For what purpose is a "light gun signal" used in ATC?

• A. To synchronize flight schedules
• B. To communicate with pilots in situations of low visibility
• C. To direct ground maintenance teams
• D. To calculate fuel requirements

Answer: (B)

A light gun signal is specifically used in air traffic control to communicate with pilots in situations of low visibility. This method provides an alternative form of communication when radio contact may be impaired or unusable. The light gun emits colored signals—usually red, green, and white—that convey various instructions to pilots, such as whether to continue taxiing, take off, or land. This is particularly important in circumstances where visual flight rules cannot be adhered to, ensuring that pilots can still receive essential commands safely and effectively. The other options do not relate to the function of light gun signals in the context of air traffic control operations.