Multihull Structure Thoughts

Discussion in 'Multihulls' started by oldmulti, May 27, 2019.

  1. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    The Wapa 50 is a Philippe Rivière (naval architect) design and built by Multicap Caraîbes shipyard. The Wapa 50 is a fast cruising trimaran built in plywood and timber. The Wapa 50 is 49.5 x 32.9 foot with a weight of 17,900 lbs and a displacement of 24,700 lbs. The jpeg spec sheet says a weight 16,800 lbs and a displacement of 21,800 lbs. take your choice, I trust the heavier numbers. The aluminium mast is 59 foot with an upwind sail area from 1,300 to 1,460 square foot and a downwind sail area of up to 1,970 square foot. The draft is 3 foot over its fixed low aspect ratio keel on the main hull. The rudders are float based. The hulls have chines and have good length to beam ratio’s. I cannot translate the jpeg French article so cannot comment on performance beyond the above numbers indicate a fast powerful trimaran that could easily do 250 mile days and peaks at over 20 knots.

    The accommodation is 3 double berths and 3 single berths with a large galley and seating area in the main hull. There is a large toilet area forward of the mast cross beam. This is a roomy tri for its size.

    The tri is built with plywood panels taped together with 800 gsm tapes. The main hull has a thick wooden keel, 3 stringers on hull sides and underwing panels stringers. My guess is 12 mm bottom panels, 9 mm sides, underwing and cabin panels covered with glass cloth and epoxy. The cross beams are box structures with metal waterstays. The beams look removable for disassembly or assembly for EG moving from a build site to a launch site. The jpegs has a diagram of a section of the main hull. The beams may have carbon fibre reinforcement.

    Sorry I could not find better jpegs but the design is still available on Philippe Rivière web site: https://philipperiviere.com/
     

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  2. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    The Dutchcat 12 is a hybrid powered cruising catamaran that was designed by Vripack from the ground up. The cat has 2 hull shapes depending upon the intended purpose. The ‘Comfort’ version has a round bilge form and long shallow keels, similar to a sailing yacht, and is designed to run at lower speeds with smaller engines. The ‘Sport’ hull is a more traditional powerboat form with spray rails and tunnelled props for higher speeds, topping out at 22 knots with bigger motors. Above the waterline is basically the same vessel.

    The Dutchcat is 41 x 16.1 foot with a displacement between 26,400 lbs and 26,900 lbs depending on the hull shape and engine options. Draft is 2.75 foot. The all electric power source uses twin Kräutler 48V 10kW (14hp) or 15kW (21hp) motors connected to conventional shaft drives for a maximum speed of 8.5 knots and a cruising gait of 4 to 6 knots. Gel traction 48kWh batteries are standard, with Lithium batteries an option. DutchCat claims about seven hours of cruising at 5 knots and about ten hours to recharge from a 16A supply.

    Pure diesel is an alternative. Comfort-spec boats rely on a pair of Yanmar 3YM30 3-cylinder 29hp engines to yield about 11 knots maximum and cruise at 8 knots. Opting for the Sport hull configuration allows twin Yanmar 4BY3 150hp engines to boost maximum speed to about 22 knots.

    The electric motors use the same engine controls as the diesels, so it’s just a case of switching off the Yanmars, engaging the electric motors and then throttling back up. Two hulls mean two bow thrusters. a pair of 55Kgf Vetus units. Test reports say under electric power the boat is very quite with the only sound is the gurgling of water around the hulls. The Dutchcat in electric mode is best suited to inland waterways but the cat can travel offshore in appropriate conditions.

    Theaccommodation has 2 2 berth cabins forward with attached ensuite toilets. The bridgedeck has the steering position, big galley, dinette and seating. The glass door between the cockpit and main cabin can be fully opened to create a large open space. There is seating on the foredeck for a great view of the world. There is full headroom throughout. The engine rooms are spacious.

    The construction is a full female mould foam glass structure. The jpegs give the idea to an interesting design.
     

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  3. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    The following is a NZ Dan Leech designed outboard powered cruising catamaran that can be built at home or professionally. The L925 is 30.3 x 11 foot with a waterline length of 24.75 foot. The displacement is unknown but I would guess about 10,000 lbs. The length to beam on the hulls is about 9 to 1. It draws 1.6 foot when engines are up. It is powered in this build by two 90 HP four-stroke outboards that spin 14×12-inch props and provide more than enough power to push the low-drag hulls. The fuel tanks carry 300 litres. The top speed is 22 knots and can cruise at 5 to 17 knots depending on the economy required.

