designing for legal size/weight/crew/captaining limits

Discussion in 'Boat Design' started by big_dreamin, Sep 19, 2016.

  1. fcfc
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    fcfc Senior Member

    On chartering and dual use boats ...

    Boats made for profitable charting may be different as owner boats. Freighters trucks and buses don't look like individual cars.

    For chartering, a catamaran sailboat 45ft, with 4 double cabin, with ultra big genset, with reefer, aircon, generous water maker , a crew of 1 / 2 may be the best way to make some money.
    The cabins are affordable (around 2000$ a week). It is way easier to fill 4 cabins @ 2000$ a week, than to fill 6 cabins @ 6000$ each. (a 60-80 ft catamaran).

    For cooking for 8 @ 1000$ each, a trained waitress / hostess / deckhand / scuba monitor / captain wife can suit.

    Cooking for 12 @ 3000$ need a professional cook.


    Now, 4 double cabins with 4 toilet/shower on a 45ft, or 6 double cabins with 6 toilets/shower on a 63 ft are clearly NOT owner boats. Way too cramed.
     
  2. fcfc
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    fcfc Senior Member

    Of rules limits, the 24m CE limit:

    You can find :
    http://pdf.nauticexpo.fr/pdf-en/cantieri-navali-san-lorenzo/sd-92/23556-36271.html#open (Sanlorenzo SD92)
    http://azimutyachts.me/boat-spec-1267-1.pdf (Azimut 95 rph)
    http://seanetco.com/pdf/Brochure-DELFINO.pdf (Benetti Delfino 93)
    http://www.ferretti-yachts.com/en-us/range/gallery.aspx?IdBr=1&IdBm=36&IdM=60&g=EXT (Ferretti 960)

    Yet another one ...
    http://www.canados.com/index.php/canados/canados-969-coliseum (Canados 969)

    All are boats very similar in size and layout, except powering and speed, made by known boat manufacturers. So there may be some significant market niche. At least for FIVE manufacturers to go.

    All are around 92-96 feet overall length, but have Hull Length just one inch smaller than the CE Limit of 24m. I guess there is a big theoretically removable stem at the front, just before the FP.

    And I guess the 5 cabin version all have (1 big owner cabin on deck, 4 smaller below) are just a way to do occasional chartering. The chartering will not pay the boat, or even its operational costs. It will just help the owner to reduce some operational costs.
     
    Last edited: Oct 25, 2016
  3. big_dreamin
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    big_dreamin Junior Member

    My understanding was "except for narrow length to beam ratios". I'll admit being a fan of what i'm reading here http://www.multihulldesigns.com/pdf/powercatslt.pdf about displacement cats.

    Right, I think I understand that part. I'm just always curious what the optimized designs are - you can always add weight to panels/members without increasing strength for instance. There is also a minimalist design which you can't take anything away from anymore. I see alot of catamaran hulls that have poorly optimized shapes, for instance bulbous intrusions barely above the waterline that will drag on even the slightest waves ruining efficiency. I'm no naval engineer yet even I can see that's dumb.


    I'm aware of that, but my plan is to try avoid most marina issues. By the time i'd have the 79 footer i'm hoping to have my own little piece of beach and dock on the Great Lakes to start with. In the future when I take it to another country long term i'd hope to have the same there. When traveling outside this i'd hope to mostly be at anchor away from it all only dropping in to refuel/get food and such.

    Right I think i'm still with you. What exact tradeoff of "more decks" vs "bigger boat" is best for me i'm not sure yet. I would spend alot of time with spreadsheets trying to make some guesses and projections though. For stability though instead of more weight what about a larger platform? In general I like the idea of just going to sea with a bigger boat as the best solution to higher seas anyways, i'd rather have a 120 footer even if it was only a single deck and the bridgedeck covered only half the total footprint to get the longest narrowest hulls possible with the lowest weight and the best seakeeping for the money. At least until it creates diminishing returns or other problems though.


    No, but a bus and RV look pretty similar and that's more what i'm interested in doing. I helped convert a schoolbus into an RV when I was in high school that also could haul lots of stuff... especially when more volume than weight it was just as effective as a box truck. If the rear door could have been made wide and fully opening it would have been just as convenient too.

    I'm also not against planning for future reconstruction or modifications, trying to make something modular or DEconstructable/changeable in the future, like making for instance 8 smaller rental cabins convert into 3 luxury family cabins and one 'family room on the water'. One thing I like about the big flat bridgedeck of a cat is that it's an open space like an office building and not that hard to change it to do different things IF you plan for that. So long as those things are mostly different usages of space (private yacht, passenger charter, physically large but light cargo) and not heavy low profit stuff like iron ore I mean.

