Which aspect of their design was crucial for maneuverability during flight?

The three-axis control system was essential for maneuverability during flight, as it provided pilots with independent control over the aircraft's pitch, roll, and yaw. This system allowed for precise adjustments in the aircraft's orientation and direction, enabling pilots to navigate effectively and respond to changes in the flight environment. By managing these three axes, pilots could perform a variety of maneuvers, enhancing the aircraft's ability to turn, climb, or descend smoothly, which is vital for effective control and safety during flight.

While elements such as a lightweight structure, the use of ailerons, and a powerful engine can contribute to overall performance and handling characteristics, the capability to directly manipulate all three axes of flight is what fundamentally allows pilots to achieve greater control and maneuverability. Thus, the three-axis control system stands out as a key factor in ensuring that the aircraft could perform diverse movements with precision.