In a climb, the ascending blade has a reduced angle of attack.

• A. Increased
• B. Decreased
• C. Unchanged
• D. Reduced

Answer: (D)

Angle of attack is set by the direction of the relative wind the blade meets versus the blade’s pitch. In a climb, the aircraft’s flight path has an upward component, and the rotor must produce more thrust, which increases the downward air through the rotor (induced flow). For the blade that is moving upward (the ascending blade), this combination tilts the relative wind so that it meets the blade at a smaller angle to the chord. In short, the upward-moving blade encounters air at a direction that reduces the angle between the blade’s chord and the relative wind, so its angle of attack decreases. The other options don’t fit because the geometric and flow changes in a climb do produce this reduction, not an increase or an unchanged angle.