Optimum Ocean Voyager

[marshmat]

Trailerable limits beam to 8'6", an oversize load permit over 10' is darn near impossible to get on a regular basis.
Trailerable with a standard licence (ie. not a trucker's licence) usually limits weight to 4.6 tonnes including trailer.
It'll be tricky to fit all that into a trailerable boat. Radical idea- how about folding amas? Trimaran on the water, but hinge the amas up to trailer, much like some Navy fighters do with their wings. You'd then be able to have deck space on top of the ama struts for guests etc, with cabin space inside. (Could also use them like the VO70s use their keel if you capsize- release the amas, winch one around, and you're right side up again.) But you lose the narrow-canal ability of a mono. And fuel for 2400 n.mi. weighs a lot, especially when you're on the trailer. I'm thinking narrow and long, for efficiency, and to be able to fit under highway bridges. Just some thoughts....

[Guillermo]

Originally Posted by FAST FRED

...Having seen all the garbage usually considered for EMERGENCY PROPULSION, rusted "wing " engines , belt & chain drives , hyd nightmares , the usual long list, the use of minimal sails seem to make much more sense...

I agree. Very much in the line of Chuck Payne's SteadySailer: http://www.chuckpaine.com/zsteadysailer.html

[yacht371]

This small powercat, built in Poland, can do most of what you want, is light and trailerable.

I plan to take one across the Atlantic in 2006, but that will require 150 gallons extra fuel beyond the boats standard 50 gallons. It can get 8 NMPG at 15 knots.

www.motorcat.com
www.aviadesign.com

[Guillermo]

Originally Posted by yacht371

This small powercat, built in Poland, can do most of what you want, is light and trailerable....

I've visited the pages and find the Motorcat an interesting design. But I have some doubts about the statement that 20 M height, 100 m length waves are necessary to turn upside down the boat. In my humble opinion most probably a 4-5 m steep or breaking wave, as the ones sometimes encountered close to land when bad weather, may be enough.

Crossing an ocean is not only a matter of range or speed, but also of seaworthiness, seamanship and survivalability. I wish you good luck.

[FAST FRED]

" It can get 8 NMPG at 15 knots."

This is a fuel burn of about two gallons an hour total.

With diesels the usual rule of thumb would be 16 to 22 hp comes out of a gallon. 16 for a 1930's designed Dteroit Diesel , and 22 for the latest turboed high pressure rail electronic injected units.44hp (at best) isnt much.

How was this fantastic fuel milage claim measured?

FAST FRED (Dreaming of a 5-nmpg cruiser)

[yacht371]

Hi Fred,

The fuel burn statistics are based on the single diesel version. Outboards, even 4-strokes use a lot more. However the boat does do 21 knots on 60 HP, 15 knots takes about 35 HP. This is from actual sea trial of the prototype fitted with fuel flow meters and twin Yamaha 60 HP 4-strokes. We were over propped and could not reach full revs so the engines were only putting out about half power based on fuel burn rates.


The diesel version is under construction and we will test it thoroughly and post results.

In the meantime the projections are indeed computer generated, but I have done many of these and have never been "off" by more than 10% or so.

The actual figures may be found at www.aviadesign.com.

By the way, ocean crossing in a small boat like this is not recommended, even though possible. It falls into the "stunt" cataegory, although not quite so much as sailboards, and rowboats which have done the Atlantic crossing many times.

That said, I'm designing a larger Motorcat which will have long range cruising ability right out of the box. But it won't be trailerable...

[yacht371]

I already own a boat which is more fuel efficient than I'm claiming for the MC27. It is a Hanse 371 sailboat fitted with a 28HP Volvo saildrive. It can cruise at 6.5 knots under power using 2 liters of fuel per hour. That is about 13 NM per gallon and the boat weighs about 8 tons, 3 times the weight of the MC27 and with more windage due to the mast and rigging.

