Undergraduate Aeroelasticity: The Typical Section Idealization Re-Examined

A simple typical section approach to aircraft wing bending-torsion divergence and flutter is presented. The approach can be used to illustrate the significant effects of wing sweep and material orthotropy in response to either steady or a simplified unsteady aerodynamic loading. This paper proposes that the typical section model, despite its well known deficiencies as a predictive tool, is appropriate as a learning device at the undergraduate level. The influences of wing sweep, material orthotropy and aerodynamic damping can be sequentially introduced with the aid of a single model. Indeed, the typical section approach outlined herein can be the unifying model that complements existing textbook presentations. Divergence and flutter velocities for a graphite-epoxy wing configuration are shown; the solution spans all angles of sweep and fiber orientations. Further, the approach is implemented in an MS Excel spreadsheet. The graphical user interface uses a notional wing geometry to aid in illustration and visualization during class or during individual study. The velocity root locus is plotted in real time based on 13 user inputs.