Which feature is primarily enhanced by an all-moving tailplane?

An all-moving tailplane, also known as a stabilator, enhances elevator control authority because it acts as both a stabilizer and an elevator. This design allows the entire tailplane to move up and down to control pitch, providing pilots with a greater range of control over the aircraft's attitude. Unlike traditional fixed horizontal stabilizers with separate elevators, an all-moving tailplane can produce more lift and a more significant change in pitch due to its larger control surface area and more effective aerodynamic design.

Enhanced elevator control authority is critical during various flight phases, such as take-off and landing, where precise pitch control is necessary to maintain optimal flight safety and performance. The effectiveness of an all-moving tailplane can lead to a more responsive handling characteristic and improved performance metrics for the aircraft overall.