On Fri, Aug 05, 2016 at 06:27:20PM +0200, Abu Dhabi wrote:
> Speaking of sensors, I'd just go overboard with backups - basic military
> sensors are very cheap in space and credits, and being blinded because of
> destroyed sensors sucks. For weapons, I'd figure an even split between
> various types of lasers, missile launchers and sandcasters, plus a couple
> of bay weapons. Typical 4-point crystaliron armour - though not sure about
> that, since it would seriously inflate the cost of the already ginormous
> (~10 GCr) hull cost.

10 GCr seems quite reasonable for an armoured hull suitable for space
habitation, about the size of the Empire State Building but with
vastly greater structural strength and compartmentalization.  Nothing
about such a space station is going to be particularly inexpensive.
The systems inside are going to be pretty pricey too when you add them
all up.

Given that it has weapons, it's reasonable to expect that it will need
comparable armour too.  A mostly unmaneuverable space station is the
last thing you want to be a "glass cannon" if it comes to a fight.

Doubly so since it will have lots of other vehicles docking with it,
accidents will happen, and they probably don't want thousands of
civilians to die because someone shaved the cost down a little by
skimping on hull toughness.

Still, these sort of problems do happen in real life.

> Overall, I'm thinking 50 kilotons:
> - 20 kilotons of quarters,

This looks fairly high as a fraction of total volume.  I'd guess very
much less than 40% for quarters for a space station, though it may
depend upon what purposes this station is designed to serve and what
sort of culture it is going to have.

For most purposes I can think of though, there would be at least a
similar amount of space dedicated to where the inhabitants work, as to
their private spaces.  Probably quite a bit more.  This will include
station operations, but for a "starport" type station I'd expect the
great majority of work would be providing services for people passing
through.

Then there's likely to be storages spaces to include things like
warehouses for transshipment, fuel and so on, which ought to be quite
large in volume, especially since a typical turnaround time for
interstellar transport is a couple of weeks.

Then there are shared public spaces that may take up as much space as
any of the previous or even all of them together.

I'd also expect that it's going to have a great deal of volume
dedicated to accessways - corridors, transport tubes, whatever.
Probably at least as much as much as all the previous spaces combined.

So maybe a baseline of:
 3 kdT quarters;
 7 kdT drives, plants, weapons, sensors, fuel, food, water, air reserves etc;
 13 kdT cargo space, shops, corridors, facilities and other amenities;
 20 kdT corridors, internal transport, and other ways to get from A to B;
leaving
 7 kdT free to assign further.

- Tim