Re: Comparison of Sail vs. RAM (Was Laser Aperture Size)

[Kevin C Houston <hous0042@maroon.tc.umn.edu>]

Kelly
> Lee:
> >Assuming it doesn't require more power to rotate the particle than the
> >energy it produces...
> 
> More power than a mater anti mat reaction?  Humm.
> 
> >Funny you should new tricks and quantums in the same breath though. Did you
> >know that quantum energy appears spontaneously in space? Hmmmm....
> 
> Zero point energy?  Yeah, interesting and potentially huge.

You guys never cease to amaze me.  My maser Idea, which although requires 
some large RM loads, _might_ work -- this you dismiss as "unworkable".  
Then you go on to talk about changing matter into anti-matter, and 
quantum zero-point energy (the ultimate free lunch)  hmmm...

Not to critize, just thought it was interesting.  I got my system back 
up, I will try to re-work the original MARS idea, to see just how much 
extra RM is needed.  

To recap the problem:

if a chemical or fusion rocket is used, (with extremely low Ve) then the 
ship needs planatary sized fuel tanks

if the Ve (exhaust Velocity) is increased to .9996 (or higher) of C, then 
mere Kilograms/Sec of RM is needed.  However, in order to do that, one 
needs lot's of energy, and the momentum of the maser overcomes the 
momentum of the engine.

Somewhere in between is a solution.  that is to say, that at some Ve (I'd 
guess in the .6 to .8 of C range)  The Energy requirements are low enough 
to reduce the Maser thrust to a value far enough below the engine thrust 
to allow a not-too-big RM tank to handle it.  Here is a conceptual graph 
to illustrate what I mean.

+  - amount of Reaction Mass (RM) in Kg/sec needed to decell at 1 G
     taking in to account the size of the RM tanks, and the maser
     "push"

*  - amount of Maser-induced thrust at that energy

   | ++++                           *   
   |     ++++                      *    
T  |         ++++                 *     
H  |             ++++            *      
R  |                 +++       **        
U  |                    +++  **          
S  |                       oo          
T  |                    ***  ++        
   |                 ***       ++      
   |             ****            +     
   |         ****                 +    
   |     ****                      +   
   | ****                           +  
   ------------------------------------
    6              Ve (as % of C)   99.96

Note:  This Graph is totally arbitrary and qualitative.  I'm fairly 
confident that the oo point (where the lines intersect) exists, I just 
have no clue as to how to find it (aside from trial and error which is 
what I intend to do this weekend)

Any help will be greatly appreciated..

Kevin Houston