FAA Powerplant Written Practice Test

What occurs to the igniter during turbine operation to prevent fouling?

1. Constant cleaning by airflow

2. High intensity ignition spark

3. Automatic temperature regulation

4. Periodic replacement

The correct answer is: High intensity ignition spark

During turbine operation, the igniter generates a high-intensity ignition spark. This strong spark is crucial because it helps ensure a reliable ignition of the fuel-air mixture in the combustion chamber. The intensity of the spark is necessary to ignite the fuel efficiently and prevent issues related to incomplete combustion, such as fouling. Moreover, the high-intensity spark plays a role in minimizing the build-up of carbon deposits and contaminants on the igniter surface, which can occur if the ignition process is weak or ineffective. If the igniter were to use a lower intensity spark, it could lead to sporadic ignition events, leading to increased fouling over time. Thus, this design ensures that the igniter remains effective throughout the operational cycle of the turbine, ultimately contributing to smoother, more efficient engine performance. While other options such as cleaning by airflow, temperature regulation, and periodic replacement are considerations in the maintenance and operation of turbine engines, the primary mechanism preventing fouling of the igniter itself during operation is the generation of a high-intensity ignition spark.