    The L925 featured here is a very well done home build that took 4000 hours to do, as the interior jpeg shows. The accommodation is a forward master cabin with a king size berth and associated ensuite. The main cabin has a forward steering position, large galley and seating area. The cockpit is accessed through folding glass doors that allow a semi integrated saloon cockpit space. The open aft cockpit allows access to the outboards and provide a landing point for dinghies or pulling in fish as required.

    The L925 is built of plywood glassed over both sides, timber and some foam inserts in the underwing. CNC files for plywood cut outs were provided at a local furniture manufacturing factory who produced 2 trailer loads of plywood panels delivered to a suburban garage. This kitset style system simplifies the construction and speeds up build time, but still allows for a high quality finish while maintaining the underlying strength and stiffness of composite construction. The hulls are constructed of 12mm marine ply with an epoxy e glass laminate inside and out. This is reinforced with 12mm frames and 12mm doublers in load-bearing areas. The pilothouse is 9 mm ply and underwing is 48mm ply/foam/ply sandwich. The decks have an epoxy e glass laminate as well. There are strong collision bulkheads in the bow and deep bilges to keep any water that does come aboard away from the interior. There is virtually no metal fastenings in the entire build as everything is taped together.

    The owner deliberately keep the boat simple with large open spaces in preference of putting a lot of unused bunks and cabins in the cat. The older owner couple wanted to do several weeks of comfortable cruising meeting people for day cruising along the way. The jpegs give the idea of a well built cat.
     

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  4. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    The following is about a power catamaran that is built for serious ocean work. The Wildcat 40 is 40 x 16 foot with a weight of 27,000 to 31,000 lbs depending on the purpose of the cat. The Volvo/Cat/Yanmar engine options can have a total of 250-500 HP with Twin Disc 5126 gearboxes. The length to beam is 6.8 to 1. The Wildcat 40 has a draft of 4.2 foot. Operational speed are between 16 to 25 knots with a maximum speed of 30 knots.

    The accommodation can vary according to use. One version is a crew boat for 12 or a work boat for a specific purpose. The basic design could also be converted to a cruiser if required. The cat is built by Safehaven boats in Ireland and is built from fibre glass with foam inserts as required.

    Now we get to the interesting part and the reason for this item. These workboats need to work in many sea states and are designed accordingly. “Due to the slender nature of the hulls, in choppy conditions vertical accelerations are much reduced giving a gentle ride and motion. However previously the biggest disadvantage of the older type of catamaran hull which featured very fine sections forward with little reserve buoyancy, giving a very smooth ride in short sea states but suffering badly in ocean swell conditions due to slamming on the bridge deck. This shortcoming has been solved with much fuller forward sections and much greater buoyancy, giving the hull the necessary lift to prevent slamming on the bridge deck, allowing higher speeds to be maintained into larger ocean swells. Due to the low resistance of the slender catamaran hulls, performance is excellent, especially at moderate speeds up to 20kts.”

    Look at the jpegs. This is the Wildcat 40 being tested in a force 7 to 8 winds (30 to 40 knots) and seas. If you need to run for shelter in these conditions, you may find it a pretty wild ride. The Safehaven Wildcat 40 is deliberately designed to handle these conditions. Please understand serious offshore cats occasionally need to work in these conditions but as a cruiser you do not have to push as hard as a workboat that has a schedule to meet.

    The jpegs give the idea. There is also a video on the web somewhere of this trial.
     

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  5. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

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  6. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    Bagoù 7.0 is a powerboat that is aimed at day use for up to 12 people and is designed by Julien Marin. The Bagoù 7.0 is 24.1 x 9.2 foot with a weight of 1900 lbs. The length to beam on the hulls is 12 to 1 with a draft of 1.5 foot. The hull is optimized to sail between 5 and 15 knots. Power options are two by 2KW or 6 KW or 10 KW or 50 KW Torqeedo electric outboards. There is an option for petrol outboards but the cat does not need high power to reach its designed speeds.

