What combination causes the engine fuel shutoff valve to open?

Study for the Engines Auxiliary Power Unit Test. Prepare with multiple choice questions. Each question comes with hints and explanations. Ensure you're ready for the exam!

Multiple Choice

What combination causes the engine fuel shutoff valve to open?

Explanation:
Fuel shutoff valve opening is controlled by a manual and an electronic signal working together. When you move the start lever to IDLE, you’re indicating the engine is in the start phase and fuel delivery is being considered. The Electronic Engine Control then must actively command the valve to open to permit fuel flow. If the lever is in OFF, the valve stays closed regardless of what the EEC says. If the EEC signals to close, it won’t open the valve. A high N2 by itself isn’t enough to open the valve, since ignition/fuel flow requires both the correct lever position and an EEC authorisation. Therefore, the valve opens only when the start lever is in IDLE and the EEC signals to open.

Fuel shutoff valve opening is controlled by a manual and an electronic signal working together. When you move the start lever to IDLE, you’re indicating the engine is in the start phase and fuel delivery is being considered. The Electronic Engine Control then must actively command the valve to open to permit fuel flow. If the lever is in OFF, the valve stays closed regardless of what the EEC says. If the EEC signals to close, it won’t open the valve. A high N2 by itself isn’t enough to open the valve, since ignition/fuel flow requires both the correct lever position and an EEC authorisation. Therefore, the valve opens only when the start lever is in IDLE and the EEC signals to open.

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