    I'm aware that i'm exploring a number of ideas and possibilities here, but it will be years before I even lay a keel for anything so i'm not in a rush. I'm just feeling out a multitude of possible futures, while exploring which criteria really are the most important to me.
     
  4. big_dreamin
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    big_dreamin Junior Member

    Thanks for some of those examples, I wasn't aware the boat could exceed 78 feet at all/didn't realize it was just waterline length.

    I'll try and share some of my thinking so you can help me narrow down the holes. I'm aware there's some points where my mouth is probably outrunning my brain where I didn't quite think far enough through things so far. :)

    Apparently average cruise ship cabins are around 140 square feet for double occupancy, an average hotel room in the US is around 325 square feet though can readily be had with two fullsize beds in that space for quad occupancy. So I assumed I was looking at around 900-1000 square feet of space for six double occupancy cabins for 12 passengers. Not including a couple of closets for crew. (if i'm getting paid well I can sleep in a closet for a week, knowing that it's temporary and not full time)

    On 78 feet of length and say 24 feet of width like i'd considered, that doesn't even require the bridgedeck to cover the full length of the hulls/it's about 38-42 feet of length on the 24 foot width or so not including hall space.

    I may be making a mistake but i'm not sure where it is. :p
     
  5. fcfc
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    fcfc Senior Member

    No. Waterline length and displacement drive nearly all. All the remaining parameters count for less than 20%. See the book "Principle of yacht design Larsson Eliasson.


    Another boat : http://www.berthon.co.uk/yacht-for-sale/nigel-irens-63-motor-yacht-molly-ban.pdf

    Nearly same length, same speed as the "basic" boat in my previous post. Half the displacement. Guess what : it needs half the power = One single 300 hp engine...


    But an EXTREMELY important point you forgot : Nearly ANY boat GAINS in efficiency by going SLOWER...

    See : http://www.nordhavn.com/models/64/specs/

    This 83 tonnes boat at 8.4 kts has a similar fuel burn/disatnce efficiency as the 34 tonnes catamaran Lagoon 63 MY at 12 kts.
    And at 6.4, it is on par with the catamaran at 10.5 kts.

    And people with low bucks, who would theoretically be interested by high efficiency boats, just don't buy high tech boats.
    They buy basic steel boxes like http://www.dieselducks.com/55build-6.html or http://buildingkoloa.blogspot.fr/se...00-08:00&max-results=33&start=8&by-date=false

    And go plain slow to gain in efficiency.

    If you put one week more to cross the Atlantic at 6-8 knots instead of 9-12 knots to keep the same fuel burn, what is the deal if you save some hundred of thousands $ in the building process ???
     
  6. fcfc
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    fcfc Senior Member

    Back to the 90-95 ft boats.

    Four similar, still below the 24m CE limit
    https://www.princessyachts.com/media/8688/princess-30m_boat-international.pdf (written in the text)
    http://www.sunseeker.com/yacht/95-yacht/download-brochure (written here http://www.poweryachtblog.com/2016/09/new-model-sunseeker-95-yacht.html)

    Forgot
    http://www.customline-yacht.com/en-us/thefleet/external.aspx?IdBr=8&IdBm=118&IdM=187&g=EXT
    and
    http://www.sanlorenzoyacht.com/en-us/Home/Yachts/SL/SL96

    In fact, the 3 top Italian builders (Benetti-azimut, Sanlorenzo,Ferretti) have each 2 variants one semidisplacement, and on planning.

    And slightly different, but still within the 24m CE limit, and 5 cabins the beneteau brand
    http://www.montecarloyachts.it/en/mcy86




    Another 2, same flavour although slightly bigger (longer lwl and not CE compatible ) :
    http://us.horizonyacht.com/Overview.aspx?Cond=6DCBA2C7-D838-4C84-BFCA-D9E1F588D580
    http://www.gulfcraftinc.com/majesty-101


    So you have surprisingly close products from nearly all major yacht manufacturers. That makes a very crowded market niche.

    And despite such strong competition, the price range of theses boats is still 7-9 MILLIONS Euros.

    And charter price for ONE week is in the range of 50000 to 70000 €. For 10 passengers, with a crew of 4.
     
