A split flap increases:

A split flap increases:

• A. Camber and nose-down pitching moment
• B. Chord and camber and nose-up pitching moment
• C. Wing area and nose-down pitching moment
• D. Increases lift and reduces drag

Answer: (A)

A split flap mainly changes the wing shape by increasing camber. By deflecting a portion of the lower surface downward, the airfoil becomes more curved, which raises the lift obtainable at a given angle of attack. This camber increase also shifts the distribution of lift in such a way that, for typical configurations, the resultant aerodynamic force causes a nose-down pitching moment when the flap is extended. The effect is not about increasing chord or wing area, and in practice flaps add drag as they increase lift, so they do not reduce drag.

A split flap mainly changes the wing shape by increasing camber. By deflecting a portion of the lower surface downward, the airfoil becomes more curved, which raises the lift obtainable at a given angle of attack. This camber increase also shifts the distribution of lift in such a way that, for typical configurations, the resultant aerodynamic force causes a nose-down pitching moment when the flap is extended. The effect is not about increasing chord or wing area, and in practice flaps add drag as they increase lift, so they do not reduce drag.