Eco-design vision for reusable vertical launch vehicles supported by multi-disciplinary design methodology and framework

In recent decades, the introduction of reusable launch vehicles (RLVs) has revolutionised the space sector, demonstrating technical operational feasibility and enabling a significant reduction in launch costs. This work presents an extension of a methodology originally developed for expendable micro-launchers, making it suitable for reusable launcher prototyping of various sizes and aligning it with a new vision of sustainable design: ecodesign. Three main enhancements have been introduced: (i) a statistical module integrated into the design workflow; (ii) a mission analysis module adapted to include descent consumption and reusability features; (iii) the capability to size the propulsion system and estimate corresponding emissions along trajectory. The methodology has been implemented within a modular, multi-fidelity framework that enables rapid iteration from high-level design and mission requirements, generating estimates of size, mass, performance, and mission profile. Subsystem interactions are handled through data exchange between modules ensuring consistent preliminary sizing and evaluation of each subsystem's impact. In support of sustainability goals, a module for estimating pollutant and greenhouse gas emissions has been integrated from the early stages of conceptual design. The framework has been tested using a partially reusable Two-Stage-To-Orbit (TSTO) Vertical Take-Off Vertical Landing (VTVL) configuration, with the European prototype RETALT1 as a reference. Validation using ASTOS software confirmed the accuracy of the mission module and enabled optimisation of ascent and descent trajectories. The framework's ability to deliver design results in minutes and visualise mass and budget breakdowns facilitates informed decision-making in early design stages. Emission analysis further supports eco-design strategies for future space vehicles.