  7. big_dreamin
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    big_dreamin Junior Member

    Thanks for the specific book suggestion and i'll add it to the reading queue. Though i'll admit saying hmm to a degree... sounds like the guy I linked is designing boats with greater efficiency and speed possible in the monohull world, unless i'm misunderstanding something?

    I mean it makes perfect sense to me that shape is all important in drag - that some 80 foot long 4 foot wide cat hulls should have less drag than 40 foot long 8 foot wide cat hulls especially if you chose to go 15 knots instead of 8 knots. Different shapes produce different wakes, canoes are long and narrow for this reason, wakes itself are just a bunching up of water in front - it's similar to how area-ruled fighter jet aerodynamics were designed in the early supersonic fighters which i'm familiar with/there the air bunches up and can't get out of it's own way too so it never achieves laminar flow so the shape is made "long and narrow". Water is just way denser so it happens at far slower speeds - reduce the wake and you reduce the drag.

    I'm positive somewhere I have a book reference from the UK navy or somesuch on higher speed hulls talking about beam to length ratios beyond 8:1 using different numbers to calculate waterline speeds and efficiency at speed... not necessarily those done with relatively short fat hulls but truly truly long and narrow ones.


    I assume down to some minimum speed like that of a barge below which it shouldn't matter? There's also the issue that if there's a 4 knot current against where you want to go the 8 knot monohull is making almost no progress at all whereas at least the 15 knot cat is only slowed a bit.


    I'll give you that much, I just think there's alot of other good reasons to have higher performance potential even if you choose to run slower for max range at other times. More flexibility in avoiding unexpected storms being one. (i'm also aware a counterpoint is that it takes fuel burn to make a big difference in going well out of the way for a storm and a strong stout monohull wont break apart as readily if caught in one - there's always two arguments in every case)


    PS - was my math off calculating cabin space for up to 12 people on a catamaran btw? :p Or did I forget to include something important?
     
    Last edited: Oct 25, 2016
  8. TANSL
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    TANSL Senior Member

    Have you had in mind all the spaces that are associated with cabins ? : toilets (toilet in each cabin ???), kitchen, laundry, loung, dining room, linen store, central air conditioning units, ..... .., hallways, meeting areas to abandon ship, ......
     
  9. fcfc
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    fcfc Senior Member

    Yes. That guy does 28 kts on the 61 ft catamaran only because the cat weight 18000lbs empty. And it needs 900 hp for that.

    900hp burn 50 gph. This is 500 gals for 10 hours full power. It is a catamaran that need to go to the gas station EVERY day. And I am not sure this boat is strong enough to sustain 3 continuous days of storm without breaking.

    On the photo, it has NO forward deck. And probably cannot have one. Too heavy, too much stress on the structure. The hulls are not liveable. The only "liveable" area is the 20 ft * 20 ft roof. With the express condition of not putting any weight inside...

    Now, if you want to cross Atlantic at 15-16, and top at 28, it can be done.
    https://cmn-group.com/products-and-services/military-vessels/tsm/ocean-eagle-43/
    But it is a 75 tons tri, 140 ft length, built in carbon infusion, oven cured. With 4 * 500hp engine (total 2000 hp) Price is counted in TENS OF MILLIONS euros.
     
  10. big_dreamin
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    big_dreamin Junior Member

    My question though is whether any other monohull will go 28 knots on 900hp at 18k displacement. My assumption was not?

    I'm aware that speed costs money but there are also benefits for that - not everything can spend a few weeks at sea, perishables and such. The fact that one boat at 16 knots can do twice the # of loads that a boat at 8 knots can. Others pay for fast ferries for convenience. So my specific cargo interest was more in the "people that would pay for faster speed" of potentially larger volume but lesser weight. They don't HAVE to pay for faster speed, but the opportunity is there, whereas with most monohulls of smaller size it is not.

    Whether or not that market will pay for itself I don't yet know, but that was the target, since big slow heavy monohull displacement craft pretty much have everything else locked down for all global shipping options on any route worth having via sheer economies of scale. I can't just do what other people already do so it was my decision to try and focus the research here, wrong or right.


    Different horses for different courses. Someone else called not letting such a cat end up in a storm proper seamanship just a few posts up I think. :^) I was still trying to explore more of a catamaran of that style because unless the designer was lying, it seemed to be genuinely "more efficient at speed" say a 12-18 knot running, quite possibly without an appreciable increase of gallons per mile. Yes more gallons per hour but if youre moving twice as fast, twice the gph is a win not a loss, 3x the gph probably tolerable. 6-8x the gph is probably the loss like it would probably be in planing vessels.

