Problems

[Brian Mansur <bmansur@oc.edu>]

Brian
To Discusion group.

 Now that I have a concept of how to get a sail driven starship to TC in 
less than 50 years, I'm trying to get some questions answered on the ship's 
dry weight requirements and whether or not they can be met.
My Argosy design, as of last night, requires:

1000km wide sail.
A crew of 400
An exploration module (ion drive plus habitat) weight of 350,000 tons minus 
reaction mass
A maximum cruise velocity of .75c.
A minimum power requirement of 1E18W.

1.  Can a 1000 km wide sail made mostly of chicken wire or flimsy silver 
foil be rigged to support a 350,000 ton ship without being ripped to shreds? 


2. Will the guy wires/cables snap under their own weight given a 10m/s^2 
acceleration?

3. How heavy would the cables need to be to prevent snapping.  Tim gave me 
some equations a while back when I wanted to tether a solar collector array 
to Mercury.  I haven't had time to try to make sense of them but he said the 
cables would probably snap under their own weight.


We've got to get these problems solved if this Argosy idea is going to go 
anywhere.