To initiate and turn the aircraft, the pilot’s primary action is to bank the plane; the airplane enters a banked attitude due to the deflection of the ailerons. If the pilot wants to initiate a bank to the right, as is shown in the figure on the left, the aileron of the left wing will move downwards, thereby producing more lift and lifting the left wing up. Simultaneously, the aileron of the right wing moves up, to decrease the right wing’s lifting capability.
The overall effect is for the plane to roll towards the right. However, for an efficient turn, the pilots must use three other controls. Don’t forget that it is not the rudder that turns the airplane, but the horizontal component of lift. The ailerons (wing flaps) are positioned to create the required horizontal component of lift whereas the rudders help coordinate the turn.
The Role of Elevators in Airplane Turns
The primary effect of banking an aircraft is the division of total lift into vertical and horizontal components. This interprets into a lesser amount of lift force countering the gravitational force of Earth and hence supporting the weight of the aircraft.
As a result, the airplane does turn, but also loses its altitude since a portion of the lift force is now being used to turn the airplane. The greater the bank angle is, the greater the loss of lift (vertical component).
To correct for this, and avoid losing altitude, the pilot must increase the angle of attack; increasing the total lift force produced by the wings of the aircraft.
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