🚀 go-pugleaf

> Edward V. Wright writes:
>
> Bruce's "quick and simple" concept requires *two* new designs.
> You couldn't just put 5x the cargo into an existing DC-1.  Unless
> it was unusually dense, it wouldn't fit into the cargo bay.  Even
> if you could, the vehicle's balance would be off.  So you're talking
> a major redesign, then component testing of both the first and second
> stages, then testing both the first and second stages together....
>



        The most likely thing that we are going to want in large quantities
in orbit is propellant.  For example, a Mars expedition using conventional
chemical propulsion might require something like 5000 tons initial mass in
orbit, most of which is LOX and LH2.  To transfer 50 tons of LOX and LH2 to
orbit in a DC-1 using a lower stage, the DC-1 upper stage simply flys with an
empty cargo bay.  The DC-1 will then have 50 tons of available propellant
remaining in its tanks when it reaches orbit. The tanks will need the
addition of some internal baffles and propellant acquisition devices to allow
transfer of propellant in 0-G, but this technology must be developed anyway
for any scheme in which propellant is brought to orbit in small amounts and
used to tank up a larger vehicle.



--
Bruce Dunn    Vancouver, Canada   Bruce_Dunn@mindlink.bc.ca