    A test reported “With two Torqeedo Cruise 10.0, it cruises between 6 and 10 knots and could reach 15 knots at maximum speed with different propellers.” A second test report with 2 X Cruze 10s with 10 kW / hours of batteries for each motor “sailed for about 5 hours at 6 knots with 7 people on board for a very pleasant ride on a beautiful sea with a slight chop.” The performance of the Bagoù 7.0 with 2 x 25 hp petrol outboards produced 2 to 18 knot speeds. The hulls are left partially empty to accommodate batteries or a fuel tank for internal combustion engines.

    The accommodation is a dayboat with seating for up to 12. There is a small toilet area in a hull and a small cooking facility in the large cockpit. The freeboard is very high which will ensure minimal water or spray aboard and no one will fall over the side. The aft platform allows easy access for boarding, outboard access or EG bringing fish aboard. As an option, a retractable and foldable Bimini and a sun canopy is offered with solar panels on the roof to assist in recharging of the batteries.

    The boat was designed and build from timber and plywood covered with glass and epoxy. The builders did not want to invest in moulds and the French have no problem with buying production plywood boats.

    The cat lives up to its promise of being a day sailor with the people on board enjoying the absence of noise. It feels like being on a sailboat. The jpegs give the idea.
     

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  7. Burger
    Joined: Sep 2017
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    Burger Junior Member

    I've become more interested in affordable-sized efficient powercats as I get older. Local Whitsunday island cruising without the operating/maintenance/cost hassles of a sailboat. (Many years ago I was part-owner of a Wharram cat.....)

    Oldmulti, may I suggest a review of Richard Woods' Skoota 28/Aegean 30 boats?
     
  8. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    Burger requested some information about the Skoota 28 and Aegean 30 power catamarans designed by Richard Woods. Richard on his website has written extensively about his personal Skoota 28 which he has cruised for over 6000 miles around US and Canadian waters. The cruising log is at Richard and Jetti's Cruising Log http://woodsdesigns.blogspot.com/

    The Skoota 28 is about the smallest power catamaran that has good accommodation for a couple to do extended coastal and limited offshore cruising in the right conditions. The Skoota 28 is 27.9 x 13.8 foot with a build weight of 4000 lbs and a launch weight of 5060 lbs. The displacement is unknown. The length to beam of the slightly asymmetric partially flat bottom hulls is 13 to 1. The underwing clearance is 1.45 foot. The engine power is two 20 to 60 HP engines.

    The whole boat is modular, simply bolted together so can be transported legally as one (non oversize) load. But it isn't trailable, you need help to assemble it. The concept is the normal one: "drinks for six, meals for four, sleeps two". There is a queen size (5ft x 6ft 4in) bunk next to an associated dinette. A good size galley with 6.3 foot headroom and a separate head shower. This is a practical and useful layout for 2.

    Richard said the Skoota 28 is designed as an economic cruiser with a cruising speed of 10-12 knots. Our Skoota is fitted with twin 20hp outboards yet still does over 16 knots flat out. Twin 60hp are the maximum recommended for speeds in the mid 20's. A quote of his Skoota 28 “In early May we motored to Vancouver (see the Latest News for May 2013). Getting there was a 'windward bash" but on our return trip the wind had dropped. We motored 38 miles in 3 hrs 20 minutes, so averaged over 11 knots, and used just 5gal of fuel (over 7mpg). That is an accurate amount because we are still using the 3 gallon tanks that came with the engines. When I got back to Saturna I refilled those tanks with a 5 gallon can and still had a bit left over.”

    “I was initially worried about the engine noise from the exposed outboards. So, I used a Db meter to check the sound levels. This is what I recorded: At tick over speeds 55 db, at cruise 75 db, at full speed 81 db.” This is about the sound levels in an average car. He uses noise cancelling headphones if he needs less sound.

    And a final quote “As we always say "navigation is easy, our destination is always dead into the wind". That applies even on a powerboat and we had to "bash to windward" the whole time. Occasionally in surprisingly steep waves, which on one day were even breaking right over our new windscreen, fitted nearly 2.5m (9ft) off the water.”

