What is a primary purpose of a rotating beacon at an airport?

The primary purpose of a rotating beacon at an airport is to mark the presence of the airport, especially when visibility is low. These beacons play a crucial role in enhancing safety by providing a visual signal to pilots flying in conditions where the airport may not be easily visible, such as at night or during inclement weather. The rotating light pattern helps distinguish the airport location from surrounding terrain and assists pilots in orientation as they approach for landing.

While the other options mention important aspects of airport operations, they do not capture the primary function of the rotating beacon. Communicating with aircraft, indicating fuel services, or informing pilots about weather conditions are indeed vital components of airport operations, but they are managed through different systems such as radio communication, signage, or dedicated reporting services, rather than through the functionality of the beacon itself. Thus, the beacon's primary task remains focused on marking the airport to effectively guide pilots during critical arrival phases.