AFOQT Practice Test

Which axis does roll control along in an aircraft?

1. Longitudinal axis

2. Vertical axis

3. Transverse axis

4. Horizontal axis

The correct answer is: Longitudinal axis

Roll control in an aircraft occurs along the longitudinal axis, which runs from the nose to the tail of the aircraft. This axis is pivotal in determining the aircraft's rotation about its longitudinal length, facilitating the banking movement during turns. Ailerons, which are control surfaces located on the wings, are primarily responsible for creating differential lift, thus allowing for this roll motion. When one aileron is raised, it decreases lift on that wing, while lowering the opposite aileron increases lift on the other wing. This differential results in the aircraft rolling to one side. The other axes listed do not pertain to roll control: the vertical axis is related to yaw (rotation about the vertical line through the center of the aircraft), the transverse axis is associated with pitch (rotation about the line extending from wingtip to wingtip), and the horizontal axis doesn’t accurately describe the key reference lines used in aviation to denote the movements of an aircraft.