low energy design

[treeman]

I'm a designer and builder of many things (homes, offices, landscapes, etc.), environmentalist and avid deep sea fisherman. My son and I love to fish in the Gulf of Mexico but feel VERY bad about the amount of fossil fuel it takes to get there. When I was a kid I remember a newspaper story about a hull design that was a slow but seaworthy and low power consumption vessel. I'd love to have something in the range of boats that I've had before (cruisers in a 27-32' range), no particular need for speed, enough beam to be comfortable and, above all, safe for 8-10' seas. Any ideas or insights?

[kach22i]

I think there are two design conditions and one very large condition of nature to contend with that of sea state.

Breakdown.......................

1. Below hump

2. Above hump speed

3. Out run weather

4. Plow though the weather.

Sounds like you are seeking a below hump speed and plow though the rough weather design.

This is not very sexy nor efficient time wise to be caught out at sea in a small craft for days and perhaps sucked out to sea unable to power out.

It seems to me that this is a personal exploration of thought and not something expected or sought out to have mass marketing appeal, not always a bad thing.

Sounds almost like a lifeboat or rescue pod to me.

[treeman]

Well put, kach. I'm much more interested in the experience of being at sea on my own moral and ethical terms. Outrunning the weather, while desireable in one sense, denies the fact that you're at sea and that it is a wild and unpredictable place. It also comes at a cost in efficiency and pollutes the very "nature" that we go out to enjoy. I spent much of my youth on fishing vessels that couldn't hit 10 knots with a light load and a strong tail wind. Not a marketable type of trip but not a bad one.

[kach22i]

Originally Posted by treeman

I spent much of my youth on fishing vessels that couldn't hit 10 knots with a light load and a strong tail wind. Not a marketable type of trip but not a bad one.

Interesting, would it be fair to say you are looking into and researching a more modern or "green" version of a traditional fishing vessel?

Solar/turbine/wind/sails and other means to be considered?

This link has a few interesting concepts.

http://blogs.business2.com/waterlog/...sel/index.html

[Chris Ostlind]

Originally Posted by treeman

I'm a designer and builder of many things (homes, offices, landscapes, etc.), environmentalist and avid deep sea fisherman. My son and I love to fish in the Gulf of Mexico but feel VERY bad about the amount of fossil fuel it takes to get there. When I was a kid I remember a newspaper story about a hull design that was a slow but seaworthy and low power consumption vessel. I'd love to have something in the range of boats that I've had before (cruisers in a 27-32' range), no particular need for speed, enough beam to be comfortable and, above all, safe for 8-10' seas. Any ideas or insights?

This sounds like a job for a cat with a pair of long skinny hulls, Treeman.

Let's just assume that you do not wish to get up on plane (mucho fuel and pretty big engine in the length of vessel you describe) There is no better solution for displacement or semi-displacement efficiency than with skinny hulls.

a trimaran solution with amas that only interact with the water surface during heavier seas and while turning is a pretty good solution. It can also give you a large amount of deck space. It can provide you with a solid fishing platform, as well.

A catamaran gives you both; a large, comfortable area from which to do any of your interests and it also provides a terrific, fuel efficient hull design for semi-displacement speeds while still giving outstanding fuel economy. Cats also have a comfortable motion in a seaway.

I'd go with the cat. A modest bridgedeck structure designed to get you out of the elements, while keeping the aerodynamic form to a minimum. You can enjoy the fact that if you equip the vessel with a pair of modern, quiet, four stroke outboards, you will get great fuel mileage. There is even room in this type of boat for a pair of smallish diesel engines that can be modified to run on bio-diesel fuel sources for enhanced value relative to the environment, though you will have to be clever when you refuel the boat between uses.

I do not think that battery/electric motor propulsion is at the point where it could be used as the sole source of drive for an offshore capable design that can handle variable weather in a near shore environment. It still has a way to go, but it is getting closer to a reality each year.

