What does the thickness of a wing refer to?

The thickness of a wing refers specifically to the maximum difference in distance between the upper and lower surfaces. This measurement is crucial in aerodynamic design, as it significantly impacts the wing's lift characteristics and overall performance. A thicker wing may generate more lift at lower speeds because it has more surface area and could have better airflow characteristics, yet it can also increase drag.

Understanding this concept is essential for pilots and engineers, as wing thickness affects not just lift, but also stall characteristics and the wing's structural capabilities. While other options mention different aspects of the wing's dimensions or characteristics, none address the specific definition of thickness as it pertains to the maximum distance between the upper and lower surfaces.