    There's three possible issues at play - speed, efficiency, and seakeeping. I'm not claiming i'm an expert, it's just the designer above is not the only such cat i've seen designed, just the only whose link I had handy, and i'll agree they are uncommon. "Normal" cats have fat hulls (poor beam to length), low bridgedeck and transoms getting caught up on all the waves, often poor hull shapes (not vertical, designed for living space with bulbous protrusions instead of a flat linear hullform designed for best hydrodynamic efficiency), etc etc. I fully get why 'normal' cats aren't much faster or more efficient than a monohull, i'm just not sure how many people have fully researched those with 8:1 or 12:1 or even greater length to beam ratios.

    I picked up that Principles of Yacht Design book from Eliasson and while it's interesting reading, i'm not sure whether or not it covers long narrow hull catamarans. I'm pretty sure at their intended 40 foot design length a catamaran alternative is not going to be a great performer without going expensive superlight carbon fiber - but the sailboats that ARE like that seem to get incredible speed and effective efficiency of turning a given sailplan into fast forward movement. I'm wanting to design a powerboat the way they design efficient sailboats is the only thing i'm doing at all here. If I can get a concession that sticking power to a modern sailing cat hull should give speeds and efficiencies beyond that normal fathulled cats are going to see. Since then it's a separate discussion of whether such a cat can be designed at certain sizes without ubermaterials instead of there's no benefit to even trying.


    I'm aware of your gripes that that cat design I linked is not designed for heavy weight - I don't think I implied it would work "built like most boats". It's not designed to bash through storms, have four decks on top, or carry iron ore. It's a design that ONLY can work if you stay LIGHT LIGHT LIGHT. I'm only seeking a concession on this one point - that a light cat like this isn't forging/lying about what I thought were pretty good numbers for speed and efficiency-at-speed. I do not claim that those compromises are good or bad, just that they at least have the potential to be viable. I'd like to know what that 900hp cat gets at a 12-18 knot cruise instead of 28knot full power, personally since that's my real goal.

    I've been fascinated with boats of a design like this ever since I met someone who had designed something like it and was reporting efficiency and performance I would have considered impossible, and I don't think they were just fish tales. It was all about keeping it super light in design with super long narrow hulls.


    I'd be content at 12-18 knots (usually 12 but able to do some passages a little faster) in something around an 80 foot catamaran (with a bridgedeck smaller than the max dimensions) and wondering how low the fuel burn per mile could be by keeping weight as low as feasible and optimizing the hullform to minimize drag, waves and wakes before all else. More often in 'faster than most monohull' service might use the 18 knot speed for shorter runs more often.
     
    Last edited: Oct 26, 2016
  11. big_dreamin
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    big_dreamin Junior Member

    Yes, but some of those things depend a little more on what kind of voyage it is. A weeks long "nothing to do but spend time aboard" is going to need more recreational areas, whereas beachhopping every day and doing nature oriented hiking/ mountain climbs/ optional camping might have alot of the food prepared ashore (dinner and breakfast, so only lunch to be provided on boat, and might be prepared in morning and just kept warm til serving), shorter journeys (4-7 days of beachhopping) I can't see laundry as being a must-have on board for my plans so far, if it was 3 weeks obviously it would be. Being a catamaran I was thinking less on the hallways and more just having the rooms open directly to the deck, etc.

    I'm not claiming everything is locked down at this point, just that I was exploring many options, some needing more space than others, and that I didn't think a 12 pack on a 78 foot catamaran impossible - just... tricky. That said if it's just not feasible then a little more length brings it into line, or knock a couple cabins off since 4 or 5 double cabins is still more profitable than 3 at a time. By playing with the Simplified Hull Measurement pdf getting it over 100 GRT to allow a 12 pack license (even with less passengers) is just enclosing a little more space intentionally - or designing it to be lengthened to enclose that in the future. (ie design for 3 dual occupancy cabins at first later upgrade to 4-5, remeasure the vessel, and upgrade the captain)
     
  12. fcfc
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    fcfc Senior Member

    The problem is not an hydrodynamic problem. It is a manufacturing cost / stability problem. At 18k for 61 length with ordinary materials , you simply do not have enough material to build wide enough to be stable strong enough monohull. (except if you go to aerospace technique. this is the weight length of racing open 60 sailboat, beam around 17-20 ft)

    Once you have enough displacement to build a decent monohull (see in previous post the molly ban at 32k), you have very little powering gain to use a catamaran design. In fact, you even have penalty at low speed, because the catamaran will have more wetted surface compared to the monohull.
     
