A conceptual design of a commercial 154-passenger electric aircraft was investigated, focusing on renewable fuels to supply efficient, high-temperature, solid oxide fuel cells (SOFCs). Hybrid SOFCs were integrated with turbine-electric propulsion and batteries to power the aircraft, with the goal of addressing the current range limitations of electric aviation. The concept matched the range and the comparable payload capabilities of a B737-800 while using two-thirds less fuel on a 3000-mile mission. The aircraft featured a NASA/Boeing truss-braced wing design, selected for its high-wing configuration, a 10% improvement in aerodynamic efficiency, and compatibility with open fans that offered 13% higher propulsive efficiency. Renewable liquid natural gas (LNG) fuel was chosen for its ease of fuel reformation, potentially higher availability, and lower cost than sustainable aviation fuel. Additionally, LNG is safer and easier to use than LH2 or ammonia fuels and will enable safe, wing-mounted fuel tanks. Although many of these technologies can likely be implemented before aviation SOFCs fully mature, they will further reduce operating costs while utilizing a smaller volume of carbon-neutral fuel. This configuration also has the potential to capture and divert exhaust water vapor, reducing the formation of persistent contrails that are believed to nearly double the environmental impact of traditional aircraft.
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