Airborne Transportation Noise—Its Origin and Abatement

The growth of airborne transportation has resulted in an increased awareness of the sounds associated with this form of travel. The noise generated by propeller‐driven aircraft is given way to the sound of the exhaust jet, the compressor, and the fan whine. In addition, with the advent of supersonic flight, a new sound, the sonic boom, has been introduced to our acoustic environment. It is anticipated that airborne transportation will increase markedly in the coming years and as a result there could be a marked increase in the noise problem. The Federal Aviation Administration is attempting to minimize the acoustic impact of this increased air travel by attacking the problem on many fronts. The problem is initially defined through the mechanism of noise exposure forecasting. Methods are continually sought to reduce the noise at the source, to alter the sound transmission path, and to protect the community from the acoustic intrusion. Finally, procedures for national and international certification and regulation are being explored as a means of noise control.