# Re: Re: Summary A

```Timothy van der Linden
To Kelly,

> >> This assumes you can quite accurately steer a packet,
> >> but a packet is build up of a lot of small particles all
> >> going their own way (of course mainly forwards). ----
> >
> >Who says?  A fuel packet could be the size of a fright car of that would
> >help, but I'ld assumed it would be smaller.  More like pill to bear can
> >sized.  It would almost impossible to spray a charged fog of particals out
of
> >a gun and keep them together.  Their mutual repulsion would cause them to
> >defuse to much.  You'ld have to pack them in mini-containers.  I supose
you
> >could treat those containers or packets as particals, but I don't think
thats

> Yes, you are right, lets assume packets of 1 kg. Can we
> accelerate them up to 1E8 m/sec in an accelerator of
> a few hundreds of metres?

Well It will be an order less given the lack of a deceleration capacity of
the ship from a higher speed.

Actually I was thinking bigger fuel canisters might be better.  The ship
could stear a few big canisters to itself with laser propulsion system set up
on the ship.  that would probably allow it to scoop up launched fuel that had
drifted farther off course.  (I sent out a summary page discusing that.

> I guess, I'm a little overwhelmed by the amount of energy
> again, but forgetting that, are you planning to use
> magnetic or charged acceleration?

Doesn't make any diff to me.  I'll try to run some numbers off using the
equation once I work out the needed ship masses.

> Let do a quick calculation about the acceleration needed:
> v=x*t  a=v*t --> a=v^2/x = 1E16/100 = 1E14 m/s^2

Ouch, 10 trillion G's!!!!

> >>>I really wish I had some numbers on the power a mag
> >>>launcher takes
> >>You could calculate the least amount of energy very easely
> >>if you know the exhaust speed and the amount of mass
> >>per second.
> >If you send the equations along I'll run some numbers through for my
summary
> >documents.

> Non-relativistic: Power needed = 0.5 M Vexh^2 Watts
>   M=Mass per second  Vexh=exhaus velocity  (I'm sorry that it is so simple)

> >You could rig up the systems to degrade in capacity not just fail.  But
the
> >more detailed the structures (like the inside of Nanos) the more slight
> >defects will disrupt the function of the system.  (I'n not optimistic
> >Nanos longevity in radiation fields.)

> What I was hoping is that the quantity could overcome the quality: A lot of
> nanos could undo the work of a few broken-nanos. Untill the amount get
75-25
> still a lot of work can be done. Of course this doesn't rule out the
> statistical breakdown after a longer period. But only the few extremeties,
> like the 1:1000 chance of not working directly after manufacturing.
> I'm quite sure that if we made chips today with size as 10 years ago, we
> could make them much more robust.
> OK, all in all, redundancy only works to reduce the number of incidences,
> but not the total "decay". But the number of incidences may be quite high
> without redundancies.

A complex issue.  Can you tollerate electronics no better than 10 year old
ones?  Thats a 100 fold decrease in capacity?

> >> The only problem is that higher-tech (not highest-tech)
> >> has only few redundancies because that isn't efficient
> >> in our society.  About highest tech, we won't be using
> >> that much, since it is inherently dangerous to use systems
> >>  that haven't proven their workings enough.
> >
> >Redundancies start to drastically degrade the performance of some systems
> >(like I.C. chips), and we may (or may not) need all the performance we can
> >get for a starship.

> Maybe this is something that we did not dig out enough, we all assumed that
> the engine designs we came up with would work without much problems for
most
> of the time they were needed. But is it really that easy? I wouldn't like
to
> have two enormous engines and one of them suddenly(?) stops working. In the
> best case we could turn of the other within time. Worst case, the starship
> would start to rotate an be ripped apart by all the abnormal g-forces.
> Besides this, can we savely have an engine shutdown for say a week. I can
> imagine that for beamed energy this may be a problem. (eg. Non matching
> speeds of beamed matter). So how much backup do we need, does it mean that
> the whole ship gets twice as big?

Beamed power wouldn't care, but my fuel launcher (10 trillon G's!!!!) would
get disrupted a bit.

As far as engines I guess we make the parts we can very redundant and the
rest so simple and relyable as to be fool proof. <Then we worry a lot>

> >Anyway, in a political arena peoples techno prejidices will effect the
> >projects and the protest to them.  Every analysis of nuclear powe shows
its
> >not capable of poluting as mouch as the coal plants it would replace.  Yet
> >nukes get intense public and governmental polution and safty attention,
coal
> >little.

> Yes, it's sad, however a single mayor error in a nuclear plant can make a
> whole country (like the Netherlands) inhabitable for a long time.

Actually not is the plant is designed well.  Here in the U.S. we had a powe
plant called three mile Island (bet you heard of it) where the operators were
runing it at full power with ot coolant, they even overroad all the emergency
anti-melt down system as they tried to engage.  The plant was designed so
well it showed no effects of its melt down.  The operators didn't even notice
it happening!  Without laboratory equipment you couldn't even detect an
effect outside the are. No significat radiation increasde (I.e. it always
radiated less than a runing coal plant).  Of course the reactor core was
ruined  (anyone for 4 billion \$'s worth of radioative slag welded to the
insdide of a reactor case imbeddxed in 10 feet of concrete?).

> Anyway lets hope fission or renewable energy will soon replace most of
them.

You probably meen fusion.  Maybe eventually, but in the present political
climate not a chance.  Renewable  produces to little power and has too many
health and safty problems.  Utilities here are figuring on natural gas fueled
fuel cells as the next big wave in power plants.  Probably the basic power
for the next 40 years or more.

> >> Are you also thinking that hibernation is more or less
> >> trivial?
> >
> >No, just that I beleave the public thinks it is.  But in politics reality
is
> >unimportant, impressions are everything.

> Indeed, maybe it is time to start a (yet another) new science fiction
series
> to promote our ideas and collect money by selling T-shirts, computergames
> and stocks for our company to be (Live internet discussions and camera
shots).
> (I'm not really kidding...)

Well I was just telling Dave LIT needed to get more high profile...  But I'm