Phil Cook wrote:
> And lo on Wed, 16 Jan 2008 02:49:42 -0000, Chambers 
> <ben### [at] pacificwebguycom> did spake, saying:
>> Air resistance might not apply, but manueverability does.  Applying a 
>> force to different parts of the ship will stress different sections in 
>> different ways.  That's a whole lot of differences there!
> 
> Yes except what might be deemed 'travel' ships shouldn't be engaged in 
> high stress producing maneuvers; those are reserved for the 
> fighters/escorts/shuttles, which I agree need to be smaller.
> 
>> Besides which, weight is out, but mass is in.  So smaller is still 
>> better.
> 
> No because a) although you need more oomph to get the ship 
> moving/stopping that's a one-off cost

It's a four-off cost.
1) Cost of materials to build a larger room
2) More fuel needed to accelerate the additional mass
3) More fuel needed to decelerate (brake)
4) More fuel needed to carry the additional fuel for 2) and 3) above.

> and b) volume doesn't directly 
> equal mass; if I increase the height of a room the only mass increase is 
> in the walls and 'air'.

While volume != mass, as your rooms grow in volume, the mass needed to 
enclose them also grows.  It's not a linear relationship, but it is there.

> Create a 7 unit cubic room with walls massing 1kg per square unit (all 
> the same thickness). You're pumping it full of a gas that masses 0.1kg 
> per cubic unit. So the mass of the initial room is 328.3kg. Now increase 
> the height of the room by 1 unit and you get 361.2kg a ~10% increase in 
> mass for a ~14% gain in volume. Make it all 8*8*8 and you get a ~49% 
> volume increase for a ~32% mass increase.

But what is that 32% mass increase is not feasible?  What if an 
additional 10% isn't feasible?  This is a government funded project, 
remember, and their budget is spread over many things - not just the rec 
room for the astronauts.

> Not that I'm saying 'Hey why not make all the rooms 300ft square' at 
> some point you hit overkill, what I am saying is make the rooms the size 
> they need to be for everyone to use them comfortably. So no ducking 

And the point was that it's not reasonable to just make it as big as you 
want; due to the (assumed) constraints, this is the ship that was 
created.  A bit cramped, yes, but it gets the job done.

-- 
...Ben Chambers
www.pacificwebguy.com

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