Fred Sanford vs. rocket-hull abundance (was The scrap-hull vs. the E

> The idea is the same whether it is a Sea Dragon being
> reused in orbit or a shuttle external tank being reused:

It is not the same. In a rocket-hull economy, a rocket-hull can be
custom-made to order. An ET cannot. Rocket hulls can arrive by the
thousands or millions. ET's cannot -- even if the Shuttle were not
retiring. The lower stages of Ares V or DIRECT 2.0 might be sendable
all the way up and salvageable in orbit, but they would be dwarfed by
the volume of custom-speced rocket hulls arriving. If you were to say
to someone at a cocktail party, "So far, I've managed to score for
myself five free External Tanks!", the reply might be, "What did you
do that for?"

> that would otherwise be wasted

And there lies the clincher. Disposal of a resource can only be a
waste, as far as that resource is valuable. In an orbital rocket-hull
economy, scrap-material is not any more valuable than about $10/lb
(precious metals excepted; though there had better be a good reason
for their being valuable, and high strength/weight is not on the list
of things Orbitlings like). That would put the value of an ET at
about half a million dollars, despite its acquisition cost of $5
million and its launch cost of $1.3 billion, except for the fact that
I did not order an ET. I might have no use for scrap Al 2195 (the
bizarre "aerospace grade" alloy used to make the ET). It is valuable
on Earth, because Earthlings have to deal with gravity, but it is not
valuable in orbit, because it is difficult to work with. I can custom-
order my scrap material, so I can get the exact material I want, and
have it delivered when I want it. When I do that, I order material
that is easy to render into the shapes that I want, and easy to
unrender when I decide that I want different shapes.

> instead being reused as an orbiting propellant depot

If I want a propellant tank, I want one that can vent isometrically
so that it does not rocket away/go into a spin. I want one that does
not have goofy, orange decomposing foam on the outside producing
hazardous 5-mile-per-second flotsam that generates complaints from
the Orbit Trade Organization and that makes my enterprise look like
an orbiting Sanford and Son.
http://images.google.com/images?q=sanford%20and%20son

Otherwise, you might have a point there.

> or living quarters

This one is a problem. Living quarters need a lot of things that ET's
do not have. Household wiring (data/electricity) is one. Plumbing is
another. HVAC/life-support is a third. MLI (Multi Layered Insulation
= ~20+ layers of aluminized mylar alternating with layers of dacron
mesh (bridal veil)) is a fourth. A fire-suppression system is a
fifth. At least one door would be nice, maybe even one that fits with
my airlocks. I can get those things custom-speced into a rocket-hull,
but not an ET. So there we are back with the clincher: it's not a
waste if it was not valuable in the first place.

> It makes so much sense to get a second use out of
> something that is already going to orbit anyhow.

It might not make economic sense. Maybe it makes some other kind of
sense.
http://en.wikipedia.org/wiki/Packrat_%28person%29

Further reading on cultures of abundance vs. cultures of scarcity, in
the context of software engineering:
http://www.jasmine.org.uk/dogfood/story/article_42.html