Question

Which of the following is a new NACA airfoil?

(a) NACA 2212

(b) NACA LS (1)-0407

(c) NACA 0021

(d) Both NACA LS (1)-0407 and NACA 2412

I had been asked this question in an interview for internship.

Query is from Modern Low Speed Airfoils topic in portion Incompressible Flow over Airfoils of Aerodynamics

Answer 1

The correct option is (b) NACA LS (1)-0407

The best explanation: The new airfoils are the low-speed airfoils (designated by LS). So NACA LS (1)-04XX are the new airfoils while the NACA XXXX are the standard airfoils.