🚀 go-pugleaf

In article <1992Dec18.025923.12966@cs.rochester.edu> dietz@cs.rochester.edu (Paul Dietz) writes:


   In article <STEINLY.92Dec17183740@topaz.ucsc.edu> steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:

    >Now, DC-1 wants something like 300 tons total, so 75 tons LH2
    >and 225 tons LOX? That's still 30 fuel trips, maybe doable with
    >three shifts in 24 hours, but I don't think you can do it in 8 hours?
    >Not with one crew.

   You mixture ratios are off.  The oxygen/hydrogen mixture ratio
   in the SSME is 6; in the Saturn J-2, 5.5.  At a ratio of 6
   this would be about 43 tons of hydrogen and 257 of oxygen.
   About 20 trips.

Ouch, I'm not doing well here, for some reason I was thinking
4:1 and writing 3:1...

   However, the launcher would almost certainly have fuels piped to it
   directly from remote storage tanks, as NASA currently does at the
   shuttle pads.

But now we're getting further and further from the "DC concept"
with fixed launch platforms and some serious ground infrastructure instead,
at this point an honest cost evaluation should include running
the tank farm and pipes, those are fixed costs almost independent
of flight rate and this starts to look more like the shuttle.
No more popping off from the nearest convenvient airport at
short notice...

|  Steinn Sigurdsson	|I saw two shooting stars last night		|
|  Lick Observatory	|I wished on them but they were only satellites	|
| steinly@lick.ucsc.edu |Is it wrong to wish on space hardware?		|
| "standard disclaimer"	|I wish, I wish, I wish you'd care - B.B. 1983	|