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NASA Glenn's Contributions to Aircraft Engine Noise Research

AbstractThis paper reviews all engine noise research conducted at the National Aeronautics and Space Administration (NASA) Glenn Research Center over the last 70 years. The review includes a historical perspective of the center and the facilities used to conduct the research. Major NASA noise research programs are highlighted, showing their impact on the industry and on the development of aircraft noise reduction technology. Noise reduction trends are discussed, and future aircraft concepts are presented. Results show that, since the 1960s, the average perceived noise level has been reduced by about 20 dB. Studies show that, depending on the size of the airport, the aircraft fleet mix, and the actual growth in air travel, another 15–17 dB is required to achieve NASA’s long-term goal of providing technologies to limit objectionable noise to the boundaries of an average airport.