Analytical and experimental investigation of a H2O2-HDPE hybrid autophage engine

This paper presents the advancement of the maturation of hybrid autophage rocket propulsion through AMBRE, the first small-scale prototype of a hybrid autophage launcher. This architecture involves the use of the launcher’s fuel as a structure, removing the need for tanks and halving the rocket’s dry mass. During flight, the length and the mass of the rocket continuously decrease, resulting in a single-stage-to-orbit launcher with a better overall performance and reduced cost thanks to its simpler design and logistics. Following the firing tests conducted in January 2024 by Alpha Impulsion, the integration of the autophage engine continues with several developed subsystems. Insertion of propellants is achieved thanks to an electric embedded system developed and patented by Alpha Impulsion, introducing the possibility of throttling the engine. This solution was estimated most effective for orbital flight in a previous theoretical work and a prototype was tested for integration in the autophage engine of AMBRE. The insertion system developed is, at the state of the art, the first system allowing the use of hybrid autophage technology in flight. This paper highlights the advancements made in the development of AMBRE towards its first experimental launch and the research and development roadmap ahead. The project will prove the concept of hybrid autophage propulsion, paving the way for a larger scale orbital prototype.