Preliminary Measured and Predicted XB-70 Engine Noise

Lasagna, Paul L. and McLeod, Norman J. (1968) Preliminary Measured and Predicted XB-70 Engine Noise. Technical Report NASA TM X-1565, Research Engineering, NASA Dryden Flight Research Center.

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Abstract

Noise measurements on the ground were made during takeoffs, a landing, and a flyby of the XB-70 airplane. Noise predictions made by using the SAE method differed from the measured levels. The substitution of standard-day atmosphere for actual atmosphere improved the comparison of the measured and predicted noise spectra. Further investigation is needed to determine the reasons for the differences between the measured and the predicted levels. Perceived noise levels of the XB-70 were approximately 7 PNdB to 10 PNdB higher than the maximum overall sound-pressure levels in decibels.

EPrint Type:	NASA Technical Memorandum
Keywords:	Acoustic measurement, Data reduction, Engine noise, J-93 engine, XB-70 aircraft
Subjects:	(01 - 09) Aeronautics: (05) Aircraft Design, Testing And Performance Aircraft/Project: XB-70
ID Code:	828
Deposited On:	27 March 2006
Additional Information:	21 pages.