Which type of valve is closed to stop fuel flow in case of fire?

• A. Electrically Operated Shut-Off Valves
• B. Manually Operated Shut-Off Valves
• C. Check Valves
• D. Selector Valve

Answer: (B)

The correct choice is the manually operated shut-off valve. This type of valve is specifically designed to be closed quickly and intentionally by personnel to stop fuel flow in the event of an emergency, such as a fire. The manual operation feature provides an immediate response capability, allowing crew members to take control and mitigate hazards without relying on electrical systems, which may be compromised in a fire situation.

Manually operated shut-off valves are typically located in accessible positions to ensure rapid action can be taken when needed. These valves are critical for safety in aviation environments, enabling crew members to act swiftly to prevent the spread of fire by cutting off the fuel supply.

In contrast, electrically operated shut-off valves, while also effective, depend on electrical systems and may not be the best choice in emergency situations if those systems are damaged. Check valves serve a different function, ensuring fluid flows in one direction and preventing backflow rather than shutting off flow completely. Selector valves are used to direct flow to different systems or components but do not function primarily as safety shut-offs in emergencies.