There are four main types of airplane flaps found on aircraft. The purpose of an airplane flap is to change the aerodynamic shape, or camber, of a wing. Flaps increase an aircraft's drag while increasing its ability to produce lift, therefore allowing the aircraft to prepare for takeoff and landing. Airplane flaps are normally found on the inboard section of a wing's trailing edge.
- Slotted flap. The slotted flap is the type of airplane flap found on small piston engine aircraft. Most two- and four-seat modern aircraft are equipped with slotted flaps. Slotted flaps feature a small crack in between the wing and the flap surface, allowing a bit of air to travel from under the wing to the top of the flap. This process "recharges" the air over the top of the flap, helping to prevent an aerodynamic stall.
- Fowler flap. The Fowler flap is the type of airplane flap found on most jet aircraft. Fowler flaps are embedded in the wing, allowing for a minimal amount of drag while the aircraft is in cruise flight, a critical feature for a high-speed jet.
- Plain flap. Plain flaps are a type of airplane flap featured on most older model aircraft. They use a simple flap, often powered by a cable controlled by the pilot, that pivots downward, creating an increase of lift and drag.
- Split flap. A rather dated style of flap, split flaps are found on older aircraft, such as World War II-era fighters. Split flaps are hinged several inches forward on a wing's trailing edge. When extended, the top of the aircraft's wing maintains its original shape.