FAA Powerplant Written Practice Test

What is the function of the main engine-driven fuel pump on a turbine engine?

1. To produce adequate fuel capacity at all operating conditions

2. To cool the fuel before it enters the engine

3. To recirculate excess fuel

4. To filter impurities from the fuel

The correct answer is: To produce adequate fuel capacity at all operating conditions

The main engine-driven fuel pump in a turbine engine plays a crucial role in ensuring that fuel is delivered to the engine at the appropriate pressure and flow rate required for optimal performance. Its primary function is to produce adequate fuel capacity under all operating conditions, which includes various phases like starting, idle, takeoff, and full power settings. Maintaining a consistent and sufficient supply of fuel directly impacts engine performance and efficiency. The pump must be capable of handling changes in engine demand, which can fluctuate based on throttle position and altitude. This function is vital for both the safety and efficiency of the turbine engine operation, allowing the engine to respond effectively to varying requirements during flight. While cooling the fuel, recirculating excess fuel, and filtering impurities are important aspects of the overall fuel system in a turbine engine, they are not the primary function of the main engine-driven fuel pump. Instead, these tasks are typically managed by other components within the fuel system, designed to complement and enhance the pump's function.