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Re: starship-design: How to build a station.

KellySt@aol.com wrote:
> In a message dated 4/20/00 2:45:48 AM, bfranchuk@jetnet.ab.ca writes:
> >With a 40:1 mass/payload ratio 5 tons is a 200 ton space/craft,
> >a bit large for a first time design. How about 2.5 tons... 100 ton
> >space-craft.
> Why do you assume a 40 to 1 ratio?

  There is about a 20:1 mass ratio from the rocket equation
for a ISP of 350. ( lox/ kerosene or lox/ch4 ). If you assume
the mass of the craft empty is the same of the payload, that
becomes a 40:1 ratio.

> Solar in general is expensive.  The panels however are simpler and more
> relyable.

They have been claiming cheap solar panels, as long as the have
been claiming cheap access into space.

> A LOX/Kero rocket based SSTO would use 14:1 fuel/craft ratio.  The air
> breather could cut that to 7-1 maybe less.  Given Kerosine is far more dence,
> it needs a far smaller and lighter tank.

 I just think in the near future +25 years the price of oil/gas will
skyrocket and CH4 will be cheaper than synthetic Kerosene.
> Kelly

"We do not inherit our time on this planet from our parents...
 We borrow it from our children."
The Lagging edge of technology: