When should the fuel shut-off valve be closed?

When should the fuel shut-off valve be closed?

• A. During preflight checks
• B. Only for emergencies or fuel system maintenance
• C. When starting the engine
• D. Never

Answer: (B)

The fuel shut-off valve controls whether fuel can flow from the tanks to the engine. In normal operation you want a continuous fuel supply, so you leave this valve open during flight and routine checks. It should be closed only to stop fuel flow in emergencies (such as a fuel leak or engine fire) or when performing maintenance on the fuel system. Closing it during preflight or engine start would interrupt fuel delivery and could cause a loss of power. After maintenance, reopen it to restore normal operation.

The fuel shut-off valve controls whether fuel can flow from the tanks to the engine. In normal operation you want a continuous fuel supply, so you leave this valve open during flight and routine checks. It should be closed only to stop fuel flow in emergencies (such as a fuel leak or engine fire) or when performing maintenance on the fuel system. Closing it during preflight or engine start would interrupt fuel delivery and could cause a loss of power. After maintenance, reopen it to restore normal operation.