The control valve switch must be placed in the neutral position when the landing gears are down to ________.

The control valve switch must be placed in the neutral position when the landing gears are down to ________.

• A. Delay the horn
• B. Immediately sound the horn
• C. Prevent the warning horn from sounding when the throttles are closed
• D. No effect

Answer: (C)

When the landing gear are down, the warning horn system is designed to stay quiet unless there’s a true fault. Placing the control valve switch in the neutral position isolates the throttle-position input from the horn circuit, so closing the throttles won’t trigger the horn. This keeps the cockpit from hearing a nuisance warning during approach or after landing when gear are down. Therefore, the correct outcome is to prevent the warning horn from sounding when the throttles are closed. The other options would either imply delaying or triggering the horn, or having no effect, which doesn’t align with how the interlock is intended to work.

When the landing gear are down, the warning horn system is designed to stay quiet unless there’s a true fault. Placing the control valve switch in the neutral position isolates the throttle-position input from the horn circuit, so closing the throttles won’t trigger the horn. This keeps the cockpit from hearing a nuisance warning during approach or after landing when gear are down. Therefore, the correct outcome is to prevent the warning horn from sounding when the throttles are closed. The other options would either imply delaying or triggering the horn, or having no effect, which doesn’t align with how the interlock is intended to work.