What is the angle at which the chord of an aircraft's wing meets the relative wind?

• A. Angle of attack
• B. Downwash
• C. Relative wind
• D. Upwash

Answer: (A)

The angle at which the wing meets the oncoming air is the angle of attack. It is defined as the angle between the wing’s chord line (the straight line from the leading edge to the trailing edge) and the relative wind, which is the direction the air is moving relative to the wing (opposite to the aircraft’s motion). This angle governs how much lift is generated—the higher the angle up to a point, the more lift, until stall occurs. Downwash and upwash describe how the air is deflected by the wing in its wake, not the angle between the wing and the wind. Relative wind is the direction of the incoming air, involved in defining the angle, but it is not the angle itself.