Re: Re: starship-design: What is safest?

[Kelly St <KellySt@aol.com>]

In a message dated 12/9/97 1:17:11 PM, zkulpa@zmit1.ippt.gov.pl wrote:

>> From: TLG.van.der.Linden@tip.nl (Timothy van der Linden)
>> 
>> It is almost a fact that every two-way mission needs to get its fuel for 
>> the return-trip from the target system. That is, if you want to decrease 
>> cost (and thus effort).
>> If a design allows to do without resources from the target system, it means
>> that fuel supplies square, which usually makes bad numbers worst.
>> However most of our designs can't do without resources from the target
>> system anyway, so we have to face that we'll need some form of industry at
>> the target system. This does not necessarily mean that we need complete
>> rocket building factories, but instead specialized fuel or other bulk ore
>> collectors.
>> 
>> The question is how much effort would a one-way mission save? It likely 
>> does need less bulk resources, but more specialized resources. There's 
>> a big chance that both kinds of mission will cost as much.
>> 
>> There is however a big advantage of staying in the target system, rather
>> than "floating" through space another 10 year. In the target system you 
>> have all the resources you want (including energy), but in space you've 
>> nothing. Also in the target system you won't need your most critical 
>> (and likely most deteriorating) part of the ship: The engines.
>> Kelly continously tells us, that to stay at the target system we need to be
>> selfsufficient. But don't we need to be selfsufficient if we stay from home
>> 20 years (which is the minimum time for a two-way mission)?

No, thats the whole point.  If we can keep the total mission length less than
the time the that ships systems will start needing major repair, and within
the amounts of stored food we can carry.  We dramatically cut down on the
servicing requirements, and hence needed crew size, repair suplies, and ship
size.


>> In short, I'm not so much wondering what is cheaper, but more about what is
>> saver. Or to put is less subjective: What has a bigger chance 
>> of succeeding?
>> 
>Yes, I do agree with the above.
>My talking about costs has been prompted mostly by Kelly's
>latest arguments concerning costs.
>In one of the previous periods of this one-way discussion,
>I used mostly just the safety argument -
>in my opinion strongly in favor for the one-way mission
>(provided the target system has enough accessible resources). 
>
>Generally, though, I am not some single-minded enthusiast
>of just the one-way missions. I want only to consider
>this mission type as one of the viable options to discuss
>calmly its pros and cons. What prompted my sometimes
>heated argument with Kelly on this issue was Kelly's
>constant labelling of one-way missions as "suicide" missions
>(which I think is simply wrong) and dismissing them
>as outright unacceptable on this ground.

I deliberately refure to them as "suicide" missions for two reason.  First to
emphasis that that is how they will be perceved as by the public.  Secound
because I beleve the odds of outliving the dieing ships systems decrease
exponetially as you significantly extend the mission length.  The later can be
compensated for by an exponential increase in ship suplies and crew resources,
but the later is unchangable.


>-- Zenon

Kelly