When the landing gears are up and the throttles are retarded, the warning horn will not sound if an open occurs in wire ________.

When the landing gears are up and the throttles are retarded, the warning horn will not sound if an open occurs in wire ________.

• A. No. 3
• B. No. 4
• C. No. 5
• D. No. 6

Answer: (C)

A warning horn only sounds when there is a complete electrical path from the power source through the interlocks to the horn. In this gear-up, throttles-retarded condition, the horn’s circuit is closed only if each segment in the path is intact, with wire No.5 serving as the final link in that path. If wire No.5 is open, the circuit is broken and no current reaches the horn, so it will not sound. That’s why the correct choice is the one corresponding to wire No.5.

A warning horn only sounds when there is a complete electrical path from the power source through the interlocks to the horn. In this gear-up, throttles-retarded condition, the horn’s circuit is closed only if each segment in the path is intact, with wire No.5 serving as the final link in that path. If wire No.5 is open, the circuit is broken and no current reaches the horn, so it will not sound. That’s why the correct choice is the one corresponding to wire No.5.