Wind-turbine-blade

grabcad

The series of airfoil shapes indicated are NACA4424, NACA4421 and NACA4418 in descending order of their complexity. These are all part of the NACA 4-digit series, where the first two digits represent the maximum camber height as a percentage of the chord length, and the last two digits indicate the position of maximum camber along the chord, also expressed in percentages of the chord length.