What happens to the air flow when a slotted flap is deployed?

When a slotted flap is deployed, it specifically functions to enhance the airflow characteristics over the wing by allowing high-pressure air to flow over the wing surface. This mechanism is essential in improving the lift produced by the wing, especially during critical phases of flight such as takeoff and landing.

The deployment of slotted flaps increases the effective wing area, and the slots provide a pathway for the high-energy air from the high-pressure region below the wing to mix with the lower pressure air above the wing. This mixing helps to delay airflow separation, allowing the wing to maintain lift at higher angles of attack, which is advantageous for achieving better performance during slower speeds when the aircraft is approaching or departing from the runway.

As a result, the primary purpose of slotted flaps is to enhance lift and improve the overall performance of the aircraft during these phases of flight.