Question

The major breakthrough in high- speed airfoil industry was_____

(a) GA (W)-1 airfoil

(b) Supercritical airfoil

(c) Standard NACA airfoils

(d) Symmetrical airfoils

The question was posed to me in a job interview.

This interesting question is from Modern Low Speed Airfoils in portion Incompressible Flow over Airfoils of Aerodynamics

Answer 1

Correct choice is (b) Supercritical airfoil

The explanation is: The GA (W)-1 (also known as Whitcomb airfoil) airfoil was the first low-speed airfoil obtained under the new airfoils. It led to the development of supercritical airfoils which had an almost similar shape. The supercritical airfoils had lesser drag at high subsonic speeds, which was a major performance improvement.