Re: starship-design: What is safest?

[TLG.van.der.Linden@tip.nl (Timothy van der Linden)]

Kelly wrote:

>>What military system HAS to work? Virtually all systems have backups of some
>>kind. While the backup is being used, the primary system can be repaired or
>>replaced with all the outside help that may be needed.
>>In case of field equipment where no direct outside help is available there
>>too are many (although less efficient) backups available. It would not be
>>very smart to bet on one single system during a fight, no matter how well
>>designed.
>
>To a degree ALL important systems are dedsigned that way.  You always make
>sure the failure of one system would * shut everything down, or at least not
>shut it down catostrophicly.  But that not always practical.  Rip one of the 4
>tires of a truck or car, and the vehical is stuck until fixed. Since Military
>equipment is usually operated in as bad a situation as we can find (war) and
>put to the most adverse conditions the enimy can find, and operated away from
>suply and sevicing bases, its has to be very tough.  Just like exploration
>equipment.

[I think you forgot a "not" at the * in the above paragraph]
It has to be tough, but not into extremes, since backups are available or
will be shortly. I'd guess that if military cars had to be made more
reliable, they should not use air-pressured tires. Chances of a car getting
stranded by a punctured tire on rough terrain seem to be rather high.
BTW Many succesful explorers from the past used equipment that they could
repair or rebuild themselves without outside help. Several expedition
leaders designed equipment with that criteriom themselves before they went
exploring.

>>When parallel computing is made to work, then making computers more robust
>>is supposed to be easy. Furhermore superconducting magnets are great to
>>avoid mechanical wear. (I'd suggest you'd use these on your hab train.)
>>Also shielding equipment from a normal moist, temparture fluctuating, dusty
>>environment increases lifetime significantly.
>
>Shadow processors are used even now to keep a hot back up, or verification
>systems, on-line.  But sooner or later the computers will fail, and after
>comparativly short service lives.

While some applications may ask for highgrad computing power, many don't
need to. In much electric equipment limits are pushed, something that we
certainly can't trust to do in our starship.
So we should make circuits/chips that have the computing power of x years
back but use the much more precise and reliable technology of today.
Similar to what Zenon wrote, we shouldn't expect the same luxuries as in our
homes.

>>"Simple" structural loads? While the exhaust of a rocket engine looks crude
>>and simple, the complete engine consists much more than that. I wonder if
>>the fusion engines make the design simpler. That little bit of corrosion you
>>talked about may very well affect reflectivity/conductivity that will
>>escalate the corrosion within seconds (or less).
>
>The fusion engines are far simpler then standard rocket engines.  I.E. few
>pumps, nozzels, no presure vessels, etc.  I'm not clear what you mean about
>reflectivity/conductivity.  Certainly a system with the scale your talking
>about wouldn't have its conductivity effected by surface blemishes.  If its a
>problem, design the system so it will work with the entire surface corroded or
>clean.

If a fusion engine is so simple, then a fusion power plants should not be to
hard to build and maintain either. What I've seen from fusion power designs
is that they look pretty complex, more complex than chemical rocket engines.

>>If an engine part fails, disasterous things will happen. If a circuitboard
>>fails, it likely can be repaired before lifetreathening situations arise.
>
>That depends un what the circut board controls.  Circut failures can and do
>kill people rapidly.

I don't know what kind of circuit failure you mean.

Tim