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Re: RE: starship-design: Modular Ship Design
X-From: lparker@cacaphony.net (L. Clayton Parker)
To: KellySt@aol.com, starship-design@lists.uoregon.edu
Kelly,
> -----Original Message-----
=====
> You missed the part of my statement about fuel constraint. A
> given weight of
> fuel, only has the energy to accelerate the ship to a given delta-V. It
> doesn't make much difference (speed wise) if it burns all the
> fuel quickly, or
> slowly. So I figure at 1 g my fusion systems could get you about
> 4-5 months of total thrust.
No I didn't miss it. I wasn't holding the mass of the fuel constant, I was
adding MORE fuel to compensate which is whay I said it required more engine
since adding fuel increases vehicle mass, in order to maintain a constant
acceleration you have to increase thrust, which means you consume more fuel,
etc. but it does work out in the math.
I think I figured out that to get a .4C delta-V you needed something like a
40-100 to 1 fuel ratio. (hence my interest in a no tank fuel). That only gets
you about 4 months at 1G. Magnifiing that to get more delta-v would require
stagering fuel quantities! The engines might need to wiegh an order of mag
more then the unfueled ship!
Kelly