Cruise noise of an advanced single-rotation propeller measured from an adjacent aircraftResults are reported from flight measurements of the noise from a full-scale SR-7L advanced single-rotation turbofan model mounted on the wing of the NASA Lewis Propfan Test Assessment (PTA) aircraft (a modified Gulfstream II). Data obtained on the PTA with an outboard microphone boom and by the NASA Lewis acoustically instrumented Learjet flying along several sidelines relative to the PTA are presented in tables and graphs and briefly discussed. It is found that the PTA-boom and Learjet sound levels are in good agreement at Mach 0.69 and altitude 20,000 ft, but the Learjet values are significantly lower than the boom levels at Mach 0.79 and altitude 36,000 ft.
Document ID
19910043642
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Woodward, Richard P. (NASA Lewis Research Center Cleveland, OH, United States)
Loeffler, Irvin J. (NASA Lewis Research Center Cleveland, OH, United States)
Ranaudo, Richard J. (NASA Lewis Research Center Cleveland, OH, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1989
Subject Category
Aircraft Propulsion And Power
Meeting Information
Meeting: International Conference on Noise Control Engineering