NASA Technologies Significantly Reduce Aircraft Noise
A series of NASA flight tests has successfully demonstrated technologies that achieve a significant reduction in the noise generated by aircraft and heard by communities near airports.
The Acoustic Research Measurement (ARM) flights, which concluded in May, at NASA’s Armstrong Flight Research Center in California, tested technology to address airframe noise, or noise that is produced by non-propulsive parts of the aircraft, during landing.
The flights successfully combined several technologies to achieve a greater than 70 percent reduction in airframe noise.
NASA
https://www.nasa.gov/press-release/nasa-technologies-significantly-reduce-aircraft-noise
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