FMU regulates fuel flow to which system?

FMU regulates fuel flow to which system?

• A. The Engines
• B. The Air Conditioning
• C. The Hydraulics
• D. The Electrical System

Answer: (A)

The main idea this question tests is how fuel is precisely controlled for engine thrust. The Fuel Metering Unit regulates the amount of fuel delivered to the engines, adjusting the fuel flow to match what the engine needs for the commanded thrust. It takes inputs from the thrust lever position and engine sensors (and FADEC/control logic) and uses it to meter fuel through the metering valve and fuel supply lines so the engine can maintain the desired speed and fuel-air mixture across starting, idle, climb, and cruise. This function is specific to the engines; it does not regulate fuel for other systems. Air conditioning uses bleed air (not directly metered by the FMU), hydraulics rely on engine-driven pumps for hydraulic fluid, and the electrical system uses generators for power—none of these are controlled by the FMU.

The main idea this question tests is how fuel is precisely controlled for engine thrust. The Fuel Metering Unit regulates the amount of fuel delivered to the engines, adjusting the fuel flow to match what the engine needs for the commanded thrust. It takes inputs from the thrust lever position and engine sensors (and FADEC/control logic) and uses it to meter fuel through the metering valve and fuel supply lines so the engine can maintain the desired speed and fuel-air mixture across starting, idle, climb, and cruise.

This function is specific to the engines; it does not regulate fuel for other systems. Air conditioning uses bleed air (not directly metered by the FMU), hydraulics rely on engine-driven pumps for hydraulic fluid, and the electrical system uses generators for power—none of these are controlled by the FMU.