My uncle used to own a Finnish built Marina 75 motorsailor which got 30 NMPG at 5 knots using a 12 HP Yanmar diesel.

So actually, the mileage figures for the MC27 are not so outrageous. It is just that most power boats are badly designed from a fuel efficiency point of view. Most naval architects can do better, but clients don't generally seem to care. Most boats the size of the MC 27 weigh nearly twice as much and have large V8 gas engines giving speeds of 40 knots or more. However my observations of actual cruising speeds of fast boats here in British Columbia indicates few exceed 20 knots and most run at 12-14 where they make an enormous wake.

Wakes are wasted energy. The MC27 was designed to make minimal wake and is optimized for efficiency at real world speeds at the sacrifice of maximum speed. Of course as a sailor I think 25 knots is VERY fast but many boats this size can do twice that.

[peroxyd]

Originally Posted by D'ARTOIS

I think you should read the story of Eilco Casimir, he circumnavigated the world in a small motoryacht, named Bylgia, designed by the Dutch architect Dick Koopmans Sr, with great succes. I followed this story, I knew Eilco personally, a remarkable Dutchman BTW and - that boat still excists!

If I can find any pics and/or info, I wiil post it.

Eilco Kasemier wrote a book about his journey. In was published in German and Dutch and I am not sure if it was also translated into English.

Unfortunately it is difficult to come by. I just ordered a German copy via a second hand dealer. You can get it:

In Dutch
In German

Chris

[timgoz]

Hello Chris,

Just looking through the thread & saw you are new. Nice to have you.
This is a great forum both information wise (getting or giving), and socially. Alot of good people here.

Take care.

Tim

[peroxyd]

Originally Posted by timgoz

Hello Chris,

Just looking through the thread & saw you are new. Nice to have you.
This is a great forum both information wise (getting or giving), and socially. Alot of good people here.

Take care.

Tim

Thank you Tim,

I just found the forum today looking at the discussion about Alubat and similar Aluminium hull boats. I am not a specialist at all and these kind of boats are for me far out of budget at the moment. But living in Amsterdam / North Holland, I do have a small 5 meter rowing boat with a 5HP engine and hope to be able to buy a 20 - 30ft weekend sailing boat for the Ijselmeer and the Waddenzee. This should be challenge enough for me to start with and to learn sailing on my own. True ocean voyages are a dream that is just not in reach for me yet experience and money wise. I will read the forum more frequently to learn more about the one subject that I feel passionate about......sailing boats.

Thank again,
Chris

[Pierre R]

Portager, you have already mentioned Michael Kasten in one post. I am currently looking at the Moxie design as it fits everything you and I are after. Exceptional economy and build costs, low bridge clearance, shallow draft and ocean capable.

You will do yourself a world of good if you drop the requirements for crossing oceans. The structure and design requirements for crossing oceans is not condusive to living aboard and coastal cruising the boat once overseas.

Think building a trailer and going the route of contacting an auto hauler with a roll on roll off ocean liner. The cost of shipping the boat overseas on its own trailer is less than the cost of the safety equipment necessary to do the crossing safely. Cross with mama on a 747 and enjoy the savings.

[alan white]

Economy comes from a displacement hull with a long waterline length and low wetted surface area well matched to the engine's power at cruising speed.
It turns out that a narrow trailerable boat can do this, something like 8 x 32 ft with about 20-25 hp..
The Bolger boat is a lot like this. Very few production boats are made this way. People aren't usually satisfied with 7-8 kts maximum speed, 6 kts cruising speed at 2/3 throttle, but you can achieve 10-15 mpg with such a setup. 300 gallons of diesel would provide 2500 miles with 15% reserve.
Actually there are more sailboats that would make better displacement speed power cruisers out there.

alan

[Pericles]

And then again, along comes Jacques. Brand spanking new. http://www.amateurboatbuilding.com/a...teau/fl26.html

If you want more, see the discussions at http://forums.bateau2.com/viewtopic.php?t=13918

Pericles