In this case, there is a 4% maximum camber at 40% of the chord length from the leading edge. The first two digits describe the magnitude and placement of the camber, respectively. Let’s use the NACA 4412 airfoil as an example. Each digit describes a different parameter of the airfoil. The NACA four-digit series provides a convenient way to demonstrate some additional airfoil parameters. If you were to draw a straight line from edge to edge, this would be called the chord line and its length is the chord length (or just “chord”). The front (or forward most part) is called the leading edge, while the back (or aft most part) is called the trailing edge. This provides large amounts of lift with minimal drag.
As you can see below, an airfoil typically has a thin, long profile. To start, let’s discuss the different parts of an airfoil. These and other important concepts will be discussed.
Relevant requirements may relate to stability, lift and drag characteristics, and manufacturability. As such, care should be taken to choose an airfoil that properly meets the performance requirements for your mission. The airfoil will play a large role in determining its aerodynamic performance characteristics and capabilities. Airfoil selection is one of the earliest and most important decisions made when desiging your UAV.