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

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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

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