Engines

N1

Definition

The rotational speed of the low-pressure compressor and fan in a turbofan engine, expressed as a percentage of maximum. N1 is the primary thrust indication on most modern turbofan engines.

Related Terms

N2

The rotational speed of the high-pressure compressor in a turbofan engine, expre...

Engine Pressure Ratio(EPR)

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

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