Forces Acting on an Airplane
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control movement about the longitudinal axis. The movement is roll. Lowering the aileron on one wing raises the aileron on the other.
The wing with the lowered aileron goes up because of its increased lift, and the wing with the raised aileron goes down because of its decreased lift. Thus, the effect of moving either aileron is aided by the simultaneous and opposite movement of the aileron on the other wing. Rods or cables connect the ailerons to each other and to the control wheel (or stick) in the cockpit.
When pressure is applied to the right on the control wheel, the left aileron goes down and the right aileron goes up, rolling the airplane to the right. This happens because the down movement of the left aileron increases the wing camber (curvature) and thus increases the angle of attack. The right aileron moves upward and decreases the camber, resulting in a decreased angle of attack.
Thus, decreased lift on the right wing and increased lift on the left wing cause a roll and bank to the right. Elevators: The elevators control the movement of the airplane about its lateral axis. This motion is pitch.
The elevators form the rear part of the horizontal tail assembly and are free to swing up and down. They are hinged to a fixed surface the horizontal stabilizer. Together, the horizontal stabilizer and the elevators form a single airfoil.
A change in position of the elevators modifies the camber of the airfoil, which increases or decreases lift. Like the ailerons, the elevators are connected to the control wheel (or stick) by control cables. When forward pressure is applied on the wheel, the elevators move downward.
This increases the lift produced by the horizontal tail surfaces.Скачать