The two basic types of airfoils are:

The two basic types of airfoils are:

• A. Symmetrical
• B. Nonsymmetrical (cambered)
• C. Symmetrical and nonsymmetrical (cambered)
• D. Elliptical

Answer: (C)

Airfoils are most commonly classified by camber. There are two broad categories: symmetric, which has zero camber and identical curvature on top and bottom, and nonsymmetric or cambered, which has curvature that favors lift and is not identical on both sides. This distinction matters because cambered airfoils generate lift more readily and at smaller angles of attack, while symmetric airfoils rely more on the angle of attack to produce lift and have a neutral zero-lift angle. The option that lists both symmetric and cambered as the two basic types correctly captures this fundamental classification. The other choices point to either one type only or to a specific shape (elliptical) rather than the general categories by camber.

Airfoils are most commonly classified by camber. There are two broad categories: symmetric, which has zero camber and identical curvature on top and bottom, and nonsymmetric or cambered, which has curvature that favors lift and is not identical on both sides. This distinction matters because cambered airfoils generate lift more readily and at smaller angles of attack, while symmetric airfoils rely more on the angle of attack to produce lift and have a neutral zero-lift angle.

The option that lists both symmetric and cambered as the two basic types correctly captures this fundamental classification. The other choices point to either one type only or to a specific shape (elliptical) rather than the general categories by camber.