FAA Powerplant Written Practice Test

What does the fuel control adjustment in a turbine engine primarily set?

1. Engine temperature limits

2. Idle RPM and maximum speed or EPR

3. Oil pressure thresholds

4. Fuel tank levels

The correct answer is: Idle RPM and maximum speed or EPR

The fuel control adjustment in a turbine engine primarily sets the idle RPM and maximum speed or engine pressure ratio (EPR). This is crucial for the engine's operational performance because the fuel control system regulates the amount of fuel delivered to the combustion chamber based on various inputs such as altitude, throttle position, and engine performance requirements. By adjusting the fuel control, you can ensure that the engine operates efficiently at both idle settings and during maximum power conditions. Idle RPM is vital for maintaining engine stability during low-throttle operations, while the maximum speed or EPR is essential for ensuring the engine can produce the required thrust or power when needed. Effective fuel control ensures optimal performance, safety, and efficiency of the turbine engine across its operational range. In contrast, the other options do not directly pertain to the primary responsibilities of the fuel control system. Engine temperature limits are influenced by many factors, oil pressure thresholds are part of the lubrication system, and fuel tank levels are monitored independently of the engine control functions.