Chris Ostlind

[kach22i]

Originally Posted by Chris Ostlind

This sounds like a job for a cat with a pair of long skinny hulls

Yep, most of the boats in the link I gave earlier are Cats and Tri's.

Good suggestion.

How do you "right" a Cat or Tri in heavy seas should it be flipped over though?

[Chris Ostlind]

Originally Posted by kach22i

How do you "right" a Cat or Tri in heavy seas should it be flipped over though?

The same way you raise a sunken monohull.... you get help. ;-) But at least you are still floating.

If the conditions are bad enough to get a boat this size tossed, then all boats out in the same conditions are in trouble as well and should have been long ago motored off to the friendly confines of more quiet waters.

[Guest20100203]

Off the top of my head I can come up with a dozen or so designs that fit that bill. Efficiency is a relative term. How much fuel per hour usage could you live with, for an average day's outing? Sailing doesn't use fuel, or at least very little.

Safety in 8 to 10 footers is typically the responsibility of the skipper, assuming a reasonable design. A wise one will use the throttle to suit conditions. A foolish one will be read about in the following day's papers.

[Geoh]

Everyone says they want the economical, safeer, full displ hulls but they dont really want to go that slow.... Homer Hughes designed and built the Allweatherboat ...In the 80s and 90s could only sell 32 of them in 20 years of production... the molds and whole boat building setup still in place in Fernwood WA. if anyone really interested... http://www.allweatherboats.com/

George Hood

[fcfc]

Originally Posted by Geoh

Everyone says they want the economical, safeer, full displ hulls but they dont really want to go that slow.... Homer Hughes designed and built the Allweatherboat ...In the 80s and 90s could only sell 32 of them in 20 years of production... the molds and whole boat building setup still in place in Fernwood WA. if anyone really interested... http://www.allweatherboats.com/

George Hood

I can only confirm.

See this other post from a naval architect :
http://boatdesign.net/forums/showthread.php?p=9339

Originally Posted by Tad

....
A few years back I was lucky enough to have a couple of guys come along who wanted to build a beautiful boat that was really economical. We did it, the Memory 38 resulted, full displacement hull, she cruises at 7.5 knots with a 50 HP engine and uses about .75 gph. Hundreds of folks have been aboard her, and admired her, but no one has bought one. Painful lesson.
...
Tad.

[kach22i]

They are very similar looking. Seems to me this is the popular look of today I see in Popular Mechanics.

[treeman]

That's brilliant stuff guys. I was thinking catamaran. I should have mentioned that stability at anchor or drift was important to the fishing process (although I have a soft spot for a classic trawler). Tri would be cool, too, but I guess a twin engine cat would have a bit more maneuverability. It would be nice and green to go electric but the balance between power storage and sinking would be a crap shoot! I thought about hybrid diesel/electric with a solar component but that wouldn't achieve the same big efficiencies that a land vehicle would because you don't do all of that revv'ing and constant speed changing. Thanks for the great input and keep those suggestions coming!

[tom28571]

Chris, You said it in a roundabout way but the cat you propose can easily run at two to three times the hull speed of a similar length displaceemt monohull. That puts speeds in the upper teens in reach while still getting good fuel mileage.

[Munter]

The low power offshore cat sounds like a cool concept. Diesels running on biofuel should be enough to ease your environmental conscience. It should also reduce your running costs to help pay for the additional design & engineering work required.
With low total power I'm guessing that windage could become a significant issue?
There's something similar in Pittwater though it looks more leisure oriented than a true offshore fishing boat.

http://www.modernboating.com.au/boat...Innovations-14

Not sure how its powered but the article will probably say.

Cheers,
Munter.

[Pericles]

Here is a hull design that works. http://www.alnmaritec.co.uk/downloads/Wave%20Angler.pdf

The vessel lines at the bottom of the article look like someone took a circular saw and divided the hull longitudinally and separated it into 2 pontoons, before completing the build.

Munter,

Thanks for the link.

Regards,

Pericles