    The build is basically plywood timber construction with glass epoxy covering. The hull has 9 mm and 6 mm panels. The main cabin unit provides a crossbeam structure element and there is a rear box crossbeam. Stringers are 50 x 25 mm on ply bulkheads with timber edging. The basic material list is:

    60 sheets 6mm plywood
    25 sheets 9mm plywood
    450 board feet 1in x 6in timber (140m of 25mm x 150mm)
    36 gal (140kgs) epoxy
    5lb (2kg) wood flour or similar filler
    5000 stainless steel countersunk screws 1in x 6 guage
    filler/paint as required

    This is a serious, proven cruiser that has cruised in some very rough water. The Skoota 28 is an economical cat that an comfortably travel at 10 plus knots when condition allow or get up to 8 miles per gallon of fuel at 8 knots, this is about 0.5 litres per mile. Very good design. I will talk about the extended version the Aegean 30 tomorrow.
     

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  9. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    The Aegean 30 is an updated version of a Skoota 28 power cruising catamaran by Richard Woods. A Greek client wanted more accommodation, so Richard modified the hulls to have standing headroom and single berth in each hull whilst still being demountable and trailable (once demounted).

    The Aegean 30 is 30.1 x 16.5 foot with an empty build weight of 5,500 lbs and a launch weight of 7,000 lbs. Again, the loaded displacement is unknown. The length to beam of the symmetric semi flat bottomed hull is 10.2 to 1. The draft is 1.2 foot over the hull. The underwing clearance is 1.8 foot. The designed power is two 40 to 60 HP outboards that will give a top speed of 16-20 knots depending on engines chosen with a cruising speed of 10-12 knots.

    The main cabin (with 6 foot headroom) layout is similar to the Skoota 28 but the hulls have been lengthened and have a higher freeboard to provide headroom and space for a single berth. This cat can act as a liveaboard coastal cruiser for 4 people. Again, as mentioned the boat is demountable to allow transport to new locations or from a build site to a launch site.

    2 extra feet does not sound much, but lets look at what it truly costs. Notice the build weight is 1500 lbs or 37% heavier than he Skoota 28. That is 1500 lbs more materials to buy, shape, glue together, fair and finish. The hulls are relatively fatter to accommodate the single berths and provide buoyancy to support the extra weight. Result, you need two 40 HP outboards to push the Aegean 30 compared to two 20 HP outboards to push the Skoota 28. More fuel required to achieve a similar cruise and top speed. Yes, the 2 foot wider overall beam reduces the wave drag between the hulls but the asymmetric hull shape on the Skoota 28 was assisting in reducing the wave drag anyway.

    The Aegean 30 is again a plywood timber construction (with a glass cloth epoxy covering) is of a similar structure to the Skoota 28. Because it is wider and heavier some of the ply and timber dimensions would be upgraded slightly in the beam area.

    In summary, the Aegean 30 has 2 extra berths and is a slightly longer and wider cat that will be slightly more sea capable. BUT the Skoota 28 will achieve similar sea performance, similar speed and be more economical at sea and cheaper and faster to build. The downside of the Skoota 28 is the 2 berths versus the Aegean 30 4 berths.

    This is personal choice. I would build a Skoota 28 because any liveaboard would only be my partner and I. The cat doesn’t need an extra berth. But if you have kids or have a need for a friend or 2 to stay for a while, choose the Aegean 30.

    Sorry about the limited jpegs.
     

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  10. 23feet
    Joined: Dec 2014
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    23feet Junior Member

    Hi Oldmulti,
    This is my boat. The beams are very stiff and light and I'm surprised that more builders don't go this way. The pictures of the Tiki moored in an onshore gale are also mine. The pitching effect is exaggerated as the water depth is 2 feet, and the mooring line is only 15 feet long. The waves are almost breaking and the boat is being jerked forward by the short scope. The boat does not behave like this in a seaway.
    23feet
     
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  11. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    I have been asked to compare the Leech designed L825 power cat with the Skoota 28. The L825 is 27 x 9.8 foot with a weight of 4,500 lbs. The hull length to beam is 10.4 to 1 at the waterline. Draft is 1.3 foot with engines up. The underwing is 1.5 foot above the waterline at the stern. The power requirements initially stipulated was two 20 to 60 HP. To quote Leech in a NZ boating magazine when his own boat “Kokomo” was tested “The L825 will accommodate twin motors up to 60hp; any bigger and the weight gain and associated extra engineering of the hull would pretty much negate the increase in performance.” Next, we find a NZ L825 “Ostra” has twin Yamaha 115hp four-stroke outboards.

    The accommodation layout has a double berth forward across the wing deck, 2 single berths in the hulls and a toilet. The main cabin has a few layout options but contains a galley, dinette and steering position. The main cabin and cockpit are joined by a sliding glass door to provide a larger space.

