Re: starship-design: We need to get on the same (pellet) track first

[kuo@bit.csc.lsu.edu (Isaac Kuo)]

KellySt@aol.com wrote:
>In a message dated 8/18/97 8:44:27 AM, kuo@bit.csc.lsu.edu (Isaac Kuo) wrote:

>>Particularly pertinent to this discussion is research into hydrogen
>>pellet accelerators for magnetic fusion reactor fueling, since these
>>same pellets would be ideal for the fusion ramjet I'm proposing.
>>Muzzle velocities of over 3km/s have been demonstrated, but I
>>suggest thinking in terms of only 1km/s or so because the fuel packets
>>will ideally have a lightweight railgun with a limited power supply
>>(on board fission and/or collection panels for ship based beamed
>>power).

>??   Ah, given the speeds of the ships were talking about we'ld need muzzel
>velocities of 100,000 km/s to launch the pellets.

No, for a few reasons:

1. Over 150,000km/s is needed to catch up with a .5 cruising starship.
2. A railgun launcher probably couldn't be built big enough to
   acheive 100,000km/s muzzle velocities anyway.  Remember?
3. Thus, you'd need some other way to acheive the 150,000km/s+
   velocities (I propose RPB magsail propulsion, but laser sails
   are another possibility).
4. The railguns are used for the pellet shooters.  There isn't any
   hard lower limit on the muzzle velocity needed, other than being
   able to lay down a long enough segment of track in a reasonable
   amount of time.  I think rate-of-fire will have more of an impact
   than muzzle velocity.
-- 
    _____     Isaac Kuo kuo@bit.csc.lsu.edu http://www.csc.lsu.edu/~kuo
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