Which axis is primarily of concern for the 'Center of Gravity' (CG)?

The Center of Gravity (CG) is primarily concerned with the longitudinal axis of an aircraft, which runs from the nose to the tail. The location of the CG along this axis directly affects the aircraft's stability and control during flight. When the CG is positioned correctly along the longitudinal axis, it ensures that the aircraft maintains a proper balance and control characteristics. If the CG is too far forward or too far aft along this axis, it can lead to handling issues such as excessive nose-up or nose-down attitudes, which can compromise safety and performance.

In aircraft design and operation, careful consideration of the CG along the longitudinal axis is crucial for achieving optimal performance. This is why understanding its relationship with this axis is vital for A&P mechanics, who must ensure that loading and weight distributions are within limits to maintain favorable flight characteristics.