16 / 24
2
BOB TAIT'S AVIATION THEORY SCHOOL CPL AERODYNAMICS
An aircraft is capable of three types of motion. It can pitch, roll and yaw. When an aircraft moves in the manner
shown in Fig 1.1, it is pitching. In Fig 1.1[a] the nose is rising and the tail is dropping. All of the points forward
of the axis are moving upwards and all of the points aft of the axis are moving downwards. The axis is the point
about which the motion is occurring and is referred to as the lateral axis. In Fig 1.1[b] the aircraft is pitching nose
down about the lateral axis.
Fig 1.1[c]
Fig 1.1[a]
Fig 1.1[b]
When an aircraft moves in the manner shown in Fig 1.2 it is rolling. In Fig1.2[a] the roll is to the left. The left
wing is dropping and the right wing is rising. All of the points to the left of the axis are moving downwards, while
all of the points to the right of the axis are moving upwards. The axis is the point about which the motion is oc-
curring and in this case is referred to as the longitudinal axis. The aircraft in Fig 1.2[b] is rolling to the right about
the longitudinal axis.
Fig 1.2 [a]
Fig 1.2 [b]
Fig 1.2 [c]
axis
axis
Nose-up pitch
Nose-down pitch
lateral axis
lateral axis
Rolling right
Right wing
drops
Left wing
rises
Rolling left
Right
wing rises
Left wing
drops
longitudinal
longitudinal
axis
axis
PART 1 - AIRCRAFT MOTION