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BOB TAIT'S AVIATION THEORY SCHOOL CPL AERODYNAMICS
rudder [yaw]
elevator [pitch]
aileron [roll]
aileron [roll]
rolling plane
yawing plane
pitching plane
lateral axis
normal axis
longitudinal axis
Because of this, an aircraft requires only three primary flying controls. The elevator which initiates or prevents
motion in the pitching plane, the ailerons which initiate or prevent motion in the rolling plane and the rudder which
initiates or prevents motion in the yawing plane.
Fig 1.5
Fig 1.4
All three axes intersect at a common point-the centre of gravity. In flight all motion in pitch, roll or yaw occurs
with the centre of gravity as the pivot. This again is not unique to aeroplanes, it is true of all objects that are free
to move in space. You will hear a great deal more about the centre of gravity when we consider aircraft stability
and control in detail later
.
longitudinal axis
normal axis
lateral axis
centre of gravity
Fig 1.6