    The structure varies depending on the HP on the stern. “Kokomo's” (Leech’s twin 40 HP) hull is constructed of 12mm marine ply with an epoxy E-glass laminate inside and outside. This is reinforced with 12mm frames with 12mm doublers in some areas. The pilothouse uses 9mm plywood; the cockpit sole and hardtop are in 18mm plywood, and all decks have an epoxy E-glass laminate as well. The seams etc are taped together.

    “Ostra” (twin 115 HP) hull bottom comprises three layers of 6mm meranti BS 1088 marine plywood. Sides are 12mm gaboon BS 1088 marine plywood and the hull frames are 12mm BS 1088 plywood with a 12mm plywood doubler in certain areas. Deck and cabin are a mix of 12mm and 9mm BS 1088 plywood. Hulls are sheathed in a generous E glass/epoxy laminate inside and outside, while the hardtop’s sheathed with the same laminate on the outside. It’s all been faired and finished to a high standard.

    “Kokomo's” twin Parsun 40hp two-stroke outboards that spin 11.8-inch props and provide more than enough power to push the low drag hulls quickly up to 19 knots. At cruising revs of 3500rpm she sits on 14 knots.

    “Ostra” has twin 115 HP outboards with twin 200-litre fuel tanks offer an effective range of around 180 nautical miles, but for game fishing this would increase to over 250 nautical miles at trolling speeds. Leech says the planning hulls give a top speed of 35 knots. Cruising the L825 gets to a destination comfortably with great economy (1.2L/NM at 14 knots). The optimum cruise speed of 23 knots at 4,500rpm with a fuel consumption of around two litres per nautical mile.

    Compared to the Skoota 28 we have 2 different boats with different missions. The Skoota 28 is a liveaboard cruiser for 2 for long distance travel. The Skoota 28 has displacement type hulls that slice through the water with a length to beam of 13 to 1 using EG twin 20 HP engines consuming 0.5 litre per mile at 10 to 12 knots.. The Leech L825 is aimed at short term cruising for 4 with planning hulls with a length to beam 10.4 to 1. The L825 has EG twin 40 HP engines that consume about 1 litre per mile will cruising at 14 knots.

    The peak speed of the L825 is 35 knots, the peak of the Skoota 28 is about 23 knots if appropriately powered in each case. And here is the real difference. This is a choice between getting places very quickly at the expense of fuel consumption. The sea motion would also be different, the L825 will push over the top of seas, the Skoota 28 will act more like a sailing cat motion.

    The materials used in the Skoota 28 hulls are 6 mm ply, the L825 uses 12mm and in one option 18 mm ply. Shifting around 18 mm ply sheets requires some muscles. I suspect the build time would not be to different if you started from a set of plans but you will be using more glass and epoxy in the L825.

    Define your intended use then choose the appropriate design to suit. Both these boats perform well and can achieve impressive outcomes. The PDF shows the internal accommodation layout. The jpegs give the idea.
     

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  12. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    The VAKA MOANA (Boat of the Ocean) is the largest canoe built according to drawings made by James Cook around 1770. She is a double masted traditionally based Polynesian sailing canoe and outfitted with solar powered propulsion system. She is made for open sea transportation over long distances with the larger goal of reviving traditional Pacific culture and environmental awareness. The seven Vaka Moana that participated in the journey are Fa’afaite, Gaualofa, Haunui, Hinemoana, Marumatu Atua, Te Matau A Maui and Uto Ni Yalo. All canoes were built in 2009 in New Zealand’s Salthouse Boatyard and are now operated by local voyaging societies in Tahiti, Samoa, New Zealand, Cook Islands and Fiji.

    The VAKA 72 x 21 foot weighing 31,400 lbs and capable of carrying 10,000 lbs. The sail area in the spirit schooner rig is 1033 square foot on two 51 foot masts. The draft is 6 foot over the centreboard. It is powered by a 60 HP outboard or two 10 KW electric motors.

    The Vaka is a combination of the old and the new. The accommodation is a 12 x 10 foot “hut” on the wing deck which contains sleeping berths for 8 people and other basic accommodation. The “galley” is both on deck and some interior storage. The on deck space is large for sailing handling and steering control.

