Looks to me that a Lofstrom launch loop might be a completely natural fit
for launching SPS systems. It's a high throughput launch system, equatorial
and so far as anybody knows, within todays technology.

Launch loops are believed to have a lower limit of launch cost of about
$3/kg and even for smaller/cheaper versions it's down at about $300/kg which
is still adequate for SPS. The loops are capable of at least a GTO
insertion, which would be good for geostationary satellites. And they're
able to carry people as well; the g-force is only around 3; so space tourism
could be a sideline.

They're a bit complicated though, and some of the failure modes are not
ideal, but with sufficient redundancy they should be possible and safe.
They're also potentially non polluting, unlike rocket solutions which tend
to form nitrogen oxides in the exhaust wake.

--
-Ian Woollard

We live in an imperfectly imperfect world. If we lived in a perfectly
imperfect world things would be a lot better.


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