Optimal design of an Australian medium launch vehicle

Conceptual design of a satellite launch vehicle is a multidisciplinary task which must take into account interactions of disciplines such as propulsion, aerodynamics, structures, guidance and orbital mechanics. We discuss the initial modelling of a clean sheet design for a putative Australian medium launch vehicle capable of placing an Ariane-44L equivalent payload into geostationary transfer orbit. While the Ariane-44L vehicle design is a three and a half stage vehicle, the alternative design is for a straight three stage vehicle. The “ideal velocity” or delta-V capability of the AR44L is first derived from published data. The proposed design is then modeled using a spreadsheet. The gross lift-off weight of the vehicle is then minimised while still providing the same delta-V as Ariane. Various differences between the two vehicles are discussed. The initial design of a launch vehicle as presented here is based on a simple stack model optimised automatically using an evolutionary algorithm. The efficiency of the proposed approach and the reasons for using evolutionary algorithms is discussed along with future developments in the areas of multi-objective formulations of the design optimisation problem as well as the vehicle model from the standpoint of a number of system considerations.