How Do Jet Engine Startup Procedures Work?

Simple Flying

A series of steps must be followed for an engine start up process.

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Jet engines consist of intake, compressor stage, combustor, and turbine stage. Air is compressed, fuel is introduced, and expansion creates thrust.
N2 compressor must be rotated to start the engine. This can be achieved using electricity or an air starter motor.
Startup malfunctions include hot starts (insufficient airflow) and hung starts (low RPM). A blowout cycle is necessary if a start fails to clear excess fuel. In-flight restarts rely on windmilling or assistance from other engines or APU.