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CPL AERODYNAMICS ALL RIGHTS RESERVED © 2014
3
When an aircraft moves in the manner shown in Fig 1.3 [a,b,&c] it is yawing. In Fig 1.3[a] the nose is moving to
the left and the tail is moving to the right. All points in front of the axis are moving to the left, while all points aft
of the axis are moving to the right. The axis is the point about which the motion is occurring and is referred to as
the normal axis. Some old text books may refer to the normal axis as the vertical axis. The aircraft in Fig 1.3[b]
is yawing to the right about the normal axis.
Fig 1.3[a]
Fig 1.3[b]
Fig 1.3[c]
Pitching, rolling and yawing are not unique to aeroplanes. All three dimensional objects in the universe are capable
of pitch, roll and yaw. The point that is often missed is that there is no other type of motion possible. The most
complicated aerobatic manoeuvre ever devised is simply various degrees of pitch, roll and yaw - maybe all three
simultaneously - but still only pitch, roll and yaw. If we can initiate or prevent movement in pitch, roll and yaw,
we can be certain that we will always have complete control of the aeroplane since no other motion is possible.
axis
axis
yaw left
yaw right
normal axis