Preliminary Aero-Elastic Optimization of a Twin-Aisle Long-Haul Aircraft with Increased Aspect Ratio

This paper presents a preliminary study on the improvement of the fuel efficiency of a civil transport aircraft, focusing on the aero-elastic optimization of an increased aspect ratio wingbox. The wing is stretched, increasing its aspect ratio, and a trade-off between the improved aerodynamic efficiency and the structural mass identifies an optimal aspect ratio for such aircraft. The aeroelastic optimization is performed with NeOPT, a structural optimizer for conceptual and preliminary design phases. The analysis considers different materials and structural solutions for the wingbox and tackles aeroelastic constraints, such as flutter and aileron efficiency, from the preliminary design phases. The fuel consumption of the sized aircraft is evaluated with a simplified approach that provides an indication of the fuel efficiency. The results show how a composite wing with increased aspect ratio can save up to 6.9% of fuel burnt with respect to the baseline aluminum wing. The results are extended at fleet level, achieving a 2-million-ton cut in CO2 emissions and a saving of USD 1.28 million on fuel-related costs.