Monthly Archives: April 2012

New Designs

The New Design Book is Done

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Finally.  The major upgrade to the Design Book, 2012 is done.  It has been a big deal.  It will go to the printers on May 11 or soonest work day after the 10th.  I appreciate everybody’s patience.

My goal also is to have a CD version with the print design book.  It will be in color and have the hot hyperlinks.  I am using Pagemaker as I just didn’t have the 2 hours it usually takes to get my Indesign permissions taken care of on the new laptop hard drive.  So I will have to run all the Pagemaker files through Indesign when I get back to hot up the hyperlinks.

Thanks again.

New Designs

New Rowing Trimaran

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You might recall that my Formula 40 catamaran hull lines held the world record for fastest rowing across the Atlantic last year. For a day. I did not know about the rest of the design, and a lot was wrong. I insisted on being fully involved with the next boat. Crew of 9. Here it is.

Rower 60 Trimaran

 Features:

Main hull has L/B of 21:1.  Displacement of  4848 lbs.  Hull speed is 11 knots.  At hull speed it takes under 6 hp to move at that speed.  At that speed there is 265 lbs of form drag and 125 lbs of friction drag. Draft is only 12” so change in depth over the trip should not change much, keeping waterline long.

 X bow allows less hull area, reduced windage and significantly less wave pitching.  See video at http://www.militaryphotos.net/forums/showthread.php?152989-Xbow-Sea-Axe-A-future-in-the-Military-Design.

  Next year everybody will have these bows.  Flare is high enough above waterline that it should not increase pitching.   

Total main hull max height is 6.5’.  I say that the governing load will be a wave on each end and the middle in the air.  The flare also helps restrain buckling.

Curved openings are much stronger.  Upwind I would cover openings with Eisenglass or thin acrylic like man-powered craft record holders do.

Top will have solar panels and flush hatches as needed.

 Amas are just under 17’ long and 1000 lbs displacement reserve.  I see greatest load being pushed sideways 20’ by a wave.  Location aft helps minimize pitching again as it spreads out the centers of buoyancy. 

I assume beam should be completely rigid, like in bicycle racing where flexing frame is seen to absorb power.

I see this as having every possible thing done right.  I don’t know if 5’ tall above waterline is too much.  It does give more beam depth.

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