A sailboat operates in two mediums, air and water, and the boat is designed
to take advantange of both.
So by definition, you can't sail completely under water. A hydrofoil could
be seen as a boat with the foil under the water, and the boat out of the
water.

A submarine would be, by definition, completely under the water, and the
operators inside the vessel, and you want to have it powered by a sail out
of the water? How do they see the sail, so as to trim it? For that matter,
how do they see where they are going? Sailboats are by definition, bouyant,
and submarines, aren't.

So let's say you are writing a sci-fi novel about our planet (or a simular
planet) where there was a radioactive atmosphere, and no engines for
powering vessels. And the vessel operators can't got topside, ever. If that
were so, why would they want to go anywere with their sailing submarine?
When they get there, they can't get out of the water, so their destination
would have to be under the water (which, somehow has escaped radioactivity).
Hmmm, they'd still be better off with a vessel that was out of the water, as
it would be quicker. But you could submerse it when it got where it was
going. Yes, that's the ticket...


"Lucas J. Riesau" wrote in message
ups.com...
I want to build a sailing submarine.

Is that possible or impossible???