Axes of Rotation
An aircraft has three axes of rotation: vertical, lateral, and longitudinal.
Credits - Civil Air Patrol
In addition to moving forward, aircraft move about three axes in response to three forces: lift, drag, and side force. These axes can be visualized as three rods that pass through the aircraft so that each intersects the other two. The point of intersection is called the center of gravity. Each of these axes is also perpendicular to the other two.
The axis that extends lengthwise through the nose and tail is called the longitudinal axis. Rotation about this axis is called roll. Drag is the force that acts along this axis, but in the opposite direction of the flight path.
The axis that extends crosswise from wingtip to wingtip is called the lateral axis. Rotation about this axis is called pitch. Side force acts along this axis.
The axis that passes vertically through the center of gravity when the aircraft is in level flight is called the vertical axis. Rotation about this axis is called yaw. Lift acts along this axis.
Movement of the ailerons produces changes in roll. Movements of the rudder produce changes in yaw. Movements of the elevator cause changes in pitch.