What does the activation of a Rotating Beacon indicate?

The activation of a rotating beacon is used primarily to indicate that the visibility is limited, which is often associated with Instrument Flight Rules (IFR) conditions. These beacons are designed to provide pilots with a visual reference to identify an airport even when visibility is poor due to weather factors such as fog, rain, or low clouds, which typically necessitate IFR procedures.

The illumination of rotating beacons serves as an important navigational aid, signaling that pilots should be prepared for potential instrument flight conditions as they approach the airport. By contrast, when visibility is good and weather conditions are favorable for visual navigation, a rotating beacon would typically not be activated, aligning with Visual Flight Rules (VFR) conditions. This understanding is crucial for pilots to safely determine their flight operations based on prevailing weather conditions.