The University of Michigan researchers have developed an interactive tool to address the challenge of sustainable aviation and the efficient utilization of renewable energy for flying aircraft. Led by Joaquim Martins and Eytan Adler, the team explored various propulsion systems, including e-SAF, battery-electric, hydrogen fuel cell, and hydrogen combustion, to determine the most energy-efficient option for different flight scenarios. The tool allows users to compare the energy consumption and sustainability of these systems, considering factors like range, speed, and energy requirements. Efficiency, defined as the renewable electricity needed to produce fuel for a specific mission, is a critical aspect of the study. Currently, fuel costs make up a significant portion of airlines' operating expenses, especially for long-haul flights. The research highlights that hydrogen fuel emerges as the most efficient option for longer flights due to its lightweight properties, despite the lower efficiency of producing hydrogen using electricity. The tool also addresses the limitations and potential improvements of current technologies, such as battery storage capacity and hydrogen storage. It explores how enhancing these technologies can impact the efficiency and range of sustainable aviation solutions. Furthermore, it compares the properties and performance of different propulsion systems, including fuel cells and combustion engines, for varying flight conditions. The study emphasizes the importance of sustainability, cost-effectiveness, and technological advancements in shaping the future of aviation. By providing a platform to compare and evolve ideas, the interactive tool serves as a valuable resource for researchers and industry professionals working towards carbon-neutral aviation solutions.