Control surfaces are the moving parts of an airplane that adjust the itspath flight. There
are several control services that have been standardized and used in most commercial , civil
and military aircraft. These surfaces are the ailerons, flaps, elevators, rudder and trim tab.
Ailerons: Ailerons are the control surfaces that are located on the trailing
edge of the wing. They serve the purpose of adjusting the roll of
the airplane. The two ailerons move in opposite directions. They
also are used to turn the airplane, although unless rudder is added
the turn will be sloppy.
Flaps: Flaps are located to the inner trailing edge of the wing. These serve
two purposes, one is to increase drag and slow the plane, the other is
to increase the lift produced by the wing. The flaps are used in landing
and sometimes takeoff. In landing the flaps allow a aircraft to make a
steeper descent without gaining to much speed and fly more slowly while
producing the same amount of lift. In takeoff the flaps are sometimes
used to shorten the necessary takeoff distance.
Rudder: The Rudder is located on the trailing edge of the vertical stabilizer. It
is used to control the yaw or left right motion of a plane. The rudder is
primarily used to turn the plane but to make a clean turn you need to use
both the rudder and the ailerons. The rudder is also used to help a plane
taxi on the ground.
Elevator: The elevators are used to control the planes pitch or up down motion.
They are located on the trailing edge of the horizontal stabilizers. The
elevators are used to make a plane climb and descend. On the elevators
and some of the rudders of aircraft there are located trim tabs. These
are tabs that can be adjusted to relieve pressure off the controls.
Spoilers:The spoiler of an aircraft is used to slow the
plane down on landing. This feature is usually seen only on the larger
and the jet powered planes. Generally small planes such as the Cessna 172
do not have spoilers.
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