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Wayne.B

On Thu, 02 Aug 2007 18:16:04 +0700, wrote:

So there you go. A sixty ft. mast and enough dacron to build a circus
tent, a 75-100 H.P. auxiliary engine and a generator set.

My point was that if you put a couple of *big* alternators on each
engine you don't really need a generator, and what would have been the
generator engine can now drive an off center shaft with a folding
prop. That way you can have it all more or less. If you want super
reliability, it is also necessary to have seperate fuel tanks for each
engine with appropriate transfer and filtration plumbing, along with
seperate batteries, etc.

Your engine sizing estimates do not take windage into account which
can be considerable on a 60 footer trying to motor into a 30 or 40 kt
headwind. And yes, sometimes it is necessary. I also take some issue
with your comparison to single engined commercial boats. Those boats
almost always have spacious engine rooms with room to work, lots of
essential tools and spares, and someone aboard who knows how to get
the job done. That is not the case with most 60 foot sailboats that
I've seen.