An Historical and Applied Aerodynamic Study of the Wright Brothers’ Wind Tunnel Test Program and Application to Successful Manned Flight

A replica wind tunnel was built and used to test the flow quality through the Wright Brothers’ wind tunnel. The research determined the effect flow quality and experimental method had on the Brothers’ results, and whether those results were useful in a quantitative sense. Particle image velocimetry revealed boundary layers extending 2.5” (63.5 mm) from each wall, and velocity gradients as large as 20% along the wind tunnel model span resulting in an asymmetric lift distribution. Similarly, the balance generated asymmetric wingtip vortices contributing to asymmetric downwash along the span of the model. Direct force measurements of a replica of the Wrights #12 airfoil showed their lift measurements were at least 7% and as much as 15% too low, and numerical analysis revealed wind tunnel predictions for lift, drag, and efficiency were not applicable to full scale design due to Reynolds number scaling effects.