This research focuses on optimizing PETG (Polyethylene Terephthalate Glycol) samples fabricated using Ultimaker 2+ Fusion Deposition Modeling (FDM), employing a desirability approach. PET's versatility in industries like Aeronautics, Astronautics, and Automotive relies on its strong mechanical and thermal properties. Challenges persist in achieving optimal print quality and mechanical performance. By systematically adjusting printing parameters like Print Speed (PS), Nozzle Temperature (NT), Wall Thickness (WT) and Infill Density (ID), this study aims to enhance PET sample quality. Evaluating their impact on performance characteristics Tensile Strength (TS) and Surface Roughness (SR) provides insights for wider adoption in Aerospace applications.