Slats and flaps are both high-lift devices.

• A. False
• B. True
• C. Only slats are high-lift
• D. Only flaps are high-lift

Answer: (B)

High-lift devices are used to generate more lift at lower speeds by changing the wing’s shape and how the air flows over it. Slats are leading-edge devices that extend to create a slot or smoother airflow to the upper surface, energizing the boundary layer and delaying stall. Flaps are trailing-edge devices that extend to increase wing camber and, in many designs, wing area as they move rearward, producing a big boost in lift for takeoff and landing. Because both slats and flaps serve this purpose, the statement is true. The other options would imply that one or neither of these devices provides high lift, which isn’t the case.