The Effect of Wing Stiffness and Centre of Gravity on the Glide Performance of Paper Airplanes

Abstract

This study investigates how wing stiffness and center of gravity (CG) affect the glide performance of paper airplanes, which serve as simplified physical models for micro air vehicles (MAVs) operating at low Reynolds numbers. To examine these effects, three distinct wing stiffness levels and two CG positions were tested across 29 indoor free-flight trials. Each flight was recorded and analyzed using Tracker software to measure glide ratio, glide angle, and flight stability. The results revealed that a forward CG consistently enhanced stability, helping to prevent pitching oscillations and erratic descents. Increased wing stiffness contributed to more predictable and repeatable flight paths, yet did not necessarily improve glide efficiency, highlighting that rigidity alone cannot guarantee better aerodynamic performance. Notably, the low-stiffness mid-CG configuration failed to produce any stable flights, underscoring the destabilizing interaction between flexible wings and aft CG. These findings emphasis the intrinsic trade-off between stability and efficiency in low-Reynolds-number flight. They offer valuable insights into MAV design, suggesting that careful balancing of structural flexibility and mass distribution is crucial for achieving both controlled flight and optimal glide performance.