What does selection of the AFT CARGO SMOKE switch light do?

• A. Arms both bottles to the aft cargo bay, closes both the intake and exhaust shutoff valves, and turns off the auxiliary heater
• B. Arms only one bottle
• C. Disables all smoke detectors
• D. Energizes the cargo fans

Answer: (A)

The switch light tests your knowledge of how the aft cargo fire suppression system is prepared. When you select the AFT CARGO SMOKE switch, it arms both extinguishing bottles for the aft cargo bay, closes the intake and exhaust shutoff valves to isolate the bay from the aircraft’s ventilation, and turns off the auxiliary heater. This combination prepares the system to suppress a fire in the aft cargo area and prevents smoke or hot air from circulating through the cabin or other compartments. It’s not about disabling detectors, nor about energizing the cargo fans, and it ensures both bottles are ready rather than just one. The light simply shows the system is armed, with discharge typically occurring automatically on fire detection or via manual action.