaching a top speed of 23 knots and a cruising speed of 19 knots, this enormous catamaran was built for efficiency and practicality.

5. Lagoon Seventy 8

This 78’1″ (23.80m) power cat with two 494 HP engines and a 2246gal (8500L) fuel capacity is one of the largest power cats on the market, offering both comfort and reliability. The enormous flybridge can feature a jacuzzi, a sunbathing area, a large foldable dining table, and a hardtop with a moveable roof. However, you can customize the flybridge based on your preferences.

The designers have compromised nothing in terms of elegance and high-quality materials with top-of-the-line finishes and interior paneling to create the kind of luxury you want.

The saloon is huge, well-ventilated, and separated from the exterior by glass doors and panoramic windows.

But what sets Lagoon Seventy 8 apart from other power cats, in addition to its enormous size, is the wide choice of layouts. You can choose between five different versions, all offering the same amount of storage space, living and sleeping area, and privacy.

Additionally, some versions are fully customizable, allowing you to pick every detail to your liking.

6. ArrowCat 420

This 41′ (12.73m) long express cruiser is a semi-custom catamaran with two-stateroom and three-stateroom layouts. The ArrowCat 420 is designed and built with comfort and strength in mind, and capable of handling rough waters safely.

The two Suzuki 350 hp engines give this model a maximum speed of 40 knots and a cruising speed of 20 knots.

The streamlined design and the angled hulls ensure the vessel cuts through the waves effortlessly, making it easy to maneuver.

The fully-equipped head features an electric toilet, a shower, sink, and mirrors, coupled with a dining table, floor storage locker, and teak-finished floors. This cat is built to combine luxury and comfort for both onshore and offshore cruising.

7. Bali 4.3

This 43′ (13.1m) power cat is made for ocean crossing in mind. With five different layouts featuring different combinations of cabins and heads, the company ensures you’ll get the kind of setup you want. Regardless of the layout, this cat offers a spacious master suite with a large double bed and other private sleeping quarters.

You can quickly add to the overall space by removing the adjustable glass doors to merge the cockpit with the saloon.

A feature that sets the 4.1 apart from its predecessor is the fixed aft deck between the hulls, which provides a passageway and eliminates the need to go from one hull to the other without entering the cockpit.

8. Sunreef Supreme 68

According to its designers, this model was built with a radical concept in mind while staying true to the company’s promise of building the most comfortable and spacious power cats in the world.

One of the greatest features of the Supreme 68 is its aft garage that houses a 5m (16 ft) tender and two jet skis in addition to other water toys.

You can also transform the aft to a large platform for water sports by lowering the garage door.

The four-stateroom layout features ample storage, ensuite guest cabins, queen-sized beds, and TVs to create a memorable stay. The white and beige furniture with chrome details and floor-to-ceiling glazing create a soothing atmosphere that blends with the practicality of the well-equipped galley. 

However, if you’re looking for something different, you can opt for a customized model from three different layouts.

9. Hudson 48

The sleek, diamond-cut design of this 46.46’ (14.16m) long power cat is usually the first thing to catch your eye.

It’s a light displacement cat that ensures fast cruising with a top speed of 24 knots and cruising speed of 8 knots thanks to the two 370hp Yanmar V8 engines.

The three-cabin layout features a master stateroom with a spacious and well-ventilated design made possible via the three overhead windows and opening deck hatches.

The saloon’s enormous helm station allows for comfortable and safe accommodation, making it great for rough waters and bad weather conditions.

This model also offers a few entertainment options with its large TV systems and mood lighting. The storage areas and the full-sized walk-in wardrobe give this model a comfortable, homely setting.

Here are Some of My Favorite Catamaran Cruising Resources

Thank you for reading this article. I hope you found it helpful as you hopefully start your sailing adventures. Here are some resources that I use as a sailor that I hope you’ll also find helpful. These are affiliate links, so if you do decide to use any of them, I’ll earn a commission. But in all honesty, these are the exact things that I use and recommend to everyone, even my own family. Sailboats: If you’re looking for the best boat to suit your needs, I would recommend a catamaran. If you’re interested, I can show you the differences between catamarans and other types of sailboats .

Books:  For getting started, I really like  Cruising catamarans made easy . It is actually a textbook from the American sailing association; it is used to get a cruising catamaran certification. There are some other great books, and I have compiled a list of books about cruising catamarans that you will find useful.

Communication:  Being out on adventures, whether it be sailing or climbing mountains, good communications are essential to being safe. I recommend two things Google fi (incredibly simple cellular data all over the world) and Garmin inreach mini (for text and voice in remote areas without cell coverage)

Sailing courses: Online sailing courses are great for beginners starting out their sailing career; it’s an efficient way of learning the basics of navigation, throttle controls, and maritime safety. I suggest starting with two free courses from NauticEd .

To see all my most up-to-date recommendations,  check out this resource  that I made for you!

Owner of CatamaranFreedom.com. A minimalist that has lived in a caravan in Sweden, 35ft Monohull in the Bahamas, and right now in his self-built Van. He just started the next adventure, to circumnavigate the world on a Catamaran!

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