"An airfoil is an important component in any aircraft to help the craft takeoff or make elevation changes while in flight. On airplanes, they are most common on the wing section. The basic principle is that as the airfoil is inclined, the airflow coming at the aircraft produces both lift and drag that help the aircraft climb in the air. In theory, the great the inclination means the more lift. But, basic physics principles such as friction can cause air stalls if the inclination is too high on the airfoil. In basic design principles, slower aircraft that generally carry heavier loads utilize thick airfoils that produce a high amount of life and drag. Conversely, high speed aircraft utilize very thin airfoils for lower drag and lower lift."