I've been thinking on Scott's question of how my background in
geology affects my traveller playing. I guess my response is
damn little. Rocks and their geochemistry just doesn't have
much impact on the various mis-adventures of my characters. Igneous
petrology, and the exchange of isotopes in hydrothermal systems
just doesn't help much when the TJ freighter is being chased by
a bunch of vargr corsairs, 'ya know.
I do however, know a great deal about submarines, having a father
who spent over half his life building them, and having worked for
two defense contracters myself who made submarine "toys" when I
couldn't find an honest geology job in the 80's.
Which brings me to something I've been thinking about lately:
the construction of ship hulls. The way I see it, the problems
with builing a hull for a submaine and a hull for a traveller
space craft can't be too different. The man who designed the
Nautilus and the Skipjack once described the problem to me thus: if
all you had to do was put a sphere or a cylinder capped by hemispheres
in the water, then there would be no problems in making a hull that
could withstand the deepest oceanic pressures. The problem, he said,
was that you had to make holes in the hull, for the drive shaft, for
the hatches, for the cooling water intakes. It's the holes that are
the "weakness" in withstanding the great pressure gradients.
In addition, there is the technological problem in making a one-piece
hull. Early submarines were rivetted together! (remember the great
scene in Das Boot where they had to dive to bottem near Gilbratar, and
the rivets starting popping in the hull?) One of the tremendous advances
in sub design that came out of Electric Boat in the 50's was the ability
to weld the thick hull plates together. It's the welds and the perforation
of the hull that are the zones of weakness, not the material of the hull.
If you make a one-piece hull out of a thick enough material (read metal),
then you can withstand greater pressure gradients (no, I haven't forgotten
that the cylinder has a limitation on diameter - I'm blissfully ignoring
it for now.)
So what does this have to do with traveller, you ask? Well, first, we've
been assuming that any decent space ship is able to withstand great
pressure gradients, e.g. the Flamboyant hidng in the ocean of Welles
in Scott's 4.5th Frontier War, and also any ol' ship doing refueling in
a gas giant. That means that those ship hulls must be as good or better
as a modern submarine in the U.S. Navy. (I can hear one or two of you
kvetch that the 688 class has an official depth rating of around 250
meters. Well, that's true <I hope I remembered that number correctly>.
But remember, the 688 class has a less than optimal thickness to
diameter ratio. The skipjack class, made out of inferior steel (HY80
vs. HY120) can dive deeper because the designers at EB purposefully
optimized the diameter to hull thickness ratio. The titanium hulls
on the newer soviet subs can dive deepest, but the welding technolgy
is what allows the use of titanium for a hull, and it's a bear!)
This leads me to thinking that "super-dense" materials are not the
correct path to travel down in pursuit of the 57th century space hull.
I opine that it's advances in making one-piece hulls of suitable
thickness that's the trick. If you could weld a hull of titanium or
steel, or better yet, if you grow a single crystal of metal into a formed
hull, then that's what required. The hull perforation problem can be
taken care of by arm-waving good enough iris hatches. But making the
hull itself is the real problem. It's not super-dense materials we
need - it's good enough technology to weld a one piece hull. The
materials we already have are sufficient, so long as we can weld them
together adequately in the thickness required. The welds are the
weakness (or has everyone forgotten the great weld defect scandal at
Electric Boat in 1979, that lead to the cost-overrun fiasco which made
national news <my apologies to the non-US readers of this list>?)
What does super dense really get us anyway? Perhaps better armour
for naval and scout ships. But why invent a new material when what
we have is sufficient (in my opinion)? Not only that, but consider
that those super-dense material are going to be a bitch to weld - and
that's the big problem in my mind anyway!
How do make super-dense, by the way? Do we convince two nuleii to
occupy one set of electron orbitals by somehow negating the tremdous
force of two positive charges trying to escape on another? Do we
make an elastic material out of very dense atoms? Only certain metallic
elements have the property of being elastic, strong in both compression
and tension, weldable, and (most-importantly) non-cleavable. Unless
we "discover" an unknown principal of quantum chemistry, I think we
stuck with good ol' steel and titanium. <I've been teaching
crystallography and mineralogy to a bunch of undergrads, so I confess
I've had a lot of inorganic chemistry on the brain lately...I've been
dreaming of Pauling's Five Rules in my sleep, for crying out loud. Gads!>
I think I've rambled on long enough (my apolgies for the length of this
post - I really didn't it to turn out this long, really!). So what does
anyone else think?
Catie Helm, rock-nerd
[email removed]