The N prize caused me to look this up
A dense paper about launch regulations:
the real thing:
seems like the rocket has to be guided to allow a predictable orbit, thats tough.
some mass ratio calculations assuming 1-4km/s exhaust velocity and 7km/s orbital velocity.
%8 = 5.754602676005730436866499705
%12 = 1096.633158428458599263720238
Sweet they only put actual vehicle costs on the budget not the more costly licensing and other bureaucratic issues. Somewhere I found mention that launchers actually don't make such a large portion of the launch costs but all the other stuff like range operations.
Exhaust speed obviously matters. Here is a nice table for engines
High exhaust speed requires difficult to handle fuel, consider staging. Staging might need even more control systems and structure and drive up the price+weight.
High altitude thrusters seem to be simpler.
Here is a starter book for liquid engines.
Liquid oxygen might require insulation, more weight added.
a practical one:
giving 0.8 km/s ve.
You will start at zero g what will do that to the fuel?
Enough for today. Zzzzzzzzz...
Another day has begun.
The Nprize group had this to say about SpaceX - snide bastards:
The Introduction states: There must be no recontact between the separating bodies, no
38 years is a lot of time to forget something.
The idea with the cannon as last stage should be silly since most explosives don't store much energy
also the acceleration is nasty.