>>13407696I started with liquids in my freshman year of college, back when I knew absolutely nothing about motors. The fuel was ethanol (Everclear) and the oxidizer was low pressure oxygen gas from one of those red bottles you buy to mix with MAPP gas torches. The combustion chamber was a soup can, and I managed fuel injection by loading propellant into a large catheter syringe and manually injecting it. Needless to say, results were subpar.
Now that I'm further along in my understanding of rocket engine principles, I'd like to stay focused on a few engineering problems at a time. The Mark IV is designed with two principle goals in mind: successfully achieve supersonic exhaust from a proper De Laval nozzle, and to safely contain the pressure needed for said exhaust. Ancillary goals include deriving impulse parameters, measuring thrust/chamber pressure, and developing ground testing architecture to support future firings safely.
Solids allow me to focus more on the problems of nozzle and chamber design, without having to worry about the separate issues of fluid propellant injection, storage, plumbing etc. Once I feel I have achieved what I set out to do with the Mark IV, I'd like to move on to a hybrid design for the Mark V to only have to worry about mastering one set of plumbing.
This does sound very "Gradatim Ferociter" to the outsider, but I have the luxury of time and the constraints of being a one-man show. One day, I will return to bi-propellant liquids.
