What does the alternating red and green light gun signal indicate for pilots?

The alternating red and green light gun signal is specifically designed to indicate to pilots that they should exercise extreme caution. This signal is particularly important in situations where communication may be limited, such as in an emergency or when a pilot is unable to establish radio contact. The use of both colors signifies the need for heightened awareness and careful maneuvering as the aircraft may be facing potential hazards or changes in flight operations.

The alternating colors serve to alert pilots that they should be prepared for any instructions or upcoming changes, ensuring that they maintain a safe and vigilant approach. In aviation, understanding these signals is crucial for effective communication without the reliance on verbal instructions, which might not always be available.