Manufacture and Test of a 100 km Capable Rocket Airframe

The development of Launch Vehicle 4 (LV4) Airframe aimed to provide flight-ready CAD models of components, supported and verified by FEA, CFD, and mechanical analysis to ensure appropriate factors of safety. The design incorporated full modularity to accommodate future changes in propulsion or payload systems. Extensive physical testing of polycarbonate blend confirmed the suitability of FDM for producing 12-inch ID nosecones with a factor of safety against pressure loading failure of 1.6. Additionally, a two-part pourable lightweight foam was identified and tested for filling gaps in the external isogrid pattern of the fuselage pieces. The isogrid fin can underwent redesign and thorough analysis, including half scale crush testing and FEA analysis, resulting in an updated fin geometry. Key hardware attaching the fins to the fin can was repositioned to eliminate potential failure modes during assembly. Fin material and thickness were carefully selected to minimize mass and drag. Furthermore, an optimal boat tail geometry was chosen and analyzed, providing a 3% increase in efficiency while considering drag reduction versus weight. A design point of an 8° angle of attack (AOA) at maximum dynamic pressure was selected, and all components with stream-wise surfaces were designed with factors of safety ranging from 1.5 to 1.65, effectively minimizing unnecessary mass. Overall, the development of the LV4 Airframe has been comprehensive, resulting in a design that prioritizes safety, adaptability, and efficiency.