Re: OK, here the right calculus (I hope)

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

On Sat, 30 Mar 1996, Timothy van der Linden wrote:

> Optimal solution for a maser deceleration starship. The starship carries all
> the necessary repulsion mass and gets the energy needed to accelerate the
> repulsion mass from the maser.
> 
> To do this we want to find the solution that consumes the least energy.

<Equations snipped>

> The minima are:
> 
> Vstart  Vexh optimal  Fuel:ship-ratio  Energy per kg of ship (in Joules)
>  0.1        0.062          5.36            7.45E14
>  0.2        0.121          5.84            3.25E15
>  0.3        0.180          6.40            8.11E15
>  0.4        0.240          7.06	     1.64E16
>  0.5        0.300          7.87            2.97E16
>  0.6        0.364          8.91            5.23E16
>  0.7        0.433         10.38            9.21E16 
>  0.8        0.512         12.72            1.73E17
>  0.9        0.615         17.75            4.04E17
>  0.99       0.803         52.00            3.12E18
>  0.9996     0.906        238.81            2.91E19
> 

So you're saying that a Maser Augmented Rocket System (MARS) _will_ 
work?  do I have that correct.  That we can use maser sail to accelerate 
at 1G constant, then convert the Microwave energy to elec. to accelerate 
Reaction Mass (RM) to about .803 C and we will need 52 times the ships 
dry mass for RM.

Celebratory cheers pending confirmation.

> Note that the power of the maser-beam is NOT constant, it is supposed that
> it decreases while the ship gets lighter (because it repulses mass).

If it's not too much trouble, can you figure this for a constant maser beam
How much extra RM will we need?

A decreasing maser beam is possible, it's only a time delay calculation, 
but a constant beam would solve some engineering problems

and which time frame do I use to figure the energy of the Maser beam?
ship's time or earth's time?

Kevin