Control Surfaces

Real planes have segments called ailerons inserted in the wings and segments called rudders and elevators inserted respectively in the vertical fin and horizontal stabilizer. The pilot controls their position from the airplane cockpit. When the pilot moves them into the airstream, they cause the plane to react to air pressure.The pilot uses them to go right or left and also up and down.

An airplane in flight changes direction by movement around one or more of its three axes of rotation: lateral axis, vertical axis, and longitudinal axis. These axes are imaginary lines that run perpendicularly to each other through the exact weight center of the airplane.
The airplane's rotation around them is called pitch, roll, and yaw. The pilot guides the airplane by controlling pitch, roll, and yaw, and by use of the elevators, ailerons, and rudder.

YAW
Rudder rotates the airplane around vertical axis.

ROLL
Ailerons rotate the airplane around longitudinal axis.

PITCH
Elevators rotate airplane around lateral axis.

What Makes An Airplane Fly

For an airplane to fly, it must always engage in a tug of war between the opposing forces of lift versus weight and thrust versus drag.

For a moment, think of an airplane moving from right to left and the flow of air moving from left to right. The weight or force due to gravity pulls down on the plane opposing the lift created by air flowing over the wing. Thrust is generated by the propeller and opposes drag caused by air resistance to the airplane. During take off, thrust must be greater than drag and lift must be greater than weight so that the airplane can become airborne.

For landing thrust must be less than drag, and lift must be less than weight.

THE FOUR FORCES ACTING ON AN AIRPLANE

An airplane in flight is the center of a continuous tug of war between four forces: lift, gravity force or weight, thrust, and drag. Lift and Drag are considered aerodynamic forces because they exist due to the movement of the aircraft through the air. The weight pulls down on the plane opposing the lift created by air flowing over the wing. Thrust is generated by the propeller and opposes drag caused by air resistance to the frontal area of the airplane. During take off, thrust must overcome drag and lift must overcome the weight before the airplane can become airborne. In level flight at constant speed, thrust exactly equals drag and lift exactly equals the weight or gravity force. For landings thrust must be reduced below the level of drag and lift below the level of the gravity force or weight

Lift

Lift is produced by a lower pressure created on the upper surface of an airplane's wing compared to the pressure on the wing's lower surface, causing the wing to be "lifted" upward. The special shape of the airplane wing (airfoil) is designed so that air flowing over it will have to travel a greater distance faster, resulting in a lower pressure area (see illustration) thus lifting the wing upward. Lift is that force which opposes the force of gravity (or weight).

Thrust

Thrust is a force created by a power source which gives an airplane forward motion. It can either "pull" or "push" an airplane forward. Thrust is that force which overcomes drag. Conventional airplanes utilize engines as well as propellers to obtain thrust.

Drag

Drag is the force which delays or slows the forward movement of an airplane through the air when the airflow direction is opposite to the direction of motion of the airplane. It is the friction of the air as it meets and passes over and about an airplane and its components. The more surface area exposed to rushing air, the greater the drag. An airplane's streamlined shape helps it pass through the air more easily.

Parts Of An Airplane

Control surfaces are the moveable outer surfaces of an airplane. These surfaces control the flow of air over the various sections of the aircraft causing it to move in different ways. Inside the airplane, pilots control the movement of the surfaces with their hands or feet by pushing, pulling or turning the controls to make the airplane move in the proper manner.

By learning the names and functions of the various surfaces, you will appreciate the construction, design, and aerodynamics of the airplane.

AIRPLANE
An airplane is a vehicle heavier than air, powered by an engine, which travels through the air by the reaction of air passing over its wings.

FUSELAGE
The fuselage is the central body portion of an airplane which accommodates the crew and passengers or cargo.

COCKPIT
In general aviation airplanes, the cockpit is usually the space in the fuselage for the pilot and the passengers: in some aircrafts it is just the pilot's compartment.

LANDING GEAR
The landing gear, located underneath the airplane, supports it while on the ground.

WINGS
Wings are the parts of airplanes which provide lift and support the entire weight of the aircraft and its contents while in flight.

PROPELLER
A propeller is a rotating blade located on the front of the airplane. The engine turns the propeller which most often pulls the airplane through the air.

FLAPS
Flaps are the movable sections of an airplane's wings closest to the fuselage. They are moved in the same direction (down) and enable the airplane to fly more slowly.

AILERONS
Ailerons are the outward movable sections of an airplane's wings which move in opposite directions (one up, one down). They are used in making turns.

RUDDER
The rudder is the movable vertical section of the tail which controls lateral movement.

HORIZONTAL STABILIZER
The horizontal stabilizer is the horizontal surface of the aft part of the fuselage used to balance the airplane.

ELEVATOR
The elevator is the movable horizontal section of the tail which causes the plane to move up and down.