  13. fcfc
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    fcfc Senior Member

    There is a huge amount of questions to be answered way before speaking of monohulls or catamarans.

    You speak of 12 passengers. For 3 month operation, you need to attract roughly 150 people and have them pay you.

    If you are in a non or few tourists zone, how you will make it ???

    If you are in a tourist zone, it may be done. But is likely to already have some kind of regulation.

    Is landing people allowed (say bird zone) ?
    Is motoring/genset running allowed (pollution, noise) ?
    Is beaching or anchoring allowed (ground destruction) ?
    Is water discharge allowed (grey water/ black water) (pollution) ?
    Is BBQ allowed on land (fire hazard) ?
    Is picnic allowed on land (waste management) ?
    What about licence/entry fees/limited access for local operators for that zone ?
    What about competitors ?


    Now what your customers will pay, and what they (I mean they, not what you think) would expect for that price ?
    Note that your passengers will likely include the price to reach your start point in their total holidays costs and will just see it (travel cost + boat chartering) as a whole holyday cost for a week.

    A shower a day for 12 + 4 crew = 16*15 near 250 gals or water a day. Were it come from, were it is discharged. How it is heated, with what energy ? If you have 6 passengers heads, just guess 4 showers at the same time the morning.

    Now for food : fresh food, canned food. If fresh food, were it will be stored ? Fridge size for 12 people eating 2 meals a day + breakfast. Reefer for ice cubes, ice cream ? How often you plan refilling fridge and or reefer ?

    Cooking : hot meal / cold meal ? How do you plan to heat food for 12 ? Oven size / energy ?
    Prepared food / ready to eat food ? What size of kitchen/galley ? What appliances ? Dishwasher ?


    Going to land : tender size ? 12 at once / 6 at once / 4. By 4 (in fact 5 = 4 passenger + 1 crew), you need 3 travels. If the tender travel last 7 minutes, the last passengers will arrive nearly half an hour after the first passengers. How many tenders ?

    Climate control ? heating / air conditioned.

    What about rainy days ? entertainment, clothes drying ?
     
  14. fcfc
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    fcfc Senior Member

    FYI, a lagoon 63MY is around 2M€ base, and probably around 2.5M€ fully equipped for chartering.

    And is around 30 000 - 35 000€ a week :
    http://ocean-yacht-charter.com/details/luxury-motor-yachts/charter-lagoon-630-my-croatia-936 (10 passengers with a crew of 2)


    Another power cat :
    http://www.powerandmotoryacht.com/sunreef-yachts/sunreef_70?tab=test

    Price tag 4.4M$.

    Chartering price:
    http://ocean-yacht-charter.com/deta...ts/clouds-sunreef-power-catamaran-croatia-954
    35 000-43 000€ a week

    Note : given the charter price per DAY, around 5000-7000€ (a DAY), adding (or saving) 200 gallons of fuel a DAY will not significantly change the price ...


    One somewhat cheaper : (But still 1.2 M€)
    http://www.balta.fr/catabob.html
    http://www.balta.fr/CATABOB/essai version anglaise mm.pdf

    In this video, https://youtu.be/FKZigQaGBwQ?t=51s you see what are the "cabins" located in the hull. The problem will be to make the passengers pay for this comfort.
    And here you will see the boat go upwind https://youtu.be/FKZigQaGBwQ?t=3m37s Light boats will suffer in these conditions. Whether monohull or multihull.

    Another video http://www.balta.fr/CATABOB/enmer/Visite du bateau media ETOILE.mp4 Check boat handling at the beginning.

    And this boat still burn around 4gph at 10 knots. On par with the Lagoon 630, or other monohulls of same displacement. No magic nowhere.
     
    Last edited: Oct 26, 2016

  15. big_dreamin
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    big_dreamin Junior Member

    EDIT: If you just read this already, I expanded instead of adding another post to the end since I still don't have any responses.

