Thursday, December 29, 2011

Micro 10’ Sailboat for Global Circumnavigation Part 2



Following on from yesterday’s blog I have a few more thoughts about the type of vessel Sven may design. For some reason he has decided on a length of 10’ which is small for such a venture. Maybe he has chosen that length because he made mention of the Around in Ten Race which never took place. Originally there were a number of aspirants who intended racing around the world in 10 sailboats, but for various reasons none were able to make it to the start line.


The challenge still remains for someone to succeed in doing a circumnavigation in a smaller boat than the smallest, i.e., Serge Testa’s, ‘Acrohc Australis’. She was 11’ 10” long. Ten feet would be pushing it to the absolute limit, on account of internal space for a solo sailor and his provisions. This would not be a non-stop attempt. On that basis, if Sven were to succeed, he most likely would become the ultimate winner of a world record, but I feel sure he would not be looking for accolades or approval on that account. He says he wants to celebrate 50 years of his life during which time he has sailed across oceans aboard small boats, most of them designed and built by him. A solo circumnavigation in the smallest of boats would be his way of celebrating.


Yesterday I suggested Sven’s new boat may turn out to be a bit like Paul Fisher’s Micro 10. Well, that was in profile, not in terms of 3-dimensional form. Instead of having double chines she may have single chines on each side and she may have chine runners as per his present boat. She could even be a round bilge boat, although I doubt it, because his preferred building method is sandwich composite which does not easily lend itself to multiple curved structures.


I also suggested his new boat may be fitted with a skeg to help with downwind sailing, but I remember that he locked the rudder of his present boat, which in effect became a versatile skeg that could be used in conjunction with the sails to bring about equilibrium for maintaining a steady course. His boat may also dispense with a conventional keel because it would not help when lying to a sea anchor or drogue.


One of the biggest problems with small boats is keeping them dry inside. If the crew is to maintain his health over a period of many months he must keep his body dry and warm. On that account, I doubt Sven will swim in the cold waters of the Southern Ocean as he did in the warmer waters of mid Atlantic. He has already perfected a system of watertight vents for providing fresh air within an otherwise sealed cabin, but for this 10’ boat he will need to insulate the interior for maintaining a bearable temperature. Some form of heating may be required, which could pose a problem for the storage of fuel to power a heater. Top quality thermal clothing may be the solution obviating the need for a heater.


Note

Just a thought – Do you think a scaled-down 10’ version of a John Welsford ‘Fafnir’ might fit the bill for a solo circumnavigation record attempt at being the smallest? I wouldn’t choose to sail south of the Great Capes, however. I suggest this as food for thought - not a recommendation. John would give an honest opinion.



Text for the Day

Matthew 5:37 ‘…….. let your ‘Yes’ be ‘Yes,’ and your ‘No’ be ‘No.’ …………………’



Links


Around in Ten

http://www.aroundinten.com/


Serge Testa aboard ‘Acrohc Australis’

http://www.acrohc.com/


‘Acrohc Australis’

http://bills-log.blogspot.com/2009/11/acrohc-australis.html


Upwind in Small Sailing Cruisers

http://bills-log.blogspot.com/2010/04/upwind-in-small-sailing-cruisers.html


Solo Circumnavigation Record Attempts

http://bills-log.blogspot.com/2009/10/solo-circumnavigation-record-attempts.html


‘Fafnir’ by John Welsford

http://www.jwboatdesigns.co.nz/plans/fafnir/index.htm


Boatbuilding Sailing Blog

http://fafnirsailboat.blogspot.com/

5 comments:

Hajo said...

Fafnir's payload is about 450Kgs. With 400Kg in stores and Sven himself (Not forgetting his books) he would be slightly overloaded. Start scaling the boat down to 10 ft and you get about 210 kg of stores he can carry...

I'm afraid a 10ft boat that has to carry 500kg of payload is going to be one ugly duckling. A little like a deep ballasted cork. (And to be honest: if he is not interested in setting records: He might go onshore; accept a meal etc... I really don't get his 10ft self imposed limitation.)

cornishhh said...

A Fafniresque boat would be a complete departure in design from anything Sven has built so far.
It will definitely be interesting to see what he comes up with.

William Serjeant said...

Thanks guys for your comments. Keep them coming.

We may learn a few things from the Sven experience.

I wish him all the best, and I hope he succeeds.

Cheers,
Bill.

Brian said...

Hi Bill. John Welsford drew a 10' boat for the race called Gimli.

https://picasaweb.google.com/109537860552375028906/DropBox?authkey=Gv1sRgCK_u5IHfnrLe2gE&gsessionid=lKaQkCUUhlmTWaSccAr1DA#5691804762601153410

William Serjeant said...

Brian,

Thanks for the link. I did an article on 5th April, 2010 featuring Gimli: http://bills-log.blogspot.com/2010/04/10-ocean-going-sailboat-designs.html

Gimli was designed as an out-and-out micro ocean racer - hence she is more high-tech than Fafnir. She will require a young fit man/woman to sail her to her maximum potential. She's almost the antithesis of Fafnir, a low-tech small ocean cruising yacht. She would not be able to cope with conditions in the Southern Ocean, south of the great Capes.

Sven has acknowledged that he made the mistake of building his latest boat too heavy by incorporating complicated structures. I think he plans to have a free-standing rig for the new boat.

With a lighter, but strong boat, he will have more capacity for carrying the provisions needed for his proposed 12 month voyage. Bear in mind, that he plans to put into land for respite and provisions if opportunities arise.

Bill.