The angle of attack is defined as the angle between which two lines?

• A. Between the wing leading edge and the relative wind
• B. Between the wing trailing edge and the relative wind
• C. Between the wing chord line and the relative wind
• D. Between the fuselage and the relative wind

Answer: (C)

The angle of attack is the angle between the wing's chord line and the relative wind. The relative wind is the airflow direction at the aircraft as it moves through the air (opposite to the direction of motion), and the chord line is a straight line from the wing’s leading edge to its trailing edge. So, AoA measures how tilted the wing is relative to the oncoming air, which directly affects lift and stall behavior. The other options don’t describe AoA: it’s not the angle to the leading or trailing edge individually, and it’s not the angle between the fuselage and the wind.