What function does a slat serve when deployed on an aircraft wing?

When deployed on an aircraft wing, a slat serves to create a new wing configuration that allows for a higher angle of attack. This is crucial for maintaining lift at lower airspeeds, particularly during critical phases of flight such as takeoff and landing.

Slats are designed to enhance airflow over the wing's upper surface, thereby delaying flow separation and allowing the wing to remain effective at higher angles of attack than it would without the slats. This is particularly beneficial because as the aircraft slows down, it approaches a stall condition. By effectively reconfiguring the wing, the slats enable pilots to operate safely at speeds closer to stall.

In contrast, the functions of increasing drag for landing and reducing fuel consumption are not primary roles of slats; they are more related to other aerodynamic components or strategies. Decreasing lift at low speeds is also incorrect, as slats are specifically intended to enhance lift in that operational regime. Thus, the action of the slats allows for safer flight with improved aerodynamic performance.