What is a primary function of the fuel metering unit (FMU)?

What is a primary function of the fuel metering unit (FMU)?

• A. Controls fuel consumption using signals from the FADEC
• B. Maintains hydraulic pressure
• C. Adjusts cabin temperature
• D. Regulates oil flow

Answer: (A)

Fuel metering unit translates signals from FADEC into precise fuel flow. The FADEC (Full Authority Digital Engine Control) continuously monitors engine parameters such as speed, pressure, air mass flow, and throttle demand, and determines how much fuel the engine needs. The FMU then adjusts the metering valve to deliver that exact amount of fuel to the combustor, maintaining the correct fuel pressure and fuel-air ratio across different operating conditions. This direct control of fuel delivery is what governs engine thrust and efficiency, influencing overall fuel consumption and performance. Other options describe roles handled by different systems: hydraulic pressure is managed by the hydraulic system, cabin temperature by the environmental control system, and oil flow by the lubrication system.

Fuel metering unit translates signals from FADEC into precise fuel flow. The FADEC (Full Authority Digital Engine Control) continuously monitors engine parameters such as speed, pressure, air mass flow, and throttle demand, and determines how much fuel the engine needs. The FMU then adjusts the metering valve to deliver that exact amount of fuel to the combustor, maintaining the correct fuel pressure and fuel-air ratio across different operating conditions. This direct control of fuel delivery is what governs engine thrust and efficiency, influencing overall fuel consumption and performance. Other options describe roles handled by different systems: hydraulic pressure is managed by the hydraulic system, cabin temperature by the environmental control system, and oil flow by the lubrication system.