Patent ID: 8091835

Claim:
An exchangeable propellant cartridge system, comprising: a cylindrical main fuel tank having a docking end and an internal end; a conical docking adaptor coupled to said docking end of said main fuel tank; a first interstage having a plurality of cross-support members arranged in a cone shape and pressurant bottles, said first interstage coupled to said internal end of said main fuel tank; a cylindrical oxidizer tank having a main fuel tank end and an avionics shelf end, wherein said main fuel tank end is coupled to said first interstage; a second interstage having a plurality of cross-members arranged in a cylinder shape, said second interstage being coupled to said avionics shelf end of said oxidizer tank; and an avionics platform coupled to said second interstage, said avionics platform comprising an avionics support system; said main fuel tank having a diameter larger than the diameter of said oxidizer tank; and said main fuel tank being positioned coaxially with said oxidizer tank.