[PSUBS-MAILIST] Re: Sailing (Re: Psub for Lew)

["Michael B. Holt" <mholt@richmond.edu>]

Lew Clayman wrote:
> > In 1964, the British Sub-Aqua Club produced the plans to a glider
> > that a diver would ride in a prone position.  With long wings, it
> > would soar and glide just like an airplane.
> 
> Gotcha, riding thermals...

Or gradients in salinity!
 
> > The sailing idea is a development of that.  Let fly a couple
> > of long spars supporting real sails, and let the current
> > pull along a tiny sub.  It would not work in rivers and in
> > restricted waters, but in the open ocean it'd be slow,
> > awkward and less expensive than nuclear for long distances.
> > The physics of it would be the same as the physics of any
> > sailboat.
> 
> Losing you now.  Downwind (downstream, downtide) is no problem, but
> for reaching (current perpendicular to course) or moving against the
> current (air sailboats can not sail directly against the wind, but
> can get to as close as 30 degrees against the wind) puzzles me: what
> prevents leeway, and what prevents excessive roll, in a "sail-sub"?

Those are the problems.  It's fine for downwind, but anything
other than that will be ... challenging.  My first guess is that
any course closer than 90 degrees off the wind will be difficult
at best.  Going into the wind would require more sail than 
we have ocean, I suspect.  I've never seen any studies of the
idea.

This is the same idea as sailing in space, using the wind of
solar particles.  It has the same problems.   



Mike