FAA Ground School Practice Test

What is the relationship of the angle between the chord line of an airfoil and the relative wind referred to?

1. Aspect ratio

2. Angle of attack

3. Static margin

4. Drag coefficient

The correct answer is: Angle of attack

The angle between the chord line of an airfoil and the relative wind is known as the angle of attack. This angle is crucial in aerodynamics as it directly affects the lift generated by the airfoil and its overall performance. When the angle of attack increases, the lift increases up to a certain point, beyond which stall may occur. This relationship is fundamental in the study of flight dynamics and is a key factor pilots consider when managing aircraft performance and control. In contrast, aspect ratio refers to the ratio of the wingspan to the average wing width and is primarily used to describe the geometry of wings. Static margin concerns the stability of an aircraft and refers to the distance between the center of gravity and the aerodynamic center of the aircraft. The drag coefficient is a dimensionless number that describes the drag force relative to the dynamic pressure of the fluid around the object, but it does not specifically pertain to the angle between the chord line and the relative wind. Understanding the angle of attack and its implications is vital for safe and effective flying.