What is the angle of attack?

The angle of attack is defined as the angle between the chord line of the wing and the relative wind. This measurement is crucial because it directly affects the lift generated by the wing. When the angle of attack increases, more lift is created up to a certain point, known as the critical angle of attack, beyond which the wing may stall. Understanding this relationship is fundamental for pilots, as it helps them control the aircraft’s performance, particularly during takeoff and landing phases.

The other options do not accurately describe the angle of attack. For instance, the angle between the wing and the fuselage pertains more to aircraft design and alignment, while the angle between the flight path and the horizon refers to the aircraft's pitch attitude rather than the aerodynamic relationship necessary to generate lift. Similarly, the angle between the flaps and the wing relates to the position of the flaps, which affect lift and drag but are not the defining characteristic of angle of attack itself. Therefore, recognizing that the angle of attack specifically involves the wing’s chord line and the relative wind is essential for a solid understanding of aerodynamic principles.