    Good tradition so far. Now the structure. Resin infused foam and e-glass hull structure built out of a female mould built by Salthouse boats in NZ. Each hull is lashed together using 12 wooden beams and ropes.. The deck is timber slats to allow water to drain from the deck. The steering arrangement is an Oar that requires up to two people to control. The hulls have a very non traditional retractable centreboard for better upwind performance and control.

    The sailing performance is about 6 to 12 knots cruising with about a 115 degree upwind capability. The intention of these boats is to provide low cost, low environmental impact transport around the pacific between many small islands. The jpegs give the idea.
     

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  13. 2flit
    Joined: Sep 2007
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    2flit Junior Member

    RE: Farrier F36/39
    So the above is from me.... Since I wrote this during a major refit in Opua, New Zealand around Dec 2019.... We've taken about 800 pounds of gear (including removing Ian's aft facing lowers and cap shroud's, gone to all SK-75 rigging; eliminating about 20 meters of chain, and 200 M rode; and so on. We've lightened the old gal up. We recently sailed back up from the North Island and had a 300+ mile day and averaged 243 miles a day over three days. The boat was able to sustain speeds just barely over 20 kn without any surfing and did so in 4 meter beam-on seas. The design is remarkable in her sea keeping abilities as the ride (in the cockpit area) feels like it smooths out and the boat acts like she's on rails.
    We still have not gotten rid of the watermaker , bicycles, or our fridge.... and my spreadsheet has us at about 3,385 lbs added weight (stuff other than indicated on the plans). So the advice about taking weight on still stands, but I'd say that our performance in offshore conditions is rather good and what is truly remarkable is how staid and steady she feels in very rough conditions and winds well over 35kn.
     
  14. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    Yesterday’s 7 Vaka Moana canoes were provided by a charity organisation. Another 6 Vaka Motu were created by another charity organisations for interisland cargo and transport. The boats are Okeanos Marshall Islands, Okeanos Vanuatu, Okeanos Ambassador (previously known as Okeanos Marianas now residing in Yap), Okeanos Wa’a Qab (Yap), Okeanos Pohnpei and Okeanos Palau.

    The Vaka Motu are 50 x 20 foot weighing 20,100 lbs and capable of carrying 6,700 lbs. The single 50 foot mast carries 615 square foot of sail area. The length to beam is about 10 to 1. The hull draft is 2.2 foot with a draft of 6.2 foot over the daggerboards. There are several engine options from full electric to Hybrid systems. The option on the boat here is two Hybrid systems with 20hp Perkins engines that run on traditional diesel or coconut oil – as well as electric drives. These weigh 260kg (130kg per side) – conventional lead-acid batteries providing the same amount of power would weigh six times as much. They provide 300 amp-hours at 48 volts or 1,200 amp-hours at 12 volts. Each of the four solar panels delivers 365-watts – around 700-watts per bank of batteries. Motoring speed is about 6 knots.

    The sailing performance with her more traditional ‘claw’ rig – with an ‘upside-down’ triangular sail. Average sailing speed is 7-8 knots, and the best apparent wind angle is between 55 degrees and 60 degrees. 4 crew are required to sail the boat as it is primarily a sailing vessel.

    The accommodation is both a small on deck hut with 5 foot headroom for up to 8 passengers and a navigation area. The hulls contain bunks, toilet facilities, galley, engine system and a 60 litre per hour water maker. The water maker: “It’s not so much for the crew,” says Peia, “but rather to supplement water supplies for the communities in the islands in a disaster-relief scenario”.

    The traditional Polynesian design is built by NZ Lloyd Stevenson Boatbuilders. The hulls are female moulded with epoxy, e-glass and foam core. The hulls are held together with heavy, wooden cross-beams tied by traditional lashing. The lashings – as well as the standing rigging, is a modern material (Vectran). The massive steering oar (called a ‘hoi’) with its intricately-carved graphic. Built from solid timber, it weighs a lot. But because it pivots delicately on a single knuckle (made from kwila), and because the ‘blade’ is buoyant, steering the Vaka Motu, is supposedly very easy.

    Again very interesting boats designed for a specific function of cargo and transportation needs of remote Pacific islands. Good vessels. The jpegs give the idea.
     

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  15. Iridian
    Joined: Jan 2020
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    Location: MD

    Iridian Junior Member

    Can't understand the sail plan. Looks very poor for basically anything.
     
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