A consortium comprising Fraunhofer IWS, the TUD Dresden University of Technology, ArianeGroup, and the Warsaw Institute of Aviation has achieved a significant breakthrough in aerospace engineering: the first successful hot gas test of a 3D-printed aerospike engine powered by a combination of sustainable hydrogen peroxide and kerosene propellant. This project was conducted under the ESA-funded ASPIRER initiative. The test results hold the potential to enhance the efficiency of space missions significantly.