What is defined as the angle between the chord line of the wing and the relative wind?

The angle between the chord line of the wing and the relative wind is known as the angle of attack. This angle plays a critical role in the aerodynamics of flight, as it directly influences lift generation. When the angle of attack increases, the lift produced by the wing also increases, up until a certain point known as the critical angle of attack, beyond which the wing may stall.

The chord line is an imaginary line that extends from the leading edge to the trailing edge of the wing, while the relative wind is the airflow encountered by the wing as the aircraft moves through the air. Understanding the angle of attack is essential for pilots and engineers because it helps in managing the aircraft's performance and stability during flight.

Other angles, such as the angle of incidence, refer to the fixed angle at which the wing is attached to the fuselage, while yaw pertains to the movement of the aircraft around its vertical axis. Pitch describes the angle of the aircraft's nose relative to the horizon but does not specifically address the relationship between the wing and airflow. Therefore, the angle of attack is the term that accurately captures the relationship between the chord line of the wing and the relative wind.