Abstract: A method includes depositing beads of solid propellant material using additive manufacturing to form a fuel element for a rocket engine, the fuel element including beads of solid propellant material, wherein a combustion port extends through the fuel element, wherein the solid propellant material includes an oxidizer and a binder material.

Abstract: A fuel grain assembly for a hybrid rocket engine includes a hybrid fuel grain including fuel grain material, wherein an outermost portion of the fuel grain material defines an outer surface of the fuel grain, and wherein the fuel grain material includes a polymer based rocket fuel material; and a solid propellant material disposed in contact with the fuel grain material of the hybrid fuel grain, wherein the solid propellant material includes an oxidizer and a binder material, wherein a hollow combustion port extends through the fuel grain assembly, wherein at least a portion of a wall of the hollow combustion port is defined by the solid propellant material.

Abstract: A body mounting assembly, model vehicle, and method for engaging a model vehicle body to a model vehicle chassis are provided. The body mounting assembly includes a latch assembly. The latch assembly further includes a latch member with a latch engagement surface. The body mounting assembly also includes a retainer assembly. The retainer assembly further includes a retainer engagement surface. The latch assembly is releasably engaged to the retainer assembly when the latch engagement surface and the retainer engagement surface are interlock together. A body mount able to be coupled to a model vehicle body includes one of the latch assembly or the retainer assembly and a chassis mount able to be coupled to the model vehicle chassis includes the other corresponding retainer assembly or the latch assembly corresponding to the body mount.