What effect does having the centre of gravity aft have on take-off ground roll distance?

Having the centre of gravity positioned aft impacts the take-off ground roll distance by decreasing it. When the centre of gravity moves toward the tail of the aircraft, the aerodynamic lift contribution during the take-off roll increases. This can lead to an earlier rotation and take-off, as the aircraft becomes more responsive to control inputs. The reduced distance required to achieve the necessary speed for liftoff is attributed to improved aerodynamic efficiency, allowing the aircraft to generate sufficient lift more quickly.

This phenomenon can be particularly beneficial in certain operational scenarios, where a shorter runway is essential or in achieving optimal performance during take-off. However, it's important to note that having an excessively aft centre of gravity can lead to challenges during flight phases, particularly affecting stability and control, making balance a critical factor for safe operations.