Prediction and Modeling of Helicopter Noise.

Abstract

Sound exposure level (SEL) data from three Army helicopters were used to test a proposed method for calculating sideline decay developed for fixed-wing aircraft. The Federal Aviation Administration (FAA) and the U.S. Air Force (USAF) have adopted this method for use with fixed-wing aircraft, and it was desired to know if the same method could predict rotary-wing aircraft sideline decay with distance or if a more complex computer model is necessary. The procedure was found accurate for limited altitudes and slant distances. In addition, the sideline decay data were studied using variables known to affect sound attenuation. The purpose was to gain further insight into the mechanisms of sideline decay with distance. Variations in the results suggest an unknown mechanism is contributing to this attenuation. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1984
Accession Number
ADA145764

Entities

People

  • M. Kief
  • Richard Raspet
  • Robert A. Daniels

Organizations

  • Construction Engineering Research Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Biomedical

DTIC Thesaurus Topics

  • Acoustic Propagation
  • Acoustics
  • Air Force
  • Aircraft Equipment
  • Aircraft Noise
  • Aircrafts
  • Airframes
  • Altitude
  • Atmospheric Attenuation
  • Engineering
  • Environment
  • Fixed Wing Aircraft
  • Frequency Bands
  • Geography
  • Helicopters
  • Libraries
  • Rotary Wing Aircraft

Fields of Study

  • Physics

Readers

  • Acoustics.
  • Aerospace logistics and air mobility.
  • Systems Analysis and Design