Engines

N2

Definition

The rotational speed of the high-pressure compressor in a turbofan engine, expressed as a percentage. N2 indicates core engine speed and is used to monitor engine health and starting.

Related Terms

N1

The rotational speed of the low-pressure compressor and fan in a turbofan engine...

Engine Pressure Ratio(EPR)

The ratio of turbine discharge pressure to compressor inlet pressure, used as a ...

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