CG Limits

The primary concern in balancing an aircraft is the fore and aft location of the CG along the longitudinal axis. The CG is not necessarily a fixed point; its location depends on the distribution of weight in the aircraft. As variable load items are shifted or expended, there is a resultant shift in CG location. The distance between the forward and back limits for the position of the center for gravity or CG range is certified for an aircraft by the manufacturer. The pilot should realize that if the CG is displaced too far forward on the longitudinal axis, a nose-heavy condition will result, preventing an aircraft from even rotating during the takeoff roll. Conversely, if the CG is displaced too far aft along the longitudinal axis, a tail heavy condition results, which may prevent an aircraft from recovering from a stalled condition. It is also important to understand that the location of the CG has a significant effect on maneuverability and performance. The following discussion holds true provided that the CG still remains with the acceptable limits prescribed by the manufacturer.

A rearward CG will result in the following conditions:

  • Improved fuel performance and range along with reduced drag due to a smaller tail down-force
  • Poorer stall recovery characteristics due to a smaller nose-down moment and reduced longitudinal stability
  • Lower stall speeds due to a smaller tail down-force 
  • Higher true airspeed at any given power setting

A forward CG will result in the following conditions:

  • Improved longitudinal stability and stall recovery characteristics due to a larger nose-down moment
  • Reduced range and poorer fuel performance due to increased drag created by a larger tail down-force
  • Increased stall speed resulting from the higher tail down-force
  • Lower true airspeed at any given power setting