What is the purpose of slats on an aircraft wing?

Slats on an aircraft wing are designed primarily to prevent boundary layer separation. When an aircraft operates at lower speeds, particularly during takeoff and landing, the airflow over the wing can become disrupted, leading to separation of the boundary layer. This separation can cause a significant reduction in lift and possibly result in stalls.

By incorporating slats, manufacturers enhance the wing's aerodynamic performance by allowing the airflow to remain attached to the wing surface longer. Slats extend the camber of the wing and increase the effective wing area, improving lift characteristics at lower speeds. This is critical for maintaining controlled flight during the phases of flight where the aircraft is most likely to encounter slower speeds and higher angles of attack.

The other options do not accurately reflect the primary function of slats. Increasing drag during landing can be a side effect, but it's not their purpose. Decreasing lift at low speeds contradicts the role of slats, which is to increase lift. Additionally, reducing fuel consumption is not a direct role of slats but may be a secondary benefit from improved aerodynamic efficiency.