Commercial Pilot License (CPL) 2026 – 400 Free Practice Questions to Pass the Exam

Preignition in an aircraft engine refers to the phenomenon where fuel ignites before the normal ignition event occurs, which is typically triggered by the spark plug in the case of spark-ignited engines. This premature ignition can lead to several issues, including increased engine temperatures, potential knocking or pinging, and, in severe cases, engine damage. Understanding preignition is crucial for pilots and maintenance personnel, as it can disrupt engine performance and reliability.

The other options describe different scenarios. While option A discusses the ideal scenario of fuel igniting at the correct timing, it does not encapsulate the essence of preignition. Option C relates to inadequate airflow, which can impact engine performance but is not connected to the timing of fuel ignition. Option D addresses complete engine shutdown, which is a critical issue but fundamentally different from the concept of preignition.