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Recent developments in helicopter noise reduction

Published online by Cambridge University Press:  04 July 2016

Harry Sternfeld Jr.*
Affiliation:
The Boeing Vertol Company, Philadelphia

Extract

The helicopter industry has been experiencing a dramatic conversion from a market which was almost completely dominated by the military, to one in which the civil customer is playing an ever increasing role. As part of this change there is an increasing demand for vehicles whose interior noise levels are substantially lower than those of their predecessors.

One of the most significant recent events in the area of helicopter noise has been an impending regulatory action, rather than a technological breakthrough. This action is the development of helicopter noise standards which are currently being considered simultaneously by the International Congress of Aeronautical Organisation's (ICAO) and by the Federal Aviation Administration (FAA) in the United States. Up to the present time the specification of external noise limits, if any, were either made by individual customers, based on a particular need, or by the designer and manufacturer who might try to forecast how noisy the aircraft could be and still meet market requirements. It is highly probable that the effect of the new standards will be to require future helicopters to be substantially quieter than many of the current models.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1979 

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