How Are the Control Surfaces of an Airplane Used for a Level Turn?

An aircraft's control surfaces work with forces pushing on the aircraft to turn a plane.

Airplanes use the differential between air pressures above and below the wings to stay in the air; this is called "lift." When an airplane makes a turn --- called "banking" --- the pilot uses various control surfaces to keep the aircraft's turn level.

Basic Physics

The higher air pressure rushing under the wing creates lift, holding the plane in the air, perpendicular to the direction of flight. A side force acts on the fuselage of the plane, perpendicular to the direction of flight, while the plane is banking.

The Ailerons

An aircraft's ailerons are control surfaces on the plane's wing, alongside the plane's flaps. The pilots use the stick in the cockpit to roll one aileron down and the other up; this causes the plane to roll to one side or the other. When one aileron is lifted, the plane banks to the opposite side.

The Rudder

An aircraft's rudder is the vertical-facing flap on the plane's tail. The rudder is controlled by the pilots using pedals in the cockpit. When the rudder is angled to the left, the plane's nose banks slightly to the left, and vice-versa. The motion of the rudder keeps the plane's nose from lifting or falling during banking.

References

• Aviastar: Basics of Flight
• Aviastar: Basic Flight Maneuvers
• NASA: Glenn Research Center: Banking Turns