What is the purpose of igniter plugs in an engine?

The purpose of igniter plugs in an engine is to ignite the fuel during engine start. Igniter plugs create a spark when electricity is applied, which is essential for initiating the combustion process in a gas turbine or jet engine. This ignition is crucial for starting the engine, as without it, the fuel would not ignite, and the engine would fail to begin operation.

The other functions listed do not accurately describe the role of igniter plugs. Routing fuel, cooling the combustion chamber, and balancing the rotor assembly pertain to different components and systems within the engine that serve other specific purposes. Understanding the exact role of igniter plugs helps to clarify their importance in the operation of an engine during the start-up phase.