Re: starship-design: Engine Parameters

[KellySt@aol.com]

In a message dated 10/8/98 6:23:43 PM, lparker@cacaphony.net wrote:

>Okay, since we all pretty much agree that predicting what the engine will be
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>is impossible, and that the likelihood of something unpredictable happening
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>between now and fifty years from now is at least a non-zero number <G> lets
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>do as Nels suggests and propose a set of requirements that will define
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>performance parameters necessary to propel several different classes of
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>ships. I would suggest basing the classes on a low median and high model of
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>performance based on the following divisions:
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>
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>LOW: Thrust is not continuous, may never exceed 10 m/sec, total change in
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>delta v of 100,000 km/sec (1/3 c)
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>
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>MEDIAN: Thrust may extend for long periods but is not normally for entire
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>mission duration, may achieve transient thrust levels of up to 30 m/sec,
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>total delta v limited to 200,000 km/sec (2/3 c)
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>
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>HIGH: Thrust is typically continuous over duration of mission, maximum
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>acceleration is 90 m/sec, total delta v is 300,000 km/sec (0.99 c)
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>
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>All of these assume an acceleration deceleration phase with no reserve fuel,
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>change in delta v is a maximum only and assumes there is enough fuel to
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>decelerate also (in other words, the delta v figures should really be
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>doubled).
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>
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>Comments or suggestions?
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>
>
>Lee

Accel of over 10 m/ss seem overkill, and painfull.  Even if your going to
light speed a 1 g boost isn't going to really increase your flight time.

Kelly