Rocket Cost and Space Tourism

Willow wrote:

On Feb 4, 3:09 pm, "Greg D. Moore \(Strider\)"
wrote:
[snip]

Because you can't just look at the cost per kg. (In fact generally they
don't correlate). Look at complexity. Look at other issues.

You have to stage your rocket, that's independent of mass for example, but
can get costly.

I was just wondering whether it is possible in principle to get the
cost down of a rocket.

It is possible in principle, but it remains to be seen if that
principle can be translated into real world practice.

My understanding is that if the raw materials (including propellant
and energy) are cheap enough, in theory if you were an advanced enough
civilization (e.g. not us) then one could turn those raw materials and
energy into rockets for essentially the cost of raw materials (and energy).
Maybe I am wrong - but it is a valid question to ask.

Why do you believe we are not advanced enough?

What do you mean by complexity? The number of parts? The complex shape
of each part?

Yes to both. Plus the difficulty of manufacturing the more complex
components. Plus the cost of using esoteric and/or cutting edge
techniques to assemble to individual components into larger
assemblies. Plus the cost of engineering and QA, which scales non
linearly with those factors, and not at all with raw weight.

Maybe an advanced civilization would be able to produce anything for
the cost of raw materials and energy. So why can't we?

For the same reason we can't produce an arbitrarily complex computer
program for the cost of the raw materials and energy.

Now you're starting to get somewhere. Those are definite factors but far
from the only ones. Compare the cost of a fighter/kg vs the cost of the
aircraft carrier on a /kg basis.

Again why do those things cost so much? It's a valid question.

For starters - mass production. The bulk of the weight of an aircraft
carrier consists of standardized plating and structural members. Even
though we are only assembling one every couple of years, the savings
via economies of scale add up quickly.

D.
--
Touch-twice life. Eat. Drink. Laugh.

http://derekl1963.livejournal.com/

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL