What does a flashing red light signal from a control tower indicate?

A flashing red light signal from a control tower is a critical alert for pilots. The primary meaning of this signal is that it indicates it is unsafe to land. This can occur for various reasons, such as issues on the runway or other unsafe conditions that could compromise the safety of an incoming aircraft. Recognizing and responding appropriately to this signal is essential for maintaining safety during flight operations.

In contrast, other signals serve different purposes. For example, a steady red light, while not part of the question, typically indicates to pilots to hold their current position, reinforcing the importance of understanding various signals. Being familiar with these signals is part of situational awareness and critical decision-making skills that every pilot should master during their training.