Questions in relation to the design of Rockets

[trfinck]

Hey everyone, I'm in the process of designing a rocket that could achieve high(er) altitudes. Of course, I want to make the rocket as small as possible, but maximize the height. I understand that the Mass fraction of the craft should be 0.91, where 91%~ is fuel/propellant, 6%~ is payload, and 3% is structural.

My basic question is, assuming my initial weight(total) was around 500kg, what would be the best propellant/fuel to get the most distance? (cutting out factors such as air resistance and so forth)

Thanks in advanced!

 

[enigma]

Your mass fraction should be as high as you can make it. It just works out that 9:1 fuel to everything else is a typical value. The final velocity (and as a result the high/distance it can travel) is entirely dependent on the specific impulse of the fuel and the mass fraction.

That said - you need to define a little bit more. Are you talking solid rocket, hybrid rocket, liquid rocket? Are you really building something, or is this a thought experiment? Does it need to be practical, or would killing a bunch of people in range of the exhaust plume be ok?