    Sorry it's been about five weeks, been working in the oilfields so haven't had internet for awhile. Also wanted some time to think about how to better define my thoughts, realizing if there's a miscommunication it's probably my fault since i'm the new guy here. fcfc especially poses alot of good questions - it's not that I haven't considered questions like this before, he clearly knows what he's talking about, i'm just trying to figure out how to better clarify what is in my head. It's also really early in what will be an iterative process as i'm still years from a more defined specific plan though. So let me try again from a new angle:

    My biggest #1 goal is that i'm trying to have the most deck space for the displacement. To me this means catamaran or at least another multihulled vessel. The only reason I talk of 6pack or 12pack licenses for what would normally be too short is because it might work on a wide cat. (and even if not, coming in just under, like 5 passengers on a shorter or 9-10 on a longer one)

    My #2 goal is that I would like to have a design speed of say around 12 to 18 knots. Yes i'm aware going slower means saving more fuel - but my design goal is 12 to 18 knots. At 7 knots i'll agree it doesnt matter what shape the hull is, but as near as I can it does matter at 12-18 and long and narrow rules the day. Even if it comes down to just going against a current, 7 knots in a trawler can turn into 3 knots in some places against a 4 knot current to the point that I might use more fuel in the trawler than I would at a faster speed I think.

    #3 goal is to have the most boat for the money NOT the most boat within a given length. My preference is to build longer, wider, lighter, simpler, single deck with only part of it even enclosed but the whole boat scaled up to the size needed for 6/12 pack. Cat hulls may well be longer than the deck itself because length seems to increase efficiency and let you run narrower hulls. I can't compare against others multimillion dollar yachts because i'm not going to build that. I've known of others who have built boats of a design like i'm suggesting. I'm not worried about docking or marina fees in this design because they wont be needed if other parts of the plan come together. I don't know whether it will charter for similar or much less or not at all but that was never the top goal anyways, usability was.


    What i'm sort of thinking in my mind right now trying to design around simplified tonnage rules would be 78 feet long, maybe 18-20 foot beam or so, having the bridgedeck high enough up to be above the sea state I expect to regularily run in (and not have waves slamming the deck - which further means it doesn't have to be built for the constant abuse either, it's also extra drag when youre plowing waves instead of slicing through them) and trying to minimize the weight and thus displacement. I know of someone who built a boat very similar to this weighing under 30,000lbs with apparently excellent seakeeping even in 4-6 foot waves. EDIT: He has if I remember around 300hp diesel and reported getting something like 2.5mpg at 12 knots because he was able to keep the weight (and thus displacement) down, so I figured if he already did it why can't I? There's a note of frustration of people saying "this wont work" when I know of multiple boats doing this for years, even if I don't have pictures or personal contact info to show everyone since I first learned of this design 15 years ago and many things have since expired/websites gone/etc. Lightweight high bridgedeck power cats just are not a popular thing yet and I don't understand why.

    EDIT: Decided to expand all of this a bit.


    Trying to bring further clarity to the issue: For potential business purposes, I am not trying to "directly" compete with anyone. Quoting that someone else spent so many millions for a boat, that charter is so many tens of thousands a week, that they are using so many gallons per mile at a given speed - I am not trying to directly compete with any of that. Anything i'll be doing is probably seeking a niche that I have an advantage and that they are not as well suited for.

    For instance if they are all trawling at 7 knots, and I build a 12-18 knot boat (like the guy I mentioned above did), I might have an opportunity for LIGHTWEIGHT but larger volume cargo since i'll use less fuel to move it. Or I might have an opportunity for more perishable or faster priority cargo. Or if i'm using it as a fishing boat, I might be able to go to a further off fishing ground than them which for high dollar fish like some of the bluefin and yellowfin Atlantic tuna going around pays for itself surprisingly well as long as fuel costs don't get completely out of line like they would with a monohull trying to do that.

    I wont be able to compete "luxury for luxury" with someone who normally has it in their mind they are chartering whatever boat for wedding guests or for some week long family adventure or whatever. Yet by having less money in the boat, and more fuel efficiency for a given level of performance, I may have a niche to find people who need more boat with less flash and will pay half the going charter rate for giving up the fancier luxury.

    Which of these am I going to do? I dont know yet. Any of them. All of them maybe. They're all niche possibilities - lightweight high volume or/and perishable cargo (on uncommon/less served routes), certain fishing applications (a very wide large deck boat that's more efficient/less displacement than other monohulls used for tuna fishing means I could put more rods'n'reels out), possible charter use by 6-12 guests, or just straight up private yacht usage if all else fails. The basic boat design has to come and work first - and i'd like to leave the superstructure and other add-ons up in the air or even some kind of modular/changeable design in case I try some niche and it doesn't work well so I refit and try something else.
     
    Last edited: Dec 4, 2016
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