The Wright brothers built a wind tunnel to measure wing performance in 1901.
After disappointing results from their 1901 glider, the brothers questioned published aerodynamic data. They constructed a small wind tunnel in their Dayton bicycle shop and tested more than 200 wing shapes. Their work compared lift and drag, two central forces in aircraft design.
The experiments helped the brothers correct inaccurate assumptions about airfoil behavior. They used the improved data to design the 1902 glider, which had more effective wings and a workable three-axis control system.
The wind tunnel was a major step because it let the brothers study aerodynamic shapes under controlled conditions instead of relying only on outdoor gliding trials. Their bicycle-building experience also helped them make precise measuring devices and practical test equipment.