N1

N1 (plural N1s)

1. (aviation) The rotational speed of the low-pressure spool of a multiple-spool gas turbine engine, expressed as a percentage of a certain reference rotational speed.
   • 2004 October 26, National Transportation Safety Board, “1.16.2.2 Flight 587 Simulation”, in Aircraft Accident Report: In-Flight Separation of Vertical Stabilizer, American Airlines Flight 587, Airbus Industrie A300-605R, N14053, Belle Harbor, New York, November 12, 2001‎, archived from the original on 3 July 2022, page 56:

     The load factor and engine N1 data fluctuations recorded on the FDR suggested that flight 587 encountered the wake of Japan Air Lines flight 47 for the second time between about 0915:50 and 0915:54 and that the motion of the airplane was affected by the wake vortex during this time.

• N2
• N3