[gurps] underwater sails

[David Scheidt]

On Tue, Jan 13, 2009 at 1:00 PM, Anthony Jackson <ajackson at iii.com> wrote:
> David Scheidt wrote:
>>
>> You can only sail at the interface of two media.  That's normally the
>> interface between air and water, but it can be other things.  Water
>> and water doesn't work; the density difference between the two isn't
>> high enough.
>
> Density difference is unnecessary; it helps preserve the boundary, but if
> the boundary exists for other reasons, you can sail as long as you're on the
> boundary between two regions with different velocities.
>
> In practice, this isn't likely to be very useful underwater, but it's
> theoretically possible.
>

The density difference is what makes it possible to transfer energy
from one medium to the other.  it's how keels work.


-- 
David Scheidt
dmscheidt at gmail.com