Which factor has the least impact on the operational range of an RPAS?

The weight of the pilot has the least impact on the operational range of a remotely piloted aircraft system (RPAS). The operational range is primarily influenced by factors that directly affect the aircraft's performance, such as battery life, weather conditions, and signal interference.

Battery life is crucial, as it determines how long the aircraft can operate before needing to land for a recharge or battery replacement. Weather conditions can also significantly affect the range, as strong winds, rain, or other adverse weather can limit the aircraft's ability to travel and maintain stability. Signal interference, whether from other electronic devices or physical obstacles, affects the communication link between the pilot and the drone, potentially shortening the effective range of operation.

In contrast, the pilot's weight does not directly influence the aircraft’s range or performance because most RPAS operations do not involve the pilot being physically on board the aircraft. While the pilot's weight might be a consideration in other contexts, such as manned aircraft operations, it has negligible impact on a remotely piloted system, making this the correct choice in terms of minimizing influence on operational range.