FAA Powerplant Written Practice Test

What should be monitored to ensure efficient operation of the ignition system in turbine engines?

1. Spark plug wear

2. Electrodes condition

3. Magneto alignment

4. System voltage

The correct answer is: Spark plug wear

Monitoring spark plug wear is crucial for the efficient operation of the ignition system in turbine engines because spark plugs are responsible for initiating combustion in the combustion chamber. As spark plugs wear, their performance can degrade, leading to inconsistent spark generation, misfires, or incomplete combustion. This can affect engine efficiency, increase emissions, and potentially lead to engine damage due to unburnt fuel igniting in undesirable areas. In turbine engines, spark plugs are subjected to extreme temperatures and pressures, which can contribute to their degradation over time. Regular inspection and monitoring of spark plug condition can help ensure that they remain capable of providing a reliable spark, thereby maintaining optimal engine performance. While other options, such as the condition of electrodes, magneto alignment, and system voltage, are also important for the ignition system, they are not as directly tied to the immediate functionality and efficiency of the spark generation process in turbine engines.