When are the fuel Shut Off Valves (SOVs) closed?

When are the fuel Shut Off Valves (SOVs) closed?

• A. During startup
• B. At shutdown
• C. When pressure is high
• D. After maintenance

Answer: (B)

Fuel shut-off valves are used to stop fuel flow and isolate the fuel system when the engine is not running. They are closed at shutdown so the fuel supply is cut off and residual fuel can’t leak or spray, reducing fire risk and making the system safe for post-shutdown checks and maintenance. For starting, these valves must be opened to allow fuel to reach the combustors; during normal operation they stay open. They aren’t closed because pressure is high—the system uses pumps and regulators to manage pressure, not the shutdown valves. After maintenance, isolating the fuel system may be required, but the routine rule is to close them at shutdown.

Fuel shut-off valves are used to stop fuel flow and isolate the fuel system when the engine is not running. They are closed at shutdown so the fuel supply is cut off and residual fuel can’t leak or spray, reducing fire risk and making the system safe for post-shutdown checks and maintenance. For starting, these valves must be opened to allow fuel to reach the combustors; during normal operation they stay open. They aren’t closed because pressure is high—the system uses pumps and regulators to manage pressure, not the shutdown valves. After maintenance, isolating the fuel system may be required, but the routine rule is to close them at shutdown.