message 0173

• Docking at a space station

>From: nancy ott <ott@ansoft.com>
>Subject: cherryhlist
>Date: Thu, 10 Jun 93 9:29:07 EDT

> >Date: Fri, 4 Jun 93 06:51:37 -0500
> >From: bjgaed@ccmail.monsanto.com
> 
> All this discussion of jump- and rocket-drives has brought up a 
> problem that has puzzled me for a long time:
> 
> All indications are that ships in the Union/Alliance universe dock 
> at the rim of a station.  How does a ship maneuver to match spins 
> with the station rim?

And I always wondered how a station could keep a nice, even, 1-G
rotation when a rather large ship like a carrier suddenly attaches
itself to the rim.  The really massive ships (like ore carriers) dock
at the zero-G central axis of a station.  But it seems to me that even
a normal-sized ship would have enough mass to throw off the station's
spin.  (Think of how the small weights on an automobile tire affect
the tire's balance.)  And since the dockside is typically the level
that's farthest from the axis of rotation, the effect of adding or
subtracting this mass would be more pronounced.

"Downbelow Station" mentions a hydraulic system that compensates for
this, but it seems to me there would still be some sort of disruption
when a ship docks or takes off.  After all, it would take time to
slosh water around in tanks to compensate for the change in the
station's moment of inertia.  Perhaps the mass of most ships is small
enough compared to the station's that ordinary dockings or undockings
don't affect the rotation enough to be a problem....but a group of
ships undocking at once would be a different story. 

--
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nancy ott      |  What is more arrogant than honesty?
Ansoft Corp.   |  
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