Which action does the external overspeed/overtemp assembly perform when thresholds are exceeded?

Which action does the external overspeed/overtemp assembly perform when thresholds are exceeded?

• A. Auto-restart the engine.
• B. Initiates engine shutdown.
• C. Opens the fuel control valve.
• D. Triggers a cabin alert.

Answer: (B)

When rpm or temperature exceed safe limits, the external overspeed/overtemp assembly acts as a protective interlock that forces the engine to shut down. Its primary purpose is to prevent damage by stopping operation, typically by cutting fuel flow or otherwise commanding shutdown, so the engine doesn’t continue running under unsafe conditions. Auto-restart would defeat this protection and can lead to severe damage, while opening the fuel control valve would add fuel and worsen the condition. Triggering a cabin alert might occur, but it’s not the main action of this assembly; its essential function is to initiate engine shutdown to protect the system.

When rpm or temperature exceed safe limits, the external overspeed/overtemp assembly acts as a protective interlock that forces the engine to shut down. Its primary purpose is to prevent damage by stopping operation, typically by cutting fuel flow or otherwise commanding shutdown, so the engine doesn’t continue running under unsafe conditions. Auto-restart would defeat this protection and can lead to severe damage, while opening the fuel control valve would add fuel and worsen the condition. Triggering a cabin alert might occur, but it’s not the main action of this assembly; its essential function is to initiate engine shutdown to protect the system.