At what fuel pressure level does the red FUEL PX annunciator activate?

• A. 5 psi
• B. 10 psi
• C. 15 psi
• D. 20 psi

Answer: (B)

The red FUEL PX annunciator activates at a fuel pressure level of 10 psi. This alarm is crucial for ensuring that the fuel system is functioning properly. Fuel pressure is essential for maintaining engine performance; when it drops to 10 psi, it is indicative of potential issues within the fuel system, such as low fuel supply or a malfunctioning pump.

The activation of this warning light serves as an alert to the crew, prompting immediate attention to the fuel system to avoid potential engine failure or performance degradation. Understanding this pressure threshold is essential for pilots and maintenance personnel to take prompt and appropriate action to maintain safety and operational integrity.