"Pat Flannery" wrote in message
...

Did you catch the part about no ballast tanks, and the sub being held on
the surface by those four vertical thrusters? So in other words, if the
power fails.... yes, this is a Russian design. :-)

So what we have is a heavier-than-the-medium fluidcraft, right? We've been
doing that for 100 years with